AI Trajectory

Trajectory: (Expand/Collapse All)
Seq	Timestamp	Type	Name	Duration
0/0	2026/10/08 05:20	flow	patch-triage	5m Args: null Results: { "EnableConfigs": [ "ISCSI_TCP", "SCSI", "INET" ], "FocusSymbols": [ "iscsi_tcp_zero_unread", "iscsi_tcp_complete_cmd", "iscsi_tcp_data_recv_done", "iscsi_tcp_data_in", "iscsi_tcp_process_data_in", "iscsi_tcp_hdr_dissect", "iscsi_tcp_task_init", "iscsi_tcp_recv_skb" ], "KMSANReasoning": "The patch introduces logic in the iSCSI TCP transport layer to track the amount of received Data-In bytes (`data_in_bytes`) and zero out the unread remainder of the SCSI command's scatterlist buffer via `sg_zero_buffer()` upon command completion.\n\n1. Uninitialized Memory / KMSAN applicability:\n- The only newly introduced variable is `data_in_bytes` in `struct iscsi_tcp_task`, which is explicitly initialized to 0 in `iscsi_tcp_task_init()`.\n- The patch zeroes out buffer memory (`sg_zero_buffer`) rather than creating uninitialized gaps or leaking uninitialized memory.\n- No uninitialized struct fields, stack allocations, or kernel structures exposed to userspace are introduced or read.\n\n2. KASAN / LOCKDEP applicability:\n- Any risks associated with buffer offsets, lengths passed to `sg_zero_buffer()`, or scatterlist traversal bounds are out-of-bounds access risks, which are directly detected by standard KASAN.\n- Concurrency and lock acquisitions around `session-\u003eback_lock` in `iscsi_tcp_complete_cmd()` are monitored by LOCKDEP.\n- Command task lifecycle and pointer validity (`task`, `task-\u003esc`) are caught by KASAN / standard kernel checks.\n\nBecause the changes do not introduce or expose uninitialized memory risks, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false, "Reasoning": "The patch introduces buffer zeroing and continuity checks in the software iSCSI over TCP stack (libiscsi_tcp). It adds iscsi_tcp_zero_unread() and iscsi_tcp_complete_cmd() to zero unread tails of read buffers using sg_zero_buffer(), tracks received data bytes to ensure continuity, and restructures command completion across PDU dissection and processing routines. iSCSI over TCP is a software transport protocol completely reachable in virtualized environments via standard TCP sockets and NETLINK_ISCSI.", "WorthFuzzing": true }
1/1	2026/10/08 05:20	action	read-patch-diff	0m Args: null Results: { "PatchDiff": "commit ebe36cf47a49aab5d488d55e8618e60c7fb9b291\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Thu Oct 8 05:20:42 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c\nindex d35f93451ee9b..00bdbcc6e27e3 100644\n--- a/drivers/scsi/libiscsi_tcp.c\n+++ b/drivers/scsi/libiscsi_tcp.c\n@@ -397,6 +397,61 @@ void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn tcp_conn)\n }\n EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep);\n \n+/\n+ iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent\n+ * @task: scsi command task\n+ \n+ A target can end a read without sending all of the data, in any of the ways\n+ * a completion can be reported. Rather than predict from the status, the\n+ * sense and the residual whether the buffer was promised in full, zero the\n+ * bytes that did not arrive. Whatever the midlayer then reports as\n+ * transferred, the caller sees zeroes and not the previous contents of those\n+ * pages.\n+ \n+ The continuity check in iscsi_tcp_data_in() means the bytes that did not\n+ * arrive are exactly the tail, so one range covers them.\n+ /\n+static void iscsi_tcp_zero_unread(struct iscsi_task task)\n+{\n+\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\n+\tstruct scsi_cmnd sc = task-\u003esc;\n+\n+\tif (!sc \|\| sc-\u003esc_data_direction != DMA_FROM_DEVICE \|\|\n+\t tcp_task-\u003edata_in_bytes \u003e= sc-\u003esdb.length)\n+\t\treturn;\n+\n+\tsg_zero_buffer(sc-\u003esdb.table.sgl, sc-\u003esdb.table.nents,\n+\t\t sc-\u003esdb.length - tcp_task-\u003edata_in_bytes,\n+\t\t tcp_task-\u003edata_in_bytes);\n+}\n+\n+/*\n+ iscsi_tcp_complete_cmd - zero any unread tail, then complete the command\n+ * @conn: iscsi connection\n+ * @hdr: the PDU carrying the status\n+ * @data: data segment of that PDU, if it has one\n+ * @datalen: length of @data\n+ \n+ back_lock is taken once for the lookup, the fill and the completion.\n+ /\n+static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr,\n+\t\t\t\t char data, int datalen)\n+{\n+\tstruct iscsi_task task;\n+\tint rc;\n+\n+\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\n+\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\n+\tif (!task) {\n+\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n+\t\treturn ISCSI_ERR_BAD_ITT;\n+\t}\n+\tiscsi_tcp_zero_unread(task);\n+\trc = __iscsi_complete_pdu(conn, hdr, data, datalen);\n+\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n+\treturn rc;\n+}\n+\n /\n * Handle incoming reply to any other type of command\n /\n@@ -410,8 +465,13 @@ iscsi_tcp_data_recv_done(struct iscsi_tcp_conn tcp_conn,\n \tif (!iscsi_tcp_dgst_verify(tcp_conn, segment))\n \t\treturn ISCSI_ERR_DATA_DGST;\n \n-\trc = iscsi_complete_pdu(conn, tcp_conn-\u003ein.hdr,\n-\t\t\tconn-\u003edata, tcp_conn-\u003ein.datalen);\n+\tif ((tcp_conn-\u003ein.hdr-\u003eopcode \u0026 ISCSI_OPCODE_MASK) ==\n+\t ISCSI_OP_SCSI_CMD_RSP)\n+\t\trc = iscsi_tcp_complete_cmd(conn, tcp_conn-\u003ein.hdr, conn-\u003edata,\n+\t\t\t\t\t tcp_conn-\u003ein.datalen);\n+\telse\n+\t\trc = iscsi_complete_pdu(conn, tcp_conn-\u003ein.hdr, conn-\u003edata,\n+\t\t\t\t\ttcp_conn-\u003ein.datalen);\n \tif (rc)\n \t\treturn rc;\n \n@@ -509,6 +569,11 @@ static int iscsi_tcp_data_in(struct iscsi_conn conn, struct iscsi_task task)\n \t\treturn ISCSI_ERR_DATA_OFFSET;\n \t}\n \n+\tif (tcp_task-\u003edata_offset != tcp_task-\u003edata_in_bytes)\n+\t\treturn ISCSI_ERR_DATA_OFFSET;\n+\n+\ttcp_task-\u003edata_in_bytes += tcp_conn-\u003ein.datalen;\n+\n \tconn-\u003edatain_pdus_cnt++;\n \treturn 0;\n }\n@@ -658,7 +723,7 @@ iscsi_tcp_process_data_in(struct iscsi_tcp_conn tcp_conn,\n \n \t/ check for non-exceptional status /\n \tif (hdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS) {\n-\t\trc = iscsi_complete_pdu(conn, tcp_conn-\u003ein.hdr, NULL, 0);\n+\t\trc = iscsi_tcp_complete_cmd(conn, tcp_conn-\u003ein.hdr, NULL, 0);\n \t\tif (rc)\n \t\t\treturn rc;\n \t}\n@@ -752,6 +817,14 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n \t\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n \t\t\treturn rc;\n \t\t}\n+\t\t/\n+\t\t * A Data-In with no data segment can still carry the status,\n+\t\t * and it completes the command here rather than from\n+\t\t * iscsi_tcp_process_data_in(), so fill the tail on this path\n+\t\t * too.\n+\t\t /\n+\t\tif (hdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS)\n+\t\t\tiscsi_tcp_zero_unread(task);\n \t\trc = __iscsi_complete_pdu(conn, hdr, NULL, 0);\n \t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n \t\tbreak;\n@@ -783,6 +856,11 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n \t\t\tbreak;\n \t\t}\n \n+\t\tif (opcode == ISCSI_OP_SCSI_CMD_RSP \u0026\u0026 !tcp_conn-\u003ein.datalen) {\n+\t\t\trc = iscsi_tcp_complete_cmd(conn, hdr, NULL, 0);\n+\t\t\tbreak;\n+\t\t}\n+\n \t\t/ If there's data coming in with the response,\n \t\t * receive it to the connection's buffer.\n \t\t /\n@@ -995,6 +1073,7 @@ int iscsi_tcp_task_init(struct iscsi_task task)\n \n \tBUG_ON(kfifo_len(\u0026tcp_task-\u003er2tqueue));\n \ttcp_task-\u003eexp_datasn = 0;\n+\ttcp_task-\u003edata_in_bytes = 0;\n \n \t/* Prepare PDU, optionally w/ immediate data /\n \tISCSI_DBG_TCP(conn, \"task deq [itt 0x%x imm %d unsol %d]\\n\",\ndiff --git a/include/scsi/libiscsi_tcp.h b/include/scsi/libiscsi_tcp.h\nindex ef53d4bea28a0..a6e63db75d674 100644\n--- a/include/scsi/libiscsi_tcp.h\n+++ b/include/scsi/libiscsi_tcp.h\n@@ -66,6 +66,7 @@ struct iscsi_tcp_conn {\n \n struct iscsi_tcp_task {\n \tuint32_t\t\texp_datasn;\t/ expected target's R2TSN/DataSN /\n+\tuint32_t\t\tdata_in_bytes;\t/ Data-In payload received /\n \tint\t\t\tdata_offset;\n \tstruct iscsi_r2t_info\tr2t;\t\t/* in progress solict R2T */\n \tstruct iscsi_pool\tr2tpool;\n" }
2/1	2026/10/08 05:20	agent	patch-evaluator	2m Model: core Args: null Results: { "EnableConfigs": [ "ISCSI_TCP", "SCSI", "INET" ], "FocusSymbols": [ "iscsi_tcp_zero_unread", "iscsi_tcp_complete_cmd", "iscsi_tcp_data_recv_done", "iscsi_tcp_data_in", "iscsi_tcp_process_data_in", "iscsi_tcp_hdr_dissect", "iscsi_tcp_task_init", "iscsi_tcp_recv_skb" ], "Reasoning": "The patch introduces buffer zeroing and continuity checks in the software iSCSI over TCP stack (libiscsi_tcp). It adds iscsi_tcp_zero_unread() and iscsi_tcp_complete_cmd() to zero unread tails of read buffers using sg_zero_buffer(), tracks received data bytes to ensure continuity, and restructures command completion across PDU dissection and processing routines. iSCSI over TCP is a software transport protocol completely reachable in virtualized environments via standard TCP sockets and NETLINK_ISCSI.", "WorthFuzzing": true } Instruction: You are an expert Linux kernel maintainer and security engineer. Your job is to review a provided patch series and evaluate whether it warrants fuzzing with syzkaller. IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in your workspace. Do NOT rely on internal assumptions. You must actively use your code access tools to inspect the actual source code, callers, and surrounding context. ================================================================================ 1. CORE TRIAGE PHILOSOPHY ================================================================================ The goal of patch fuzzing is to discover crashes, regressions, exposed latent bugs, and newly triggered assertions introduced by the patch series. - REACHABILITY IS THE PRIMARY GATE: Fuzzing can only discover bugs in code that can actually execute in standard virtualized environments (GCE or QEMU, utilizing software-emulated devices like USB gadgets, netdev, tun/tap). If the modified code is structurally unreachable (see Section 2), it MUST NOT be fuzzed, regardless of whether it adds assertions or complex logic. - DO NOT BLINDLY TRUST "NO FUNCTIONAL CHANGE" (NFCI) OR "REFACTORING" CLAIMS: Patch authors routinely label changes as "cleanups", "refactorings", or state "No functional change intended". Do NOT take these claims at face value. Code refactorings that rearrange logic, introduce helper functions, or alter state management in core subsystems frequently introduce subtle semantic shifts or uncover latent kernel bugs. If reachable executable code is modified or refactored, it MUST be fuzzed. - NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED: When a patch introduces or modifies runtime checks or assertions (e.g., WARN_ON, VM_WARN_ON, BUG_ON, lockdep_assert) in reachable code paths, it enforces new or stricter invariants. Even if the author believes the invariant always holds, fuzzing is essential to verify whether an unusual sequence of operations can violate it. ================================================================================ 2. WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA) ================================================================================ Return WorthFuzzing=false ONLY IF all modified code falls strictly into one or more of these categories: - Non-kernel and non-executable changes: * Modifications to Documentation/, comments, or spelling fixes. * User-space directories, self-tests, samples, or scripts (e.g., tools/, samples/, scripts/, usr/) that do not affect the compiled kernel image (vmlinux) or kernel modules. * Purely decorative logging (e.g., message strings in pr_err, printk, dev_info) or tracepoints that do not alter control flow or data structures. * Build system or Kconfig changes that do not alter compiled C logic. - Structurally unreachable hardware: * Vendor-specific PCIe switches, SmartNICs, or GPU drivers (e.g., mlxsw, pds_core, qed, ionic, amdgpu) requiring physical ASIC/PCIe cards not emulated in standard QEMU. - Unreachable execution paths: * Driver teardown callbacks (.remove, .shutdown, pci_unregister_driver) executed only during physical PCI hot-unplug or manual sysfs driver unbinding. * Code paths exclusive to architectures other than the target architecture. ================================================================================ 3. WHEN TO RETURN WorthFuzzing=true (POSITIVE CRITERIA) ================================================================================ Return WorthFuzzing=true whenever the patch touches reachable executable code, including: - Core Subsystems: * Any logic modifications in memory management (mm/), synchronization/locking (kernel/locking/), BPF, scheduler, core networking, VFS, or syscall handling. - Refactorings and Code Cleanups: * Any restructuring of reachable data structures, helper abstractions, or algorithm flows. - Runtime Assertions and Defensive Checks: * Any introduction or alteration of assertions (WARN_ON, VM_WARN_ON, BUG_ON, etc.) in reachable paths. - Reachable Drivers and Protocols: Drivers accessible via virtual buses (virtio, USB gadget, loopback, netlink, binder, sockets, etc.). ================================================================================ 4. EXTRACTING FocusSymbols (PREVENTING DILUTION) ================================================================================ When WorthFuzzing=true, you must extract specific kernel functions into FocusSymbols to guide the fuzzer: - AVOID UBIQUITOUS LIFECYCLE HOT-PATHS: Do NOT list generic, ubiquitous functions called by almost every program in the corpus (including, but not limited to: general memory allocators and deallocators, page fault and trap handlers, or core synchronization primitives; this is not an exhaustive list). Listing ubiquitous functions causes the fuzzer to classify thousands of unrelated tests as "focused", which severely dilutes fuzzing effort away from the actual changes. - TARGET SPECIFIC FEATURE LOGIC AND ENTRYPOINTS: List functions that specifically implement the logic being added or altered, or direct API entrypoints for the subsystem feature under review. - HANDLING STATIC INLINE FUNCTIONS IN HEADERS (.h): Compiler-inlined static functions (such as static inlines in mm/.h or include/linux/.h) lack distinct symbol addresses in vmlinux and cannot be targeted directly by symbol coverage filters. If the changes are primarily in static inline helpers, identify non-static, feature-specific caller functions in .c files that exercise them (avoiding ubiquitous lifecycle wrappers). ================================================================================ 5. IDENTIFYING EnableConfigs ================================================================================ Identify any specific CONFIG_ options required to properly compile and reach the modified code: - Inspect Kconfig files and #ifdef guards; do not make assumptions. - Check "depends on" lines in Kconfig to include any non-standard parent subsystem configs needed. - Strip any 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4"). Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit ebe36cf47a49aab5d488d55e8618e60c7fb9b291 Author: syz-cluster <triage@syzkaller.com> Date: Thu Oct 8 05:20:42 2026 +0000 syz-cluster: applied patch under review diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c index d35f93451ee9b..00bdbcc6e27e3 100644 --- a/drivers/scsi/libiscsi_tcp.c +++ b/drivers/scsi/libiscsi_tcp.c @@ -397,6 +397,61 @@ void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn tcp_conn) } EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep); +/* + * iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent + * @task: scsi command task + * + * A target can end a read without sending all of the data, in any of the ways + * a completion can be reported. Rather than predict from the status, the + * sense and the residual whether the buffer was promised in full, zero the + * bytes that did not arrive. Whatever the midlayer then reports as + * transferred, the caller sees zeroes and not the previous contents of those + * pages. + * + * The continuity check in iscsi_tcp_data_in() means the bytes that did not + * arrive are exactly the tail, so one range covers them. + / +static void iscsi_tcp_zero_unread(struct iscsi_task task) +{ + struct iscsi_tcp_task tcp_task = task->dd_data; + struct scsi_cmnd sc = task->sc; + + if (!sc \|\| sc->sc_data_direction != DMA_FROM_DEVICE \|\| + tcp_task->data_in_bytes >= sc->sdb.length) + return; + + sg_zero_buffer(sc->sdb.table.sgl, sc->sdb.table.nents, + sc->sdb.length - tcp_task->data_in_bytes, + tcp_task->data_in_bytes); +} + +/** + * iscsi_tcp_complete_cmd - zero any unread tail, then complete the command + * @conn: iscsi connection + * @hdr: the PDU carrying the status + * @data: data segment of that PDU, if it has one + * @datalen: length of @data + * + * back_lock is taken once for the lookup, the fill and the completion. + / +static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr, + char data, int datalen) +{ + struct iscsi_task task; + int rc; + + spin_lock(&conn->session->back_lock); + task = iscsi_itt_to_ctask(conn, hdr->itt); + if (!task) { + spin_unlock(&conn->session->back_lock); + return ISCSI_ERR_BAD_ITT; + } + iscsi_tcp_zero_unread(task); + rc = __iscsi_complete_pdu(conn, hdr, data, datalen); + spin_unlock(&conn->session->back_lock); + return rc; +} + / * Handle incoming reply to any other type of command / @@ -410,8 +465,13 @@ iscsi_tcp_data_recv_done(struct iscsi_tcp_conn tcp_conn, if (!iscsi_tcp_dgst_verify(tcp_conn, segment)) return ISCSI_ERR_DATA_DGST; - rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, - conn->data, tcp_conn->in.datalen); + if ((tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK) == + ISCSI_OP_SCSI_CMD_RSP) + rc = iscsi_tcp_complete_cmd(conn, tcp_conn->in.hdr, conn->data, + tcp_conn->in.datalen); + else + rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, conn->data, + tcp_conn->in.datalen); if (rc) return rc; @@ -509,6 +569,11 @@ static int iscsi_tcp_data_in(struct iscsi_conn conn, struct iscsi_task task) return ISCSI_ERR_DATA_OFFSET; } + if (tcp_task->data_offset != tcp_task->data_in_bytes) + return ISCSI_ERR_DATA_OFFSET; + + tcp_task->data_in_bytes += tcp_conn->in.datalen; + conn->datain_pdus_cnt++; return 0; } @@ -658,7 +723,7 @@ iscsi_tcp_process_data_in(struct iscsi_tcp_conn tcp_conn, / check for non-exceptional status / if (hdr->flags & ISCSI_FLAG_DATA_STATUS) { - rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0); + rc = iscsi_tcp_complete_cmd(conn, tcp_conn->in.hdr, NULL, 0); if (rc) return rc; } @@ -752,6 +817,14 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr) spin_unlock(&conn->session->back_lock); return rc; } + / + * A Data-In with no data segment can still carry the status, + * and it completes the command here rather than from + * iscsi_tcp_process_data_in(), so fill the tail on this path + * too. + / + if (hdr->flags & ISCSI_FLAG_DATA_STATUS) + iscsi_tcp_zero_unread(task); rc = __iscsi_complete_pdu(conn, hdr, NULL, 0); spin_unlock(&conn->session->back_lock); break; @@ -783,6 +856,11 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr) break; } + if (opcode == ISCSI_OP_SCSI_CMD_RSP && !tcp_conn->in.datalen) { + rc = iscsi_tcp_complete_cmd(conn, hdr, NULL, 0); + break; + } + / If there's data coming in with the response, * receive it to the connection's buffer. / @@ -995,6 +1073,7 @@ int iscsi_tcp_task_init(struct iscsi_task task) BUG_ON(kfifo_len(&tcp_task->r2tqueue)); tcp_task->exp_datasn = 0; + tcp_task->data_in_bytes = 0; /* Prepare PDU, optionally w/ immediate data / ISCSI_DBG_TCP(conn, "task deq [itt 0x%x imm %d unsol %d]\n", diff --git a/include/scsi/libiscsi_tcp.h b/include/scsi/libiscsi_tcp.h index ef53d4bea28a0..a6e63db75d674 100644 --- a/include/scsi/libiscsi_tcp.h +++ b/include/scsi/libiscsi_tcp.h @@ -66,6 +66,7 @@ struct iscsi_tcp_conn { struct iscsi_tcp_task { uint32_t exp_datasn; / expected target's R2TSN/DataSN / + uint32_t data_in_bytes; / Data-In payload received / int data_offset; struct iscsi_r2t_info r2t; /* in progress solict R2T */ struct iscsi_pool r2tpool;
3/2	2026/10/08 05:20	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 4954 output: 40 thoughts: 315 Thoughts: Evaluating the Patch's Suitability for Syzkaller Fuzzing Okay, so I need to decide if this patch is a good candidate for fuzzing with syzkaller. I'm going to follow the core triage philosophy here. First, and foremost, is reachability. If the code isn't reachable in a standard virtualized environment (think GCE or QEMU using software-emulated devices), then it's a no-go. I can't waste time on unreachable code. I'm also not going to blindly trust claims of "no functional change" or refactorings; I need to verify that myself. New or modified assertions in reachable code? That's a definite "yes" for fuzzing. Now, let's look at the patch itself. It's touching `drivers/scsi/libiscsi_tcp.c` and `include/scsi/libiscsi_tcp.h`. My immediate thought is, what uses `libiscsi_tcp`? I need to figure out the dependencies, figure out if this code path is actually hit, which means I'll need to use grep or the codesearch tools to figure out the broader context of the changes and how the code is invoked. I can't start fuzzing until I have a strong understanding of where this code lives in the execution path.
4/2	2026/10/08 05:20	tool	grepper	0m Args: { "Expression": "(iscsi_tcp\|libiscsi_tcp)", "PathPrefixes": [ "drivers/scsi/" ] } Results: { "Output": "\nFull output is too long, showing 200 out of 859 lines.\nUse more precise expression or PathPrefixes if possible.\n\nNumber of matching lines per file (10 files in total):\ndrivers/scsi/Kconfig:1\ndrivers/scsi/Makefile:3\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:3\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:3\ndrivers/scsi/cxgbi/libcxgbi.c:29\ndrivers/scsi/cxgbi/libcxgbi.h:2\ndrivers/scsi/iscsi_tcp.c:50\ndrivers/scsi/iscsi_tcp.h:2\ndrivers/scsi/libiscsi.c:1\ndrivers/scsi/libiscsi_tcp.c:117\n\ndrivers/scsi/Kconfig=303=config ISCSI_TCP\n--\ndrivers/scsi/Kconfig-317-\t To compile this driver as a module, choose M here: the\ndrivers/scsi/Kconfig:318:\t module will be called iscsi_tcp.\ndrivers/scsi/Kconfig-319-\n--\ndrivers/scsi/Makefile=70=obj-$(CONFIG_QEDF)\t\t+= qedf/\ndrivers/scsi/Makefile:71:obj-$(CONFIG_ISCSI_TCP) \t+= libiscsi.o\tlibiscsi_tcp.o iscsi_tcp.o\ndrivers/scsi/Makefile-72-obj-$(CONFIG_INFINIBAND_ISER) \t+= libiscsi.o\n--\ndrivers/scsi/Makefile=155=obj-$(CONFIG_PS3_ROM)\t\t+= ps3rom.o\ndrivers/scsi/Makefile:156:obj-$(CONFIG_SCSI_CXGB3_ISCSI)\t+= libiscsi.o libiscsi_tcp.o cxgbi/\ndrivers/scsi/Makefile:157:obj-$(CONFIG_SCSI_CXGB4_ISCSI)\t+= libiscsi.o libiscsi_tcp.o cxgbi/\ndrivers/scsi/Makefile-158-obj-$(CONFIG_SCSI_BNX2_ISCSI)\t+= libiscsi.o bnx2i/\n--\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c=104=static struct iscsi_transport cxgb3i_iscsi_transport = {\n--\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-121-\t.unbind_conn\t= iscsi_conn_unbind,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:122:\t.destroy_conn\t= iscsi_tcp_conn_teardown,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-123-\t.start_conn\t= iscsi_conn_start,\n--\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-130-\t/* task /\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:131:\t.init_task\t= iscsi_tcp_task_init,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:132:\t.xmit_task\t= iscsi_tcp_task_xmit,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-133-\t.cleanup_task\t= cxgbi_cleanup_task,\n--\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c=122=static struct iscsi_transport cxgb4i_iscsi_transport = {\n--\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-138-\t.unbind_conn\t= iscsi_conn_unbind,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:139:\t.destroy_conn\t= iscsi_tcp_conn_teardown,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-140-\t.start_conn\t\t= iscsi_conn_start,\n--\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-147-\t/ task /\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:148:\t.init_task\t= iscsi_tcp_task_init,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:149:\t.xmit_task\t= iscsi_tcp_task_xmit,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-150-\t.cleanup_task\t= cxgbi_cleanup_task,\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1351=static void task_release_itt(struct iscsi_task task, itt_t hdr_itt)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1353-\tstruct scsi_cmnd sc = task-\u003esc;\ndrivers/scsi/cxgbi/libcxgbi.c:1354:\tstruct iscsi_tcp_conn tcp_conn = task-\u003econn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1355-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1382=static int task_reserve_itt(struct iscsi_task task, itt_t hdr_itt)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1386-\tstruct iscsi_session sess = conn-\u003esession;\ndrivers/scsi/cxgbi/libcxgbi.c:1387:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1388-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1425=void cxgbi_parse_pdu_itt(struct iscsi_conn conn, itt_t itt, int idx, int age)\ndrivers/scsi/cxgbi/libcxgbi.c-1426-{\ndrivers/scsi/cxgbi/libcxgbi.c:1427:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1428-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1461=EXPORT_SYMBOL_GPL(cxgbi_conn_tx_open);\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1463-/\ndrivers/scsi/cxgbi/libcxgbi.c:1464: * pdu receive, interact with libiscsi_tcp\ndrivers/scsi/cxgbi/libcxgbi.c-1465- /\ndrivers/scsi/cxgbi/libcxgbi.c=1466=static inline int read_pdu_skb(struct iscsi_conn conn,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1473-\ndrivers/scsi/cxgbi/libcxgbi.c:1474:\tbytes_read = iscsi_tcp_recv_skb(conn, skb, offset, offloaded, \u0026status);\ndrivers/scsi/cxgbi/libcxgbi.c-1475-\tswitch (status) {\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1508=skb_read_pdu_bhs(struct cxgbi_sock csk, struct iscsi_conn conn,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1510-{\ndrivers/scsi/cxgbi/libcxgbi.c:1511:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1512-\tint err;\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1517-\ndrivers/scsi/cxgbi/libcxgbi.c:1518:\tif (!iscsi_tcp_recv_segment_is_hdr(tcp_conn)) {\ndrivers/scsi/cxgbi/libcxgbi.c-1519-\t\tpr_info(\"conn 0x%p, skb 0x%p, not hdr.\\n\", conn, skb);\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1543-\t\tif (task \u0026\u0026 task-\u003esc) {\ndrivers/scsi/cxgbi/libcxgbi.c:1544:\t\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1545-\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1562=static int skb_read_pdu_data(struct iscsi_conn conn, struct sk_buff lskb,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1564-{\ndrivers/scsi/cxgbi/libcxgbi.c:1565:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1566-\tbool offloaded = 0;\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1580-\ndrivers/scsi/cxgbi/libcxgbi.c:1581:\tif (iscsi_tcp_recv_segment_is_hdr(tcp_conn))\ndrivers/scsi/cxgbi/libcxgbi.c-1582-\t\treturn 0;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1885=int cxgbi_conn_alloc_pdu(struct iscsi_task task, u8 op)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1888-\tstruct iscsi_session session = task-\u003econn-\u003esession;\ndrivers/scsi/cxgbi/libcxgbi.c:1889:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1890-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1892-\tstruct cxgbi_sock csk = cconn-\u003ecep ? cconn-\u003ecep-\u003ecsk : NULL;\ndrivers/scsi/cxgbi/libcxgbi.c:1893:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1894-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2061=cxgbi_prep_iso_info(struct iscsi_task task, struct sk_buff skb,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2068-\tstruct iscsi_session session = conn-\u003esession;\ndrivers/scsi/cxgbi/libcxgbi.c:2069:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2070-\tu32 burst_size = 0, r2t_dlength = 0, dlength;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2144=int cxgbi_conn_init_pdu(struct iscsi_task task, unsigned int offset,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2147-\tstruct iscsi_conn conn = task-\u003econn;\ndrivers/scsi/cxgbi/libcxgbi.c:2148:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2149-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2361=int cxgbi_conn_xmit_pdu(struct iscsi_task task)\ndrivers/scsi/cxgbi/libcxgbi.c-2362-{\ndrivers/scsi/cxgbi/libcxgbi.c:2363:\tstruct iscsi_tcp_conn tcp_conn = task-\u003econn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2364-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c:2365:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2366-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2470=void cxgbi_cleanup_task(struct iscsi_task task)\ndrivers/scsi/cxgbi/libcxgbi.c-2471-{\ndrivers/scsi/cxgbi/libcxgbi.c:2472:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2473-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2500-\ndrivers/scsi/cxgbi/libcxgbi.c:2501:\tiscsi_tcp_cleanup_task(task);\ndrivers/scsi/cxgbi/libcxgbi.c-2502-}\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2527=static int cxgbi_conn_max_xmit_dlength(struct iscsi_conn conn)\ndrivers/scsi/cxgbi/libcxgbi.c-2528-{\ndrivers/scsi/cxgbi/libcxgbi.c:2529:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2530-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2546=static int cxgbi_conn_max_recv_dlength(struct iscsi_conn conn)\ndrivers/scsi/cxgbi/libcxgbi.c-2547-{\ndrivers/scsi/cxgbi/libcxgbi.c:2548:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2549-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2568=int cxgbi_set_conn_param(struct iscsi_cls_conn cls_conn,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2571-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c:2572:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2573-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2596-\tcase ISCSI_PARAM_MAX_R2T:\ndrivers/scsi/cxgbi/libcxgbi.c:2597:\t\treturn iscsi_tcp_set_max_r2t(conn, buf);\ndrivers/scsi/cxgbi/libcxgbi.c-2598-\tcase ISCSI_PARAM_MAX_RECV_DLENGTH:\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2644=cxgbi_create_conn(struct iscsi_cls_session cls_session, u32 cid)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2647-\tstruct iscsi_conn conn;\ndrivers/scsi/cxgbi/libcxgbi.c:2648:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/cxgbi/libcxgbi.c-2649-\tstruct cxgbi_conn cconn;\ndrivers/scsi/cxgbi/libcxgbi.c-2650-\ndrivers/scsi/cxgbi/libcxgbi.c:2651:\tcls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(cconn), cid);\ndrivers/scsi/cxgbi/libcxgbi.c-2652-\tif (!cls_conn)\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2668=int cxgbi_bind_conn(struct iscsi_cls_session cls_session,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2672-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c:2673:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2674-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2717-\t/ init recv engine /\ndrivers/scsi/cxgbi/libcxgbi.c:2718:\tiscsi_tcp_hdr_recv_prep(tcp_conn);\ndrivers/scsi/cxgbi/libcxgbi.c-2719-\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2726=struct iscsi_cls_session cxgbi_create_session(struct iscsi_endpoint ep,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2748-\t\t\t\t\tcmds_max, 0,\ndrivers/scsi/cxgbi/libcxgbi.c:2749:\t\t\t\t\tsizeof(struct iscsi_tcp_task) +\ndrivers/scsi/cxgbi/libcxgbi.c-2750-\t\t\t\t\tsizeof(struct cxgbi_task_data),\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2755-\tsession = cls_session-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c:2756:\tif (iscsi_tcp_r2tpool_alloc(session))\ndrivers/scsi/cxgbi/libcxgbi.c-2757-\t\tgoto remove_session;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2769=void cxgbi_destroy_session(struct iscsi_cls_session cls_session)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2773-\ndrivers/scsi/cxgbi/libcxgbi.c:2774:\tiscsi_tcp_r2tpool_free(cls_session-\u003edd_data);\ndrivers/scsi/cxgbi/libcxgbi.c-2775-\tiscsi_session_teardown(cls_session);\n--\ndrivers/scsi/cxgbi/libcxgbi.h-27-#include \u003cscsi/scsi_device.h\u003e\ndrivers/scsi/cxgbi/libcxgbi.h:28:#include \u003cscsi/libiscsi_tcp.h\u003e\ndrivers/scsi/cxgbi/libcxgbi.h-29-\n--\ndrivers/scsi/cxgbi/libcxgbi.h=539=struct cxgbi_task_data {\n--\ndrivers/scsi/cxgbi/libcxgbi.h-555-#define iscsi_task_cxgbi_data(task) \\\ndrivers/scsi/cxgbi/libcxgbi.h:556:\t((task)-\u003edd_data + sizeof(struct iscsi_tcp_task))\ndrivers/scsi/cxgbi/libcxgbi.h-557-\n--\ndrivers/scsi/iscsi_tcp.c-39-\ndrivers/scsi/iscsi_tcp.c:40:#include \"iscsi_tcp.h\"\ndrivers/scsi/iscsi_tcp.c-41-\n--\ndrivers/scsi/iscsi_tcp.c=59=static int iscsi_sw_tcp_dbg;\ndrivers/scsi/iscsi_tcp.c:60:module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,\ndrivers/scsi/iscsi_tcp.c-61-\t\t S_IRUGO \| S_IWUSR);\ndrivers/scsi/iscsi_tcp.c:62:MODULE_PARM_DESC(debug_iscsi_tcp, \"Turn on debugging for iscsi_tcp module \"\n\n" }
5/2	2026/10/08 05:20	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11214 output: 39 thoughts: 101 Thoughts: Analyzing the iSCSI TCP Implementation Okay, so I'm looking at `drivers/scsi/iscsi_tcp.c`. Right, this is the iSCSI implementation over TCP, obviously. I need to understand how this is structured and, specifically, how it interfaces with `libiscsi_tcp.c`. My focus right now is really to grasp that relationship. I'm going to quickly check `drivers/scsi/iscsi_tcp.c` itself. I think the fastest way to understand the connection is probably to use `grep` and look for instances of `libiscsi_tcp` within `drivers/scsi/iscsi_tcp.c`, or just inspect the file directly to see how they're related. That's the best way to get a quick overview of the code, and their interaction.
6/2	2026/10/08 05:21	tool	grepper	0m Args: { "Expression": "iscsi_tcp_", "PathPrefixes": [ "drivers/scsi/iscsi_tcp.c" ] } Results: { "Output": "\nFull output is too long, showing 200 out of 212 lines.\nUse more precise expression or PathPrefixes if possible.\n\nNumber of matching lines per file (1 files in total):\ndrivers/scsi/iscsi_tcp.c:44\n\ndrivers/scsi/iscsi_tcp.c=84=static int iscsi_sw_tcp_recv(read_descriptor_t rd_desc, struct sk_buff skb,\n--\ndrivers/scsi/iscsi_tcp.c-94-\t\tstatus = 0;\ndrivers/scsi/iscsi_tcp.c:95:\t\tconsumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, \u0026status);\ndrivers/scsi/iscsi_tcp.c-96-\t\toffset += consumed;\n--\ndrivers/scsi/iscsi_tcp.c=129=static void iscsi_sw_tcp_recv_data(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-130-{\ndrivers/scsi/iscsi_tcp.c:131:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-132-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-136-\t/\ndrivers/scsi/iscsi_tcp.c:137:\t * Use rd_desc to pass 'conn' to iscsi_tcp_recv.\ndrivers/scsi/iscsi_tcp.c-138-\t * We set count to 1 because we want the network layer to\ndrivers/scsi/iscsi_tcp.c:139:\t * hand us all the skbs that are available. iscsi_tcp_recv\ndrivers/scsi/iscsi_tcp.c-140-\t * handled pdus that cross buffers or pdus that still need data.\n--\ndrivers/scsi/iscsi_tcp.c-148-\t * unmap it now. /\ndrivers/scsi/iscsi_tcp.c:149:\tiscsi_tcp_segment_unmap(\u0026tcp_conn-\u003ein.segment);\ndrivers/scsi/iscsi_tcp.c-150-\n--\ndrivers/scsi/iscsi_tcp.c=154=static void iscsi_sw_tcp_recv_data_work(struct work_struct work)\n--\ndrivers/scsi/iscsi_tcp.c-157-\t\t\t\t\t recvwork);\ndrivers/scsi/iscsi_tcp.c:158:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-159-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=167=static void iscsi_sw_tcp_data_ready(struct sock sk)\n--\ndrivers/scsi/iscsi_tcp.c-169-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\ndrivers/scsi/iscsi_tcp.c:170:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-171-\tstruct iscsi_conn conn;\n--\ndrivers/scsi/iscsi_tcp.c=191=static void iscsi_sw_tcp_state_change(struct sock sk)\ndrivers/scsi/iscsi_tcp.c-192-{\ndrivers/scsi/iscsi_tcp.c:193:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-194-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\n--\ndrivers/scsi/iscsi_tcp.c=220=static void iscsi_sw_tcp_write_space(struct sock sk)\n--\ndrivers/scsi/iscsi_tcp.c-222-\tstruct iscsi_conn conn;\ndrivers/scsi/iscsi_tcp.c:223:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-224-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\n--\ndrivers/scsi/iscsi_tcp.c=245=static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-246-{\ndrivers/scsi/iscsi_tcp.c:247:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-248-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=264=iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-265-{\ndrivers/scsi/iscsi_tcp.c:266:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-267-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-292- /\ndrivers/scsi/iscsi_tcp.c:293:static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn tcp_conn,\ndrivers/scsi/iscsi_tcp.c-294-\t\t\t\t struct iscsi_segment segment)\n--\ndrivers/scsi/iscsi_tcp.c-300-\ndrivers/scsi/iscsi_tcp.c:301:\twhile (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {\ndrivers/scsi/iscsi_tcp.c-302-\t\tstruct scatterlist sg;\n--\ndrivers/scsi/iscsi_tcp.c-329-\t\tif (r \u003c 0) {\ndrivers/scsi/iscsi_tcp.c:330:\t\t\tiscsi_tcp_segment_unmap(segment);\ndrivers/scsi/iscsi_tcp.c-331-\t\t\treturn r;\n--\ndrivers/scsi/iscsi_tcp.c=342=static int iscsi_sw_tcp_xmit(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-343-{\ndrivers/scsi/iscsi_tcp.c:344:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-345-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=393=static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-394-{\ndrivers/scsi/iscsi_tcp.c:395:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-396-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=402=static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task task)\n--\ndrivers/scsi/iscsi_tcp.c-405-\tunsigned int noreclaim_flag;\ndrivers/scsi/iscsi_tcp.c:406:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-407-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-436- /\ndrivers/scsi/iscsi_tcp.c:437:static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn tcp_conn,\ndrivers/scsi/iscsi_tcp.c-438-\t\t\t\t struct iscsi_segment segment)\n--\ndrivers/scsi/iscsi_tcp.c=450=static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn conn, void hdr,\n--\ndrivers/scsi/iscsi_tcp.c-452-{\ndrivers/scsi/iscsi_tcp.c:453:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-454-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-459-\t/ Clear the data segment - needs to be filled in by the\ndrivers/scsi/iscsi_tcp.c:460:\t * caller using iscsi_tcp_send_data_prep() /\ndrivers/scsi/iscsi_tcp.c-461-\tmemset(\u0026tcp_sw_conn-\u003eout.data_segment, 0,\n--\ndrivers/scsi/iscsi_tcp.c-465-\t place the digest into the same buffer. We make\ndrivers/scsi/iscsi_tcp.c:466:\t * sure that both iscsi_tcp_task and mtask have\ndrivers/scsi/iscsi_tcp.c-467-\t * sufficient room.\n--\ndrivers/scsi/iscsi_tcp.c-469-\tif (conn-\u003ehdrdgst_en) {\ndrivers/scsi/iscsi_tcp.c:470:\t\tiscsi_tcp_dgst_header(hdr, hdrlen, hdr + hdrlen);\ndrivers/scsi/iscsi_tcp.c-471-\t\thdrlen += ISCSI_DIGEST_SIZE;\n--\ndrivers/scsi/iscsi_tcp.c=489=iscsi_sw_tcp_send_data_prep(struct iscsi_conn conn, struct scatterlist sg,\n--\ndrivers/scsi/iscsi_tcp.c-492-{\ndrivers/scsi/iscsi_tcp.c:493:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-494-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=515=iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn conn, void data,\n--\ndrivers/scsi/iscsi_tcp.c-517-{\ndrivers/scsi/iscsi_tcp.c:518:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-519-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=566=static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task task, uint8_t opcode)\ndrivers/scsi/iscsi_tcp.c-567-{\ndrivers/scsi/iscsi_tcp.c:568:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-569-\n--\ndrivers/scsi/iscsi_tcp.c=576=iscsi_sw_tcp_conn_create(struct iscsi_cls_session cls_session,\n--\ndrivers/scsi/iscsi_tcp.c-580-\tstruct iscsi_cls_conn cls_conn;\ndrivers/scsi/iscsi_tcp.c:581:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-582-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\ndrivers/scsi/iscsi_tcp.c-583-\ndrivers/scsi/iscsi_tcp.c:584:\tcls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(tcp_sw_conn),\ndrivers/scsi/iscsi_tcp.c-585-\t\t\t\t\tconn_idx);\n--\ndrivers/scsi/iscsi_tcp.c=600=static void iscsi_sw_tcp_release_conn(struct iscsi_conn conn)\ndrivers/scsi/iscsi_tcp.c-601-{\ndrivers/scsi/iscsi_tcp.c:602:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-603-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=632=static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn cls_conn)\n--\ndrivers/scsi/iscsi_tcp.c-636-\tiscsi_sw_tcp_release_conn(conn);\ndrivers/scsi/iscsi_tcp.c:637:\tiscsi_tcp_conn_teardown(cls_conn);\ndrivers/scsi/iscsi_tcp.c-638-}\n--\ndrivers/scsi/iscsi_tcp.c=640=static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn cls_conn, int flag)\n--\ndrivers/scsi/iscsi_tcp.c-642-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c:643:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-644-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c=664=iscsi_sw_tcp_conn_bind(struct iscsi_cls_session cls_session,\n--\ndrivers/scsi/iscsi_tcp.c-668-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c:669:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-670-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-708-\t /\ndrivers/scsi/iscsi_tcp.c:709:\tiscsi_tcp_hdr_recv_prep(tcp_conn);\ndrivers/scsi/iscsi_tcp.c-710-\treturn 0;\n--\ndrivers/scsi/iscsi_tcp.c=717=static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn cls_conn,\n--\ndrivers/scsi/iscsi_tcp.c-721-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c:722:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-723-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-738-\tcase ISCSI_PARAM_MAX_R2T:\ndrivers/scsi/iscsi_tcp.c:739:\t\treturn iscsi_tcp_set_max_r2t(conn, buf);\ndrivers/scsi/iscsi_tcp.c-740-\tdefault:\n--\ndrivers/scsi/iscsi_tcp.c=747=static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn cls_conn,\n--\ndrivers/scsi/iscsi_tcp.c-751-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\ndrivers/scsi/iscsi_tcp.c:752:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-753-\tstruct sockaddr_in6 addr;\n--\ndrivers/scsi/iscsi_tcp.c=804=static int iscsi_sw_tcp_host_get_param(struct Scsi_Host shost,\n--\ndrivers/scsi/iscsi_tcp.c-809-\tstruct iscsi_conn conn;\ndrivers/scsi/iscsi_tcp.c:810:\tstruct iscsi_tcp_conn tcp_conn;\ndrivers/scsi/iscsi_tcp.c-811-\tstruct iscsi_sw_tcp_conn tcp_sw_conn;\n--\ndrivers/scsi/iscsi_tcp.c=859=iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn cls_conn,\n--\ndrivers/scsi/iscsi_tcp.c-862-\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c:863:\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-864-\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n--\ndrivers/scsi/iscsi_tcp.c-873-\ndrivers/scsi/iscsi_tcp.c:874:\tiscsi_tcp_conn_get_stats(cls_conn, stats);\ndrivers/scsi/iscsi_tcp.c-875-}\n--\ndrivers/scsi/iscsi_tcp.c=878=iscsi_sw_tcp_session_create(struct iscsi_endpoint ep, uint16_t cmds_max,\n--\ndrivers/scsi/iscsi_tcp.c-913-\t\t\t\t\t cmds_max, 0,\ndrivers/scsi/iscsi_tcp.c:914:\t\t\t\t\t sizeof(struct iscsi_tcp_task) +\ndrivers/scsi/iscsi_tcp.c-915-\t\t\t\t\t sizeof(struct iscsi_sw_tcp_hdrbuf),\n--\ndrivers/scsi/iscsi_tcp.c-920-\ndrivers/scsi/iscsi_tcp.c:921:\tif (iscsi_tcp_r2tpool_alloc(session))\ndrivers/scsi/iscsi_tcp.c-922-\t\tgoto remove_session;\n--\ndrivers/scsi/iscsi_tcp.c=938=static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)\n\n" }
7/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 16647 output: 36 thoughts: 95 Thoughts: Here's my thought process, as if I were considering this myself: Investigating Syzkaller's iSCSI Capabilities Okay, so I want to understand how effectively syzkaller can test the interaction between the kernel and iSCSI, specifically the `iscsi_tcp` transport. The first thing I need to do is establish what support, if any, syzkaller already has in place for iSCSI. Does it have pre-existing descriptions of iSCSI functionality? Does it understand the relevant netlink interfaces or socket options used by iSCSI? Before I dive too deep into manual code diving, let's take a shortcut. Let's start with a quick and dirty search within the kernel source tree. I'll grep for key iSCSI identifiers like `open_iscsi`, `iscsi_netlink`, `iscsi_if` and `scsi_transport_iscsi`. This should quickly reveal any existing syzkaller integration points, or at least give me a starting point to assess how the iSCSI subsystems are exposed to the kernel. This will save me from having to re-invent the wheel, and immediately establish if I need to build a new target for fuzzing.
8/2	2026/10/08 05:21	tool	grepper	0m Args: { "Expression": "NETLINK_ISCSI", "PathPrefixes": [ "include/", "drivers/scsi/" ] } Results: { "Output": "drivers/scsi/scsi_transport_iscsi.c=4943=static __init int iscsi_transport_init(void)\n--\ndrivers/scsi/scsi_transport_iscsi.c-4982-\ndrivers/scsi/scsi_transport_iscsi.c:4983:\tnls = netlink_kernel_create(\u0026init_net, NETLINK_ISCSI, \u0026cfg);\ndrivers/scsi/scsi_transport_iscsi.c-4984-\tif (!nls) {\n--\ndrivers/scsi/scsi_transport_iscsi.c=5039=MODULE_VERSION(ISCSI_TRANSPORT_VERSION);\ndrivers/scsi/scsi_transport_iscsi.c:5040:MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_ISCSI);\n--\ninclude/scsi/iscsi_if.h=318=struct iscsi_iface_param_info {\n--\ninclude/scsi/iscsi_if.h-330- * ISCSI_KEVENT_PATH_REQ is defined separately and comes after the\ninclude/scsi/iscsi_if.h:331: * struct iscsi_uevent in the NETLINK_ISCSI message.\ninclude/scsi/iscsi_if.h-332- /\n--\ninclude/uapi/linux/netlink.h-16-#define NETLINK_SELINUX\t\t7\t/ SELinux event notifications /\ninclude/uapi/linux/netlink.h:17:#define NETLINK_ISCSI\t\t8\t/ Open-iSCSI /\ninclude/uapi/linux/netlink.h-18-#define NETLINK_AUDIT\t\t9\t/ auditing */\n" }
9/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 17484 output: 45 thoughts: 107 Thoughts: Exploring the Linux iSCSI Netlink Interface Okay, so NETLINK_ISCSI is a thing in the Linux netlink framework. That's interesting. The implication is that user space can directly interact with iSCSI through netlink messages. I need to understand what this interface offers. Let's delve into the `drivers/scsi/scsi_transport_iscsi.c` source code. The core question is: can user space leverage this netlink interface to create iSCSI sessions, manage socket bindings, and so forth? Time to check the `iscsi_if_recv_msg` function in that file; that should be the entry point for handling these netlink requests. Hopefully, that gives me a better handle on the potential of this interface.
10/2	2026/10/08 05:21	tool	grepper	0m Args: { "Expression": "iscsi_if_recv_msg", "PathPrefixes": [ "drivers/scsi/scsi_transport_iscsi.c" ] } Results: { "Output": "drivers/scsi/scsi_transport_iscsi.c=3882=static int\ndrivers/scsi/scsi_transport_iscsi.c:3883:iscsi_if_recv_msg(struct sk_buff skb, struct nlmsghdr nlh, uint32_t group)\ndrivers/scsi/scsi_transport_iscsi.c-3884-{\n--\ndrivers/scsi/scsi_transport_iscsi.c-4048-/\ndrivers/scsi/scsi_transport_iscsi.c:4049: * Get message from skb. Each message is processed by iscsi_if_recv_msg.\ndrivers/scsi/scsi_transport_iscsi.c-4050- * Malformed skbs with wrong lengths or invalid creds are not processed.\n--\ndrivers/scsi/scsi_transport_iscsi.c=4053=iscsi_if_rx(struct sk_buff *skb)\n--\ndrivers/scsi/scsi_transport_iscsi.c-4076-\ndrivers/scsi/scsi_transport_iscsi.c:4077:\t\terr = iscsi_if_recv_msg(skb, nlh, \u0026group);\ndrivers/scsi/scsi_transport_iscsi.c-4078-\t\tif (err) {\n" }
11/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 18160 output: 44 thoughts: 29 Thoughts: Here's a summary of my thought process, as requested: Diving into `scsi_transport_iscsi.c` Okay, time to get my hands dirty. I'm focusing on the `drivers/scsi/scsi_transport_iscsi.c` file – it's where the iSCSI transport layer lives, so it should be the right place to begin investigating whatever SCSI-related issue I'm working on. Specifically, I'm directing my attention to around line 3882. That area should have something interesting for me – hopefully the function or code block I'm after, or at least something relevant to the problem I'm trying to solve. I have a hunch... or maybe just a vague recollection... that something in that vicinity is related to [insert specific issue related to the work]. Let's see what's there. Time to start digging and see what I can find.
12/2	2026/10/08 05:21	tool	read-file	0m Args: { "File": "drivers/scsi/scsi_transport_iscsi.c", "FirstLine": 3882, "LineCount": 60 } Results: { "Contents": "3882:\tstatic int\n3883:\tiscsi_if_recv_msg(struct sk_buff skb, struct nlmsghdr nlh, uint32_t group)\n3884:\t{\n3885:\t\tint err = 0;\n3886:\t\tu32 portid;\n3887:\t\tstruct iscsi_uevent ev = nlmsg_data(nlh);\n3888:\t\tstruct iscsi_transport transport = NULL;\n3889:\t\tstruct iscsi_internal priv;\n3890:\t\tstruct iscsi_cls_session session;\n3891:\t\tstruct iscsi_endpoint ep = NULL;\n3892:\t\tu32 rlen;\n3893:\t\n3894:\t\tif (!netlink_capable(skb, CAP_SYS_ADMIN))\n3895:\t\t\treturn -EPERM;\n3896:\t\n3897:\t\tif (nlh-\u003enlmsg_type == ISCSI_UEVENT_PATH_UPDATE)\n3898:\t\t\tgroup = ISCSI_NL_GRP_UIP;\n3899:\t\telse\n3900:\t\t\tgroup = ISCSI_NL_GRP_ISCSID;\n3901:\t\n3902:\t\tpriv = iscsi_if_transport_lookup(iscsi_ptr(ev-\u003etransport_handle));\n3903:\t\tif (!priv)\n3904:\t\t\treturn -EINVAL;\n3905:\t\ttransport = priv-\u003eiscsi_transport;\n3906:\t\n3907:\t\tif (!try_module_get(transport-\u003eowner))\n3908:\t\t\treturn -EINVAL;\n3909:\t\n3910:\t\tportid = NETLINK_CB(skb).portid;\n3911:\t\n3912:\t\t/\n3913:\t\t Even though the remaining payload may not be regarded as nlattr,\n3914:\t\t * (like address or something else), calculate the remaining length\n3915:\t\t * here to ease following length checks.\n3916:\t\t /\n3917:\t\trlen = nlmsg_attrlen(nlh, sizeof(ev));\n3918:\t\n3919:\t\tswitch (nlh-\u003enlmsg_type) {\n3920:\t\tcase ISCSI_UEVENT_CREATE_SESSION:\n3921:\t\t\terr = iscsi_if_create_session(priv, ep, ev,\n3922:\t\t\t\t\t\t portid,\n3923:\t\t\t\t\t\t ev-\u003eu.c_session.initial_cmdsn,\n3924:\t\t\t\t\t\t ev-\u003eu.c_session.cmds_max,\n3925:\t\t\t\t\t\t ev-\u003eu.c_session.queue_depth);\n3926:\t\t\tbreak;\n3927:\t\tcase ISCSI_UEVENT_CREATE_BOUND_SESSION:\n3928:\t\t\tep = iscsi_lookup_endpoint(ev-\u003eu.c_bound_session.ep_handle);\n3929:\t\t\tif (!ep) {\n3930:\t\t\t\terr = -EINVAL;\n3931:\t\t\t\tbreak;\n3932:\t\t\t}\n3933:\t\n3934:\t\t\terr = iscsi_if_create_session(priv, ep, ev,\n3935:\t\t\t\t\t\tportid,\n3936:\t\t\t\t\t\tev-\u003eu.c_bound_session.initial_cmdsn,\n3937:\t\t\t\t\t\tev-\u003eu.c_bound_session.cmds_max,\n3938:\t\t\t\t\t\tev-\u003eu.c_bound_session.queue_depth);\n3939:\t\t\tiscsi_put_endpoint(ep);\n3940:\t\t\tbreak;\n3941:\t\tcase ISCSI_UEVENT_DESTROY_SESSION:\n" }
13/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 19402 output: 44 thoughts: 24 Thoughts: Okay, here's my attempt at summarizing that thought process, keeping in mind the expert user: Deep Dive into iSCSI Connection Binding Alright, let's circle back to `iscsi_if_recv_msg`. I'm going to revisit that function and really drill down into the connection binding aspect. I need to refresh my mental model of precisely how a connection is established, and how that binding process plays out within that particular function. I want to understand the control flow, the data structures involved, and any potential points where issues might arise during the initial handshake and subsequent connection establishment. Let's see how the connection is actually bound. Let's dig deeper.
14/2	2026/10/08 05:21	tool	read-file	0m Args: { "File": "drivers/scsi/scsi_transport_iscsi.c", "FirstLine": 3942, "LineCount": 60 } Results: { "Contents": "3942:\t\t\tsession = iscsi_session_lookup(ev-\u003eu.d_session.sid);\n3943:\t\t\tif (!session)\n3944:\t\t\t\terr = -EINVAL;\n3945:\t\t\telse if (iscsi_session_has_conns(ev-\u003eu.d_session.sid))\n3946:\t\t\t\terr = -EBUSY;\n3947:\t\t\telse\n3948:\t\t\t\ttransport-\u003edestroy_session(session);\n3949:\t\t\tbreak;\n3950:\t\tcase ISCSI_UEVENT_DESTROY_SESSION_ASYNC:\n3951:\t\t\tsession = iscsi_session_lookup(ev-\u003eu.d_session.sid);\n3952:\t\t\tif (!session)\n3953:\t\t\t\terr = -EINVAL;\n3954:\t\t\telse if (iscsi_session_has_conns(ev-\u003eu.d_session.sid))\n3955:\t\t\t\terr = -EBUSY;\n3956:\t\t\telse {\n3957:\t\t\t\tunsigned long flags;\n3958:\t\n3959:\t\t\t\t/* Prevent this session from being found again */\n3960:\t\t\t\tspin_lock_irqsave(\u0026sesslock, flags);\n3961:\t\t\t\tlist_del_init(\u0026session-\u003esess_list);\n3962:\t\t\t\tspin_unlock_irqrestore(\u0026sesslock, flags);\n3963:\t\n3964:\t\t\t\tqueue_work(system_dfl_wq, \u0026session-\u003edestroy_work);\n3965:\t\t\t}\n3966:\t\t\tbreak;\n3967:\t\tcase ISCSI_UEVENT_UNBIND_SESSION:\n3968:\t\t\tsession = iscsi_session_lookup(ev-\u003eu.d_session.sid);\n3969:\t\t\tif (session)\n3970:\t\t\t\tqueue_work(session-\u003eworkq, \u0026session-\u003eunbind_work);\n3971:\t\t\telse\n3972:\t\t\t\terr = -EINVAL;\n3973:\t\t\tbreak;\n3974:\t\tcase ISCSI_UEVENT_SET_PARAM:\n3975:\t\t\terr = iscsi_if_set_param(transport, ev, rlen);\n3976:\t\t\tbreak;\n3977:\t\tcase ISCSI_UEVENT_CREATE_CONN:\n3978:\t\tcase ISCSI_UEVENT_DESTROY_CONN:\n3979:\t\tcase ISCSI_UEVENT_STOP_CONN:\n3980:\t\tcase ISCSI_UEVENT_START_CONN:\n3981:\t\tcase ISCSI_UEVENT_BIND_CONN:\n3982:\t\tcase ISCSI_UEVENT_SEND_PDU:\n3983:\t\t\terr = iscsi_if_transport_conn(transport, nlh, rlen);\n3984:\t\t\tbreak;\n3985:\t\tcase ISCSI_UEVENT_GET_STATS:\n3986:\t\t\terr = iscsi_if_get_stats(transport, nlh);\n3987:\t\t\tbreak;\n3988:\t\tcase ISCSI_UEVENT_TRANSPORT_EP_CONNECT:\n3989:\t\tcase ISCSI_UEVENT_TRANSPORT_EP_POLL:\n3990:\t\tcase ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:\n3991:\t\tcase ISCSI_UEVENT_TRANSPORT_EP_CONNECT_THROUGH_HOST:\n3992:\t\t\terr = iscsi_if_transport_ep(transport, ev, nlh-\u003enlmsg_type, rlen);\n3993:\t\t\tbreak;\n3994:\t\tcase ISCSI_UEVENT_TGT_DSCVR:\n3995:\t\t\terr = iscsi_tgt_dscvr(transport, ev, rlen);\n3996:\t\t\tbreak;\n3997:\t\tcase ISCSI_UEVENT_SET_HOST_PARAM:\n3998:\t\t\terr = iscsi_set_host_param(transport, ev, rlen);\n3999:\t\t\tbreak;\n4000:\t\tcase ISCSI_UEVENT_PATH_UPDATE:\n4001:\t\t\terr = iscsi_set_path(transport, ev, rlen);\n" }
15/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 20666 output: 45 thoughts: 44 Thoughts: Here's my summary, as if I were thinking it: Analyzing iSCSI Connection Binding Okay, let's dive into the `iscsi_if_transport_conn` function. Specifically, I'm focusing on the `ISCSI_UEVENT_BIND_CONN` case within that function. This is where the magic happens, the point where connections are bound, and where I can gain insight into the process of iSCSI transport. Time to dig in!
16/2	2026/10/08 05:21	tool	grepper	0m Args: { "Expression": "iscsi_if_transport_conn", "PathPrefixes": [ "drivers/scsi/scsi_transport_iscsi.c" ] } Results: { "Output": "drivers/scsi/scsi_transport_iscsi.c=3703=iscsi_get_host_stats(struct iscsi_transport transport, struct nlmsghdr nlh)\n--\ndrivers/scsi/scsi_transport_iscsi.c-3771-\ndrivers/scsi/scsi_transport_iscsi.c:3772:static int iscsi_if_transport_conn(struct iscsi_transport transport,\ndrivers/scsi/scsi_transport_iscsi.c-3773-\t\t\t\t struct nlmsghdr nlh, u32 pdu_len)\n--\ndrivers/scsi/scsi_transport_iscsi.c=3883=iscsi_if_recv_msg(struct sk_buff skb, struct nlmsghdr nlh, uint32_t *group)\n--\ndrivers/scsi/scsi_transport_iscsi.c-3982-\tcase ISCSI_UEVENT_SEND_PDU:\ndrivers/scsi/scsi_transport_iscsi.c:3983:\t\terr = iscsi_if_transport_conn(transport, nlh, rlen);\ndrivers/scsi/scsi_transport_iscsi.c-3984-\t\tbreak;\n" }
17/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 21192 output: 44 thoughts: 15 Thoughts: Okay, let's dive into this. Here's my take on `iscsi_if_transport_conn`: Analyzing `iscsi_if_transport_conn` Alright, let's get into this `iscsi_if_transport_conn` thing. First, I'm thinking about the name itself. The "iscsi" part, obviously, is Internet Small Computer System Interface, that's straightforward. Then "if" likely indicates "interface," meaning this is likely an abstraction layer or a component dealing with iSCSI interactions at a network interface. "transport_conn" strongly suggests this is the structure or module that handles the connection establishment and ongoing communication related to an iSCSI session. I'm immediately considering the context within the broader iSCSI stack. Where does this fit? Is it part of the initiator side, the target side, or something more generic? I'm hoping it's designed to be relatively transport agnostic at its core, but that remains to be seen. I'm looking for fields that would point to the underlying network transport (TCP/IP is the usual suspect, but I'm keeping an open mind for RDMA or other transports, even if unlikely). Key elements I'm expecting to see include: * Network-related information: IP addresses, ports, sockets. Perhaps some state information related to the network connection (connected, disconnected, error states). This is paramount. * iSCSI session identifiers: Target name, initiator name, session ID, connection ID. These are the unique keys to track the iSCSI session. * Data structures for managing iSCSI PDUs (Protocol Data Units): Buffers for receiving and transmitting data, possibly some queuing mechanisms if the implementation is asynchronous. * Security Context: This could include handles to any authentication and/or encryption mechanisms used for the iSCSI connection. CHAP credentials, etc. * State Management: State flags indicating connection status, error conditions, and potential control mechanisms for the session. I'm also anticipating some function pointers or callbacks. This structure is unlikely to be isolated. It probably has functions associated with it for things like handling data transfer, error detection and recovery, and perhaps even session management at the transport layer. Specifically, I'm curious about how it handles things like login/logout requests, data transfers, error reporting, and other iSCSI-specific aspects of the session. Ultimately, I want to understand how this structure facilitates the iSCSI data exchange over the network. Is it a connection-oriented wrapper around the socket, or is it a higher-level abstraction that hides transport details? Is it a key data structure or is it just something to wrap calls and keep the core structures clean? I'm curious to see the implementation details to get a deeper understanding of how this iSCSI connection is managed at a low level. Let's see what we've got.
18/2	2026/10/08 05:21	tool	read-file	0m Args: { "File": "drivers/scsi/scsi_transport_iscsi.c", "FirstLine": 3772, "LineCount": 70 } Results: { "Contents": "3772:\tstatic int iscsi_if_transport_conn(struct iscsi_transport transport,\n3773:\t\t\t\t\t struct nlmsghdr nlh, u32 pdu_len)\n3774:\t{\n3775:\t\tstruct iscsi_uevent ev = nlmsg_data(nlh);\n3776:\t\tstruct iscsi_cls_session session;\n3777:\t\tstruct iscsi_cls_conn conn = NULL;\n3778:\t\tstruct iscsi_endpoint ep;\n3779:\t\tint err = 0;\n3780:\t\n3781:\t\tswitch (nlh-\u003enlmsg_type) {\n3782:\t\tcase ISCSI_UEVENT_CREATE_CONN:\n3783:\t\t\treturn iscsi_if_create_conn(transport, ev);\n3784:\t\tcase ISCSI_UEVENT_DESTROY_CONN:\n3785:\t\t\treturn iscsi_if_destroy_conn(transport, ev);\n3786:\t\tcase ISCSI_UEVENT_STOP_CONN:\n3787:\t\t\tconn = iscsi_conn_lookup(ev-\u003eu.stop_conn.sid,\n3788:\t\t\t\t\t\t ev-\u003eu.stop_conn.cid);\n3789:\t\t\tif (!conn)\n3790:\t\t\t\treturn -EINVAL;\n3791:\t\n3792:\t\t\treturn iscsi_if_stop_conn(conn, ev-\u003eu.stop_conn.flag);\n3793:\t\t}\n3794:\t\n3795:\t\t/\n3796:\t\t The following cmds need to be run under the ep_mutex so in kernel\n3797:\t\t * conn cleanup (ep_disconnect + unbind and conn) is not done while\n3798:\t\t * these are running. They also must not run if we have just run a conn\n3799:\t\t * cleanup because they would set the state in a way that might allow\n3800:\t\t * IO or send IO themselves.\n3801:\t\t */\n3802:\t\tswitch (nlh-\u003enlmsg_type) {\n3803:\t\tcase ISCSI_UEVENT_START_CONN:\n3804:\t\t\tconn = iscsi_conn_lookup(ev-\u003eu.start_conn.sid,\n3805:\t\t\t\t\t\t ev-\u003eu.start_conn.cid);\n3806:\t\t\tbreak;\n3807:\t\tcase ISCSI_UEVENT_BIND_CONN:\n3808:\t\t\tconn = iscsi_conn_lookup(ev-\u003eu.b_conn.sid, ev-\u003eu.b_conn.cid);\n3809:\t\t\tbreak;\n3810:\t\tcase ISCSI_UEVENT_SEND_PDU:\n3811:\t\t\tconn = iscsi_conn_lookup(ev-\u003eu.send_pdu.sid, ev-\u003eu.send_pdu.cid);\n3812:\t\t\tbreak;\n3813:\t\t}\n3814:\t\n3815:\t\tif (!conn)\n3816:\t\t\treturn -EINVAL;\n3817:\t\n3818:\t\tmutex_lock(\u0026conn-\u003eep_mutex);\n3819:\t\tspin_lock_irq(\u0026conn-\u003elock);\n3820:\t\tif (test_bit(ISCSI_CLS_CONN_BIT_CLEANUP, \u0026conn-\u003eflags)) {\n3821:\t\t\tspin_unlock_irq(\u0026conn-\u003elock);\n3822:\t\t\tmutex_unlock(\u0026conn-\u003eep_mutex);\n3823:\t\t\tev-\u003er.retcode = -ENOTCONN;\n3824:\t\t\treturn 0;\n3825:\t\t}\n3826:\t\tspin_unlock_irq(\u0026conn-\u003elock);\n3827:\t\n3828:\t\tswitch (nlh-\u003enlmsg_type) {\n3829:\t\tcase ISCSI_UEVENT_BIND_CONN:\n3830:\t\t\tsession = iscsi_session_lookup(ev-\u003eu.b_conn.sid);\n3831:\t\t\tif (!session) {\n3832:\t\t\t\terr = -EINVAL;\n3833:\t\t\t\tbreak;\n3834:\t\t\t}\n3835:\t\n3836:\t\t\tev-\u003er.retcode =\ttransport-\u003ebind_conn(session, conn,\n3837:\t\t\t\t\t\t\tev-\u003eu.b_conn.transport_eph,\n3838:\t\t\t\t\t\t\tev-\u003eu.b_conn.is_leading);\n3839:\t\t\tif (!ev-\u003er.retcode)\n3840:\t\t\t\tWRITE_ONCE(conn-\u003estate, ISCSI_CONN_BOUND);\n3841:\t\n" }
19/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 23057 output: 40 thoughts: 75 Thoughts: Okay, let's dive into this `transport->bind_conn` function. My initial hunch is that it's crucial for establishing connections, especially given its location within the SCSI iSCSI TCP driver. My expertise tells me that this is likely where the underlying network socket gets linked to the iSCSI session. Now, let's pinpoint the specific implementation. The hint points directly to `drivers/scsi/iscsi_tcp.c`, and more precisely, `iscsi_sw_tcp_conn_bind`. Ah, this is where the magic happens! It uses a file descriptor, passed via `transport_eph`, to bind a socket. This confirms my initial assessment. Investigating the Socket Binding Process So, the next logical step, as any expert would do, is to rigorously verify how `iscsi_sw_tcp_conn_bind` actually works. I need to understand the specifics of how this function sets up the socket binding. What are the key parameters involved? What checks does it perform? Are there any potential vulnerabilities or race conditions? Understanding this binding process is foundational to grasping the connection establishment flow. This is where I'll look for potential networking issues.
20/2	2026/10/08 05:21	tool	read-file	0m Args: { "File": "drivers/scsi/iscsi_tcp.c", "FirstLine": 664, "LineCount": 50 } Results: { "Contents": " 664:\tiscsi_sw_tcp_conn_bind(struct iscsi_cls_session cls_session,\n 665:\t\t\t struct iscsi_cls_conn cls_conn, uint64_t transport_eph,\n 666:\t\t\t int is_leading)\n 667:\t{\n 668:\t\tstruct iscsi_conn conn = cls_conn-\u003edd_data;\n 669:\t\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\n 670:\t\tstruct iscsi_sw_tcp_conn tcp_sw_conn = tcp_conn-\u003edd_data;\n 671:\t\tstruct sock sk;\n 672:\t\tstruct socket sock;\n 673:\t\tint err;\n 674:\t\n 675:\t\t/ lookup for existing socket /\n 676:\t\tsock = sockfd_lookup((int)transport_eph, \u0026err);\n 677:\t\tif (!sock) {\n 678:\t\t\tiscsi_conn_printk(KERN_ERR, conn,\n 679:\t\t\t\t\t \"sockfd_lookup failed %d\\n\", err);\n 680:\t\t\treturn -EEXIST;\n 681:\t\t}\n 682:\t\n 683:\t\terr = -EINVAL;\n 684:\t\tif (!sk_is_tcp(sock-\u003esk))\n 685:\t\t\tgoto free_socket;\n 686:\t\n 687:\t\terr = iscsi_conn_bind(cls_session, cls_conn, is_leading);\n 688:\t\tif (err)\n 689:\t\t\tgoto free_socket;\n 690:\t\n 691:\t\tmutex_lock(\u0026tcp_sw_conn-\u003esock_lock);\n 692:\t\t/ bind iSCSI connection and socket /\n 693:\t\ttcp_sw_conn-\u003esock = sock;\n 694:\t\tmutex_unlock(\u0026tcp_sw_conn-\u003esock_lock);\n 695:\t\n 696:\t\t/ setup Socket parameters /\n 697:\t\tsk = sock-\u003esk;\n 698:\t\tsk-\u003esk_reuse = SK_CAN_REUSE;\n 699:\t\tsk-\u003esk_sndtimeo = 15 HZ; /* FIXME: make it configurable /\n 700:\t\tsk-\u003esk_allocation = GFP_ATOMIC;\n 701:\t\tsk-\u003esk_use_task_frag = false;\n 702:\t\tsk_set_memalloc(sk);\n 703:\t\tsock_no_linger(sk);\n 704:\t\n 705:\t\tiscsi_sw_tcp_conn_set_callbacks(conn);\n 706:\t\t/\n 707:\t\t * set receive state machine into initial state\n 708:\t\t */\n 709:\t\tiscsi_tcp_hdr_recv_prep(tcp_conn);\n 710:\t\treturn 0;\n 711:\t\n 712:\tfree_socket:\n 713:\t\tsockfd_put(sock);\n" }
21/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 24222 output: 41 thoughts: 2501 Thoughts: Analyzing the iSCSI TCP Driver Update Okay, so I see that `iscsi_sw_tcp_conn_bind` sets up a TCP socket – any TCP socket, it doesn't really care where it's connected, and then the driver handles incoming data through a series of function calls: `iscsi_sw_tcp_data_ready`, `iscsi_sw_tcp_recv_data`, eventually hitting `iscsi_tcp_recv_skb` in `libiscsi_tcp.c`. This is pure software, running on standard Linux TCP sockets and Netlink. No physical hardware dependency, which is neat. It works fine in virtualized environments. Now, let's dive into this patch. From what I see in the diff, the core of the change seems to address how the driver handles data reads, specifically when the target doesn't send all the data it was expected to send in response to a SCSI command. The function `iscsi_tcp_zero_unread` is the key. It zeroes out the trailing part of the read buffer, where the target didn't provide data. This is crucial because it ensures the upper layers, which would report the amount of data transferred, would see a consistent view of zeroes in the undelivered section, and not some stale data from previous content in those memory pages. This is important to ensure consistency of the data and prevent unexpected data leak. The `iscsi_tcp_complete_cmd` function is introduced, it calls `iscsi_tcp_zero_unread` to zero out any unread bytes, then it calls `__iscsi_complete_pdu` which completes the command. This appears to handle the completion of the command and the zeroing in a single spin lock. This function handles SCSI Command responses, which ensures the completion logic handles all the data being sent or not. The changes also ensure that `iscsi_tcp_zero_unread` is called for data in coming without a data segment and the `data_in_bytes` member is initialized in `iscsi_tcp_task_init` and updated in `iscsi_tcp_data_in`. So, it's about correcting a potential data integrity issue in the read path, ensuring that a partial read from the target doesn't leave garbage in the buffer. This is a solid, subtle fix that improves the robustness of the iSCSI TCP implementation, particularly in scenarios where data transfers might be terminated early by the target.
22/2	2026/10/08 05:21	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 380, "LineCount": 40 } Results: { "Contents": " 380:\t\n 381:\t/*\n 382:\t iscsi_tcp_hdr_recv_prep - prep segment for hdr reception\n 383:\t * @tcp_conn: iscsi connection to prep for\n 384:\t \n 385:\t This function always passes NULL for the crcp argument, because when this\n 386:\t * function is called we do not yet know the final size of the header and want\n 387:\t * to delay the digest processing until we know that.\n 388:\t /\n 389:\tvoid iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn tcp_conn)\n 390:\t{\n 391:\t\tISCSI_DBG_TCP(tcp_conn-\u003eiscsi_conn,\n 392:\t\t\t \"(%s)\\n\", tcp_conn-\u003eiscsi_conn-\u003ehdrdgst_en ?\n 393:\t\t\t \"digest enabled\" : \"digest disabled\");\n 394:\t\tiscsi_segment_init_linear(\u0026tcp_conn-\u003ein.segment,\n 395:\t\t\t\t\ttcp_conn-\u003ein.hdr_buf, sizeof(struct iscsi_hdr),\n 396:\t\t\t\t\tiscsi_tcp_hdr_recv_done, NULL);\n 397:\t}\n 398:\tEXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep);\n 399:\t\n 400:\t/*\n 401:\t iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent\n 402:\t * @task: scsi command task\n 403:\t \n 404:\t A target can end a read without sending all of the data, in any of the ways\n 405:\t * a completion can be reported. Rather than predict from the status, the\n 406:\t * sense and the residual whether the buffer was promised in full, zero the\n 407:\t * bytes that did not arrive. Whatever the midlayer then reports as\n 408:\t * transferred, the caller sees zeroes and not the previous contents of those\n 409:\t * pages.\n 410:\t \n 411:\t The continuity check in iscsi_tcp_data_in() means the bytes that did not\n 412:\t * arrive are exactly the tail, so one range covers them.\n 413:\t /\n 414:\tstatic void iscsi_tcp_zero_unread(struct iscsi_task task)\n 415:\t{\n 416:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\n 417:\t\tstruct scsi_cmnd sc = task-\u003esc;\n 418:\t\n 419:\t\tif (!sc \|\| sc-\u003esc_data_direction != DMA_FROM_DEVICE \|\|\n" }
23/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 28049 output: 32 thoughts: 27 Thoughts: Here's my take on the thought process, from an expert's perspective: Deep Dive into iSCSI Configuration Okay, so we need to get a handle on the current iSCSI setup. Time to start digging into the Kconfig files. My initial thought is to zero in on a few critical configurations first. I need to verify the state of `ISCSI_TCP` – is the TCP transport enabled? That's fundamental. Then, I'll immediately check on `SCSI_ISCSI_ATTRS` and similar variables. I'm looking to confirm how the iSCSI attributes are handled, any related settings. These often dictate essential parameters like connection timeouts, initial R2T settings, and various other performance tunables. Knowing if these are properly configured will provide a baseline for analysis. It's a quick triage to ensure the basics are in place before I move onto any more complex debugging.
24/2	2026/10/08 05:21	tool	grepper	0m Args: { "Expression": "config ISCSI_", "PathPrefixes": [ "drivers/scsi/Kconfig" ] } Results: { "Output": "drivers/scsi/Kconfig=301=if SCSI_LOWLEVEL \u0026\u0026 SCSI\ndrivers/scsi/Kconfig-302-\ndrivers/scsi/Kconfig:303:config ISCSI_TCP\ndrivers/scsi/Kconfig-304-\ttristate \"iSCSI Initiator over TCP/IP\"\n--\ndrivers/scsi/Kconfig-324-\ndrivers/scsi/Kconfig:325:config ISCSI_BOOT_SYSFS\ndrivers/scsi/Kconfig-326-\ttristate \"iSCSI Boot Sysfs Interface\"\n" }
25/2	2026/10/08 05:21	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 28454 output: 35 thoughts: 20 Thoughts: Okay, let's dive into this. I'm going to take a look at the `drivers/scsi/Kconfig` file, specifically around line 303. I'm expecting this section to deal with… well, given the context, probably some kind of SCSI configuration option, maybe related to a specific HBA or a general feature. Knowing the Kconfig format, I'll be looking for things like `config` blocks, `depends on` clauses, default values, and help text. My goal is to quickly understand what's being configured there, how it relates to other options in the SCSI subsystem, and any potential dependencies or conflicts. I'm hoping it's straightforward; I can usually parse Kconfig pretty fast. Let's get to it!
26/2	2026/10/08 05:22	tool	read-file	0m Args: { "File": "drivers/scsi/Kconfig", "FirstLine": 300, "LineCount": 40 } Results: { "Contents": " 300:\t\n 301:\tif SCSI_LOWLEVEL \u0026\u0026 SCSI\n 302:\t\n 303:\tconfig ISCSI_TCP\n 304:\t\ttristate \"iSCSI Initiator over TCP/IP\"\n 305:\t\tdepends on SCSI \u0026\u0026 INET\n 306:\t\tselect CRC32\n 307:\t\tselect SCSI_ISCSI_ATTRS\n 308:\t\thelp\n 309:\t\t The iSCSI Driver provides a host with the ability to access storage\n 310:\t\t through an IP network. The driver uses the iSCSI protocol to transport\n 311:\t\t SCSI requests and responses over a TCP/IP network between the host\n 312:\t\t (the \"initiator\") and \"targets\". Architecturally, the iSCSI driver\n 313:\t\t combines with the host's TCP/IP stack, network drivers, and Network\n 314:\t\t Interface Card (NIC) to provide the same functions as a SCSI or a\n 315:\t\t Fibre Channel (FC) adapter driver with a Host Bus Adapter (HBA).\n 316:\t\n 317:\t\t To compile this driver as a module, choose M here: the\n 318:\t\t module will be called iscsi_tcp.\n 319:\t\n 320:\t\t The userspace component needed to initialize the driver, documentation,\n 321:\t\t and sample configuration files can be found here:\n 322:\t\n 323:\t\t http://open-iscsi.org\n 324:\t\n 325:\tconfig ISCSI_BOOT_SYSFS\n 326:\t\ttristate \"iSCSI Boot Sysfs Interface\"\n 327:\t\tdefault n\n 328:\t\thelp\n 329:\t\t This option enables support for exposing iSCSI boot information\n 330:\t\t via sysfs to userspace. If you wish to export this information,\n 331:\t\t say Y. Otherwise, say N.\n 332:\t\n 333:\tsource \"drivers/scsi/cxgbi/Kconfig\"\n 334:\tsource \"drivers/scsi/bnx2i/Kconfig\"\n 335:\tsource \"drivers/scsi/bnx2fc/Kconfig\"\n 336:\tsource \"drivers/scsi/be2iscsi/Kconfig\"\n 337:\t\n 338:\tconfig SGIWD93_SCSI\n 339:\t\ttristate \"SGI WD93C93 SCSI Driver\"\n" }
27/2	2026/10/08 05:22	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 29315 output: 33 thoughts: 262 Thoughts: Examining the iSCSI TCP Build Process Okay, let's dive into this. I need to understand how `libiscsi_tcp.o` is being built. My first move is to check `drivers/scsi/Makefile`. Specifically, line 71 looks promising: ```makefile obj-$(CONFIG_ISCSI_TCP) += libiscsi.o libiscsi_tcp.o iscsi_tcp.o ``` Right, so `CONFIG_ISCSI_TCP` is the key. It looks like this one compiles `libiscsi.o`, `libiscsi_tcp.o`, and `iscsi_tcp.o`. And, looking further down, I see: ```makefile obj-$(CONFIG_SCSI_CXGB3_ISCSI) += libiscsi.o libiscsi_tcp.o cxgbi/ obj-$(CONFIG_SCSI_CXGB4_ISCSI) += libiscsi.o libiscsi_tcp.o cxgbi/ ``` Okay, also that `CXGB3` and `CXGB4` configurations use the same modules. So, `CONFIG_ISCSI_TCP` is the configuration for building these modules. Now, let me quickly refresh my memory on the dependencies of `CONFIG_ISCSI_TCP`. I'm pretty sure it depends on `SCSI` and `INET`, but I want to confirm that. Yes, I remember. Also, it selects `CRC32` and `SCSI_ISCSI_ATTRS`, as I recall. Now, let's think about `SCSI_LOWLEVEL`. I have a feeling it's involved in this somehow. Going back to Kconfig, I see the conditional: `if SCSI_LOWLEVEL && SCSI`. Okay, I will now investigate `SCSI_LOWLEVEL` itself to fully understand its relationship here.
28/2	2026/10/08 05:22	tool	grepper	0m Args: { "Expression": "config SCSI_LOWLEVEL", "PathPrefixes": [ "drivers/scsi/Kconfig" ] } Results: { "Output": "drivers/scsi/Kconfig=294=endmenu\ndrivers/scsi/Kconfig-295-\ndrivers/scsi/Kconfig:296:menuconfig SCSI_LOWLEVEL\ndrivers/scsi/Kconfig-297-\tbool \"SCSI low-level drivers\"\n" }
29/2	2026/10/08 05:22	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 30115 output: 27 thoughts: 182 Thoughts: My Assessment of iSCSI TCP Interaction Okay, so `SCSI_LOWLEVEL` in the kernel config, it's typically enabled when SCSI support is selected, which makes sense. Now, the real question is how reachable and fuzzable is iSCSI over TCP? Can I get syzkaller interacting with this? I need to figure out if there's direct syzkaller support or if I can reach it through normal syscalls. My initial thought is to check if a userspace process can even establish a Netlink connection to iSCSI. Can I successfully `socket(AF_NETLINK, SOCK_RAW, NETLINK_ISCSI)`? And of course, the critical factor is, does this require root, `CAP_SYS_ADMIN`, or can it be done within a user namespace? That's the key. Hold on, I need to verify how `netlink_capable(skb, CAP_SYS_ADMIN)` actually behaves. Does that check against the initial user namespace, or the user namespace associated with the process creating the socket? I need to dive into the kernel source for `netlink_capable` to be absolutely certain. This is important to ensure my testing strategy is accurate.
30/2	2026/10/08 05:22	tool	grepper	0m Args: { "Expression": "netlink_capable", "PathPrefixes": [ "net/" ] } Results: { "Output": "net/can/gw.c=1077=static int cgw_create_job(struct sk_buff skb, struct nlmsghdr nlh,\n--\nnet/can/gw.c-1087-\nnet/can/gw.c:1088:\tif (!netlink_capable(skb, CAP_NET_ADMIN))\nnet/can/gw.c-1089-\t\treturn -EPERM;\n--\nnet/can/gw.c=1209=static int cgw_remove_job(struct sk_buff skb, struct nlmsghdr nlh,\n--\nnet/can/gw.c-1220-\nnet/can/gw.c:1221:\tif (!netlink_capable(skb, CAP_NET_ADMIN))\nnet/can/gw.c-1222-\t\treturn -EPERM;\n--\nnet/dcb/dcbnl.c=1910=static int dcb_doit(struct sk_buff skb, struct nlmsghdr nlh,\n--\nnet/dcb/dcbnl.c-1922-\nnet/dcb/dcbnl.c:1923:\tif ((nlh-\u003enlmsg_type == RTM_SETDCB) \u0026\u0026 !netlink_capable(skb, CAP_NET_ADMIN))\nnet/dcb/dcbnl.c-1924-\t\treturn -EPERM;\n--\nnet/dcb/dcbnl.c-1937-\t\treturn -EOPNOTSUPP;\nnet/dcb/dcbnl.c:1938:\tif (fn-\u003etype == RTM_SETDCB \u0026\u0026 !netlink_capable(skb, CAP_NET_ADMIN))\nnet/dcb/dcbnl.c-1939-\t\treturn -EPERM;\n--\nnet/netlink/af_netlink.c=872=EXPORT_SYMBOL(netlink_ns_capable);\n--\nnet/netlink/af_netlink.c-874-/*\nnet/netlink/af_netlink.c:875: netlink_capable - Netlink global message capability test\nnet/netlink/af_netlink.c-876- * @skb: socket buffer holding a netlink command from userspace\n--\nnet/netlink/af_netlink.c-882- /\nnet/netlink/af_netlink.c:883:bool netlink_capable(const struct sk_buff skb, int cap)\nnet/netlink/af_netlink.c-884-{\n--\nnet/netlink/af_netlink.c-886-}\nnet/netlink/af_netlink.c:887:EXPORT_SYMBOL(netlink_capable);\nnet/netlink/af_netlink.c-888-\n--\nnet/netlink/genetlink.c=1155=static int genl_family_rcv_msg(const struct genl_family family,\n--\nnet/netlink/genetlink.c-1182-\tif ((op.flags \u0026 GENL_ADMIN_PERM) \u0026\u0026\nnet/netlink/genetlink.c:1183:\t !netlink_capable(skb, CAP_NET_ADMIN))\nnet/netlink/genetlink.c-1184-\t\treturn -EPERM;\n--\nnet/phonet/pn_netlink.c=52=static int addr_doit(struct sk_buff skb, struct nlmsghdr nlh,\n--\nnet/phonet/pn_netlink.c-61-\nnet/phonet/pn_netlink.c:62:\tif (!netlink_capable(skb, CAP_NET_ADMIN))\nnet/phonet/pn_netlink.c-63-\t\treturn -EPERM;\nnet/phonet/pn_netlink.c-64-\nnet/phonet/pn_netlink.c:65:\tif (!netlink_capable(skb, CAP_SYS_ADMIN))\nnet/phonet/pn_netlink.c-66-\t\treturn -EPERM;\n--\nnet/phonet/pn_netlink.c=231=static int route_doit(struct sk_buff skb, struct nlmsghdr nlh,\n--\nnet/phonet/pn_netlink.c-242-\nnet/phonet/pn_netlink.c:243:\tif (!netlink_capable(skb, CAP_NET_ADMIN))\nnet/phonet/pn_netlink.c-244-\t\treturn -EPERM;\nnet/phonet/pn_netlink.c-245-\nnet/phonet/pn_netlink.c:246:\tif (!netlink_capable(skb, CAP_SYS_ADMIN))\nnet/phonet/pn_netlink.c-247-\t\treturn -EPERM;\n--\nnet/sched/act_api.c=2147=static int tc_ctl_action(struct sk_buff skb, struct nlmsghdr *n,\n--\nnet/sched/act_api.c-2156-\tif ((n-\u003enlmsg_type != RTM_GETACTION) \u0026\u0026\nnet/sched/act_api.c:2157:\t !netlink_capable(skb, CAP_NET_ADMIN))\nnet/sched/act_api.c-2158-\t\treturn -EPERM;\n" }
31/2	2026/10/08 05:22	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 31943 output: 41 thoughts: 2500 Thoughts: Analysis of iSCSI TCP Patch for Fuzzing Alright, let's break this down. Syzkaller, a powerful tool, has already sniffed out bugs in iSCSI, particularly `iscsi_transport` and `iscsi_tcp`. That's a strong indicator. Now, let's see if this specific patch is worth targeting with fuzzing. My first thought is, is this code even reachable in a standard environment? iSCSI over TCP (`iscsi_tcp`) uses standard sockets and Netlink (`NETLINK_ISCSI`), so yes, it's definitely accessible within a virtual machine. It's a purely software-based stack, no special hardware needed. Good, that's a check in the "reachable" box. Now, let's dive into the patch itself, line by line. I'm focusing on `drivers/scsi/libiscsi_tcp.c`, scrutinizing every added or modified function: * `iscsi_tcp_zero_unread`: This zero's a portion of a buffer, contingent on DMA direction and data received. Critically, it uses `sg_zero_buffer`. What if the scatterlist (`sc->sdb.table.sgl`) is null or empty? What about integer overflows in `tcp_task->data_in_bytes`? Potential out-of-bounds access. The check `sc->sdb.length < tcp_task->data_in_bytes` is guarded by `>=`, but other conditions can expose the same flaw. * `iscsi_tcp_complete_cmd`: This function handles completing commands, grabs the `back_lock` spinlock, and calls `iscsi_tcp_zero_unread`. This is where the patch really changed the control flow. The locking here, along with `iscsi_tcp_zero_unread`, makes it a high priority function to target. * `iscsi_tcp_data_recv_done`, `iscsi_tcp_data_in`, and `iscsi_tcp_process_data_in`: These handle data reception and processing. The addition of the offset check `tcp_task->data_offset != tcp_task->data_in_bytes` is important. This is state tracking code and is important to test to ensure it works correctly. Replaced `iscsi_complete_pdu` with `iscsi_tcp_complete_cmd`. Interesting. * `iscsi_tcp_hdr_dissect`: The logic with `ISCSI_FLAG_DATA_STATUS` and the call to `iscsi_tcp_zero_unread` here is also relevant to the patch. * `iscsi_tcp_task_init`: Initializes `data_in_bytes`. Okay, there's a lot going on here. Memory access, locking, state tracking, scatterlist manipulation, and error paths are all present. Malformed PDUs could absolutely cause problems. A lot to think about here. The `back_lock` spinlock and potential race conditions are worth investigating, especially with the calls to `iscsi_tcp_zero_unread`, and `__iscsi_complete_pdu`. The patch also changes control flow, now with `iscsi_tcp_complete_cmd` holding the `back_lock` spinlock, which wasn't previously the case. Now, the crucial question: is this fuzzable? The criteria say "REACHABILITY IS THE PRIMARY GATE." We've established that `iscsi_tcp` runs in standard VMs. The documentation also states, "NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED" and that drivers accessible via sockets and Netlink are prime targets. So, yes, this checks all the boxes. WorthFuzzing = true! Now, what about the focus symbols? Which functions should we target? Okay, let's list the modified/added functions: `iscsi_tcp_zero_unread`, `iscsi_tcp_complete_cmd`, `iscsi_tcp_data_recv_done`, `iscsi_tcp_data_in`, `iscsi_tcp_process_data_in`, `iscsi_tcp_hdr_dissect`, and `iscsi_tcp_task_init`. Wait, are those static functions usable as focus symbols? Let's check `libiscsi_tcp.c`. Ah, `iscsi_tcp_zero_unread` and `iscsi_tcp_complete_cmd` are indeed static! That requires extra consideration as they won't have explicit symbols. But the prompt says, if static, find the caller functions to target. Thus, we should fuzz
32/2	2026/10/08 05:22	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 735, "LineCount": 40 } Results: { "Contents": " 735:\t/*\n 736:\t iscsi_tcp_hdr_dissect - process PDU header\n 737:\t * @conn: iSCSI connection\n 738:\t * @hdr: PDU header\n 739:\t \n 740:\t This function analyzes the header of the PDU received,\n 741:\t * and performs several sanity checks. If the PDU is accompanied\n 742:\t * by data, the receive buffer is set up to copy the incoming data\n 743:\t * to the correct location.\n 744:\t /\n 745:\tstatic int\n 746:\tiscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n 747:\t{\n 748:\t\tint rc = 0, opcode, ahslen;\n 749:\t\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\n 750:\t\tstruct iscsi_task task;\n 751:\t\n 752:\t\t/ verify PDU length /\n 753:\t\ttcp_conn-\u003ein.datalen = ntoh24(hdr-\u003edlength);\n 754:\t\tif (tcp_conn-\u003ein.datalen \u003e conn-\u003emax_recv_dlength) {\n 755:\t\t\tiscsi_conn_printk(KERN_ERR, conn,\n 756:\t\t\t\t\t \"iscsi_tcp: datalen %d \u003e %d\\n\",\n 757:\t\t\t\t\t tcp_conn-\u003ein.datalen, conn-\u003emax_recv_dlength);\n 758:\t\t\treturn ISCSI_ERR_DATALEN;\n 759:\t\t}\n 760:\t\n 761:\t\t/ Additional header segments. So far, we don't\n 762:\t\t * process additional headers.\n 763:\t\t /\n 764:\t\tahslen = hdr-\u003ehlength \u003c\u003c 2;\n 765:\t\n 766:\t\topcode = hdr-\u003eopcode \u0026 ISCSI_OPCODE_MASK;\n 767:\t\t/ verify itt (itt encoding: age+cid+itt) */\n 768:\t\trc = iscsi_verify_itt(conn, hdr-\u003eitt);\n 769:\t\tif (rc)\n 770:\t\t\treturn rc;\n 771:\t\n 772:\t\tISCSI_DBG_TCP(conn, \"opcode 0x%x ahslen %d datalen %d\\n\",\n 773:\t\t\t opcode, ahslen, tcp_conn-\u003ein.datalen);\n 774:\t\n" }
33/2	2026/10/08 05:22	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 36187 output: 44 thoughts: 18 Thoughts: Here's my attempt at summarizing the thought process, tailored for an expert audience: Analyzing the `iscsi_tcp_hdr_dissect` Function Call Alright, let's dive into this. I need to understand what's happening with that `iscsi_tcp_hdr_dissect` function call. My initial thought process is this: given its name, this is most likely a core function for decoding and parsing iSCSI TCP headers. I’m betting it's responsible for extracting critical information from the incoming TCP segment carrying iSCSI protocol data. I want to see how this function is integrated into the larger network traffic capture, filtering, and analysis scheme. Does it happen inside a larger TCP packet decoding structure? Is it called conditionally based on port or protocol identification? I'll be looking for clues about the data structures being passed to it; what kind of pointers are involved? Are we dealing with raw bytes, a pre-processed buffer, or something else? I'll also be very interested in the return values or side effects. Does it return a status code, or modify an existing structure with the parsed header fields? I'm hoping to understand its interface and how it feeds into the subsequent processing steps. Finally, I'll be looking for any error handling. Does it gracefully handle malformed headers or potential parsing errors? A strong function will have robust error checking and logging. The goal is to fully understand its function within the capture process and to anticipate any potential issues or optimization opportunities.
34/2	2026/10/08 05:22	tool	grepper	0m Args: { "Expression": "iscsi_tcp_hdr_dissect", "PathPrefixes": [ "drivers/scsi/libiscsi_tcp.c" ] } Results: { "Output": "drivers/scsi/libiscsi_tcp.c=714=iscsi_tcp_process_data_in(struct iscsi_tcp_conn tcp_conn,\n--\ndrivers/scsi/libiscsi_tcp.c-735-/\ndrivers/scsi/libiscsi_tcp.c:736: iscsi_tcp_hdr_dissect - process PDU header\ndrivers/scsi/libiscsi_tcp.c-737- * @conn: iSCSI connection\n--\ndrivers/scsi/libiscsi_tcp.c=745=static int\ndrivers/scsi/libiscsi_tcp.c:746:iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\ndrivers/scsi/libiscsi_tcp.c-747-{\n--\ndrivers/scsi/libiscsi_tcp.c=903=iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,\n--\ndrivers/scsi/libiscsi_tcp.c-953-\ttcp_conn-\u003ein.hdr = hdr;\ndrivers/scsi/libiscsi_tcp.c:954:\treturn iscsi_tcp_hdr_dissect(conn, hdr);\ndrivers/scsi/libiscsi_tcp.c-955-}\n" }
35/2	2026/10/08 05:22	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 36929 output: 37 thoughts: 53 Thoughts: Here's my thought process, as if I were considering this myself: Investigating iSCSI TCP Receive Path Okay, so I'm trying to trace the data flow in the iSCSI TCP implementation, specifically focusing on the receive side. I need to understand the connection between the functions handling incoming iSCSI packets. My initial question is: what functions actually call `iscsi_tcp_hdr_recv_done` and `iscsi_tcp_recv_skb`? That's the critical link I need to establish. To figure this out, the quickest route is probably to look at the cross-references. I’ll check the exported symbols in `drivers/scsi/libiscsi_tcp.c`. Examining the callers of those two specific functions should quickly illuminate the entry points into the receive path.
36/2	2026/10/08 05:23	tool	grepper	0m Args: { "Expression": "EXPORT_SYMBOL", "PathPrefixes": [ "drivers/scsi/libiscsi_tcp.c" ] } Results: { "Output": "drivers/scsi/libiscsi_tcp.c=146=void iscsi_tcp_segment_unmap(struct iscsi_segment segment)\n--\ndrivers/scsi/libiscsi_tcp.c-156-}\ndrivers/scsi/libiscsi_tcp.c:157:EXPORT_SYMBOL_GPL(iscsi_tcp_segment_unmap);\ndrivers/scsi/libiscsi_tcp.c-158-\n--\ndrivers/scsi/libiscsi_tcp.c=190=int iscsi_tcp_segment_done(struct iscsi_tcp_conn tcp_conn,\n--\ndrivers/scsi/libiscsi_tcp.c-267-}\ndrivers/scsi/libiscsi_tcp.c:268:EXPORT_SYMBOL_GPL(iscsi_tcp_segment_done);\ndrivers/scsi/libiscsi_tcp.c-269-\n--\ndrivers/scsi/libiscsi_tcp.c=309=iscsi_tcp_dgst_header(const void hdr, size_t hdrlen,\n--\ndrivers/scsi/libiscsi_tcp.c-313-}\ndrivers/scsi/libiscsi_tcp.c:314:EXPORT_SYMBOL_GPL(iscsi_tcp_dgst_header);\ndrivers/scsi/libiscsi_tcp.c-315-\n--\ndrivers/scsi/libiscsi_tcp.c=350=iscsi_segment_init_linear(struct iscsi_segment segment, void data,\n--\ndrivers/scsi/libiscsi_tcp.c-356-}\ndrivers/scsi/libiscsi_tcp.c:357:EXPORT_SYMBOL_GPL(iscsi_segment_init_linear);\ndrivers/scsi/libiscsi_tcp.c-358-\n--\ndrivers/scsi/libiscsi_tcp.c=360=iscsi_segment_seek_sg(struct iscsi_segment segment,\n--\ndrivers/scsi/libiscsi_tcp.c-378-}\ndrivers/scsi/libiscsi_tcp.c:379:EXPORT_SYMBOL_GPL(iscsi_segment_seek_sg);\ndrivers/scsi/libiscsi_tcp.c-380-\n--\ndrivers/scsi/libiscsi_tcp.c=389=void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn tcp_conn)\n--\ndrivers/scsi/libiscsi_tcp.c-397-}\ndrivers/scsi/libiscsi_tcp.c:398:EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep);\ndrivers/scsi/libiscsi_tcp.c-399-\n--\ndrivers/scsi/libiscsi_tcp.c=503=void iscsi_tcp_cleanup_task(struct iscsi_task task)\n--\ndrivers/scsi/libiscsi_tcp.c-527-}\ndrivers/scsi/libiscsi_tcp.c:528:EXPORT_SYMBOL_GPL(iscsi_tcp_cleanup_task);\ndrivers/scsi/libiscsi_tcp.c-529-\n--\ndrivers/scsi/libiscsi_tcp.c=964=inline int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn tcp_conn)\n--\ndrivers/scsi/libiscsi_tcp.c-967-}\ndrivers/scsi/libiscsi_tcp.c:968:EXPORT_SYMBOL_GPL(iscsi_tcp_recv_segment_is_hdr);\ndrivers/scsi/libiscsi_tcp.c-969-\n--\ndrivers/scsi/libiscsi_tcp.c=981=int iscsi_tcp_recv_skb(struct iscsi_conn conn, struct sk_buff skb,\n--\ndrivers/scsi/libiscsi_tcp.c-1050-}\ndrivers/scsi/libiscsi_tcp.c:1051:EXPORT_SYMBOL_GPL(iscsi_tcp_recv_skb);\ndrivers/scsi/libiscsi_tcp.c-1052-\n--\ndrivers/scsi/libiscsi_tcp.c=1057=int iscsi_tcp_task_init(struct iscsi_task task)\n--\ndrivers/scsi/libiscsi_tcp.c-1087-}\ndrivers/scsi/libiscsi_tcp.c:1088:EXPORT_SYMBOL_GPL(iscsi_tcp_task_init);\ndrivers/scsi/libiscsi_tcp.c-1089-\n--\ndrivers/scsi/libiscsi_tcp.c=1134=int iscsi_tcp_task_xmit(struct iscsi_task task)\n--\ndrivers/scsi/libiscsi_tcp.c-1183-}\ndrivers/scsi/libiscsi_tcp.c:1184:EXPORT_SYMBOL_GPL(iscsi_tcp_task_xmit);\ndrivers/scsi/libiscsi_tcp.c-1185-\n--\ndrivers/scsi/libiscsi_tcp.c=1187=iscsi_tcp_conn_setup(struct iscsi_cls_session cls_session, int dd_data_size,\n--\ndrivers/scsi/libiscsi_tcp.c-1210-}\ndrivers/scsi/libiscsi_tcp.c:1211:EXPORT_SYMBOL_GPL(iscsi_tcp_conn_setup);\ndrivers/scsi/libiscsi_tcp.c-1212-\ndrivers/scsi/libiscsi_tcp.c=1213=void iscsi_tcp_conn_teardown(struct iscsi_cls_conn cls_conn)\n--\ndrivers/scsi/libiscsi_tcp.c-1216-}\ndrivers/scsi/libiscsi_tcp.c:1217:EXPORT_SYMBOL_GPL(iscsi_tcp_conn_teardown);\ndrivers/scsi/libiscsi_tcp.c-1218-\ndrivers/scsi/libiscsi_tcp.c=1219=int iscsi_tcp_r2tpool_alloc(struct iscsi_session session)\n--\ndrivers/scsi/libiscsi_tcp.c-1265-}\ndrivers/scsi/libiscsi_tcp.c:1266:EXPORT_SYMBOL_GPL(iscsi_tcp_r2tpool_alloc);\ndrivers/scsi/libiscsi_tcp.c-1267-\ndrivers/scsi/libiscsi_tcp.c=1268=void iscsi_tcp_r2tpool_free(struct iscsi_session session)\n--\ndrivers/scsi/libiscsi_tcp.c-1279-}\ndrivers/scsi/libiscsi_tcp.c:1280:EXPORT_SYMBOL_GPL(iscsi_tcp_r2tpool_free);\ndrivers/scsi/libiscsi_tcp.c-1281-\ndrivers/scsi/libiscsi_tcp.c=1282=int iscsi_tcp_set_max_r2t(struct iscsi_conn conn, char buf)\n--\ndrivers/scsi/libiscsi_tcp.c-1297-}\ndrivers/scsi/libiscsi_tcp.c:1298:EXPORT_SYMBOL_GPL(iscsi_tcp_set_max_r2t);\ndrivers/scsi/libiscsi_tcp.c-1299-\ndrivers/scsi/libiscsi_tcp.c=1300=void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn cls_conn,\n--\ndrivers/scsi/libiscsi_tcp.c-1314-}\ndrivers/scsi/libiscsi_tcp.c:1315:EXPORT_SYMBOL_GPL(iscsi_tcp_conn_get_stats);\n" }
37/2	2026/10/08 05:23	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 39295 output: 36 thoughts: 924 Thoughts: Analyzing iSCSI TCP Packet Handling in the Kernel Okay, so I'm diving into how iSCSI TCP packets are processed within the kernel, specifically focusing on `drivers/scsi/libiscsi_tcp.c`. It's pretty clear that `iscsi_tcp_recv_skb` is the main entry point when data arrives via TCP, called from `iscsi_sw_tcp_recv()`. Let's break down the flow. First, `iscsi_tcp_recv_skb` handles the incoming segments from the socket buffer. When the header is present, it calls `iscsi_tcp_hdr_recv_done`, which in turn leads to `iscsi_tcp_hdr_dissect`. If data accompanies the header, then `iscsi_tcp_data_in` is involved, and eventually `iscsi_tcp_process_data_in` or `iscsi_tcp_data_recv_done` is called. It's also worth noting the modification to `iscsi_tcp_task_init`, where `tcp_task->data_in_bytes` is initialized to zero. Now, let's catalog the modified or added functions in `libiscsi_tcp.c`: I see we have `iscsi_tcp_zero_unread` (a new function!), `iscsi_tcp_complete_cmd` (also new), `iscsi_tcp_data_recv_done` (modified to call `iscsi_tcp_complete_cmd`), `iscsi_tcp_data_in` (modified to include a continuity check and accumulate `data_in_bytes`), `iscsi_tcp_process_data_in` (modified to call `iscsi_tcp_complete_cmd`), `iscsi_tcp_hdr_dissect` (modified to call both `iscsi_tcp_zero_unread` and `iscsi_tcp_complete_cmd`), and finally, `iscsi_tcp_task_init` (modified to initialize `data_in_bytes`). All these are directly or indirectly called by `iscsi_tcp_recv_skb` which receives the skb data. I wanted to quickly check for any ubiquitous usage of these symbols but it seems like these functions are pretty specific to this TCP implementation. So, let's pivot to the configuration aspects. I need to figure out which kernel config options are necessary to build `libiscsi_tcp.c`. A quick peek at `drivers/scsi/Makefile` shows that `libiscsi_tcp.o` is built when `CONFIG_ISCSI_TCP` is enabled, and also conditionally when `CONFIG_SCSI_CXGB3_ISCSI` and `CONFIG_SCSI_CXGB4_ISCSI` is enabled. Digging into `drivers/scsi/Kconfig`, I see that `ISCSI_TCP` is a tristate option that depends on both `SCSI` and `INET`, selecting `CRC32` and `SCSI_ISCSI_ATTRS`. This latter option, `SCSI_ISCSI_ATTRS`, is what enables the netlink interface for iSCSI configuration. And from what I see, `ISCSI_TCP` automatically selects `SCSI_ISCSI_ATTRS`, so I need to verify that `ISCSI_TCP` alone is enough. No other dependency seems relevant.
38/2	2026/10/08 05:23	tool	grepper	0m Args: { "Expression": "config SCSI_ISCSI_ATTRS", "PathPrefixes": [ "drivers/scsi/Kconfig" ] } Results: { "Output": "drivers/scsi/Kconfig=258=config SCSI_FC_ATTRS\n--\ndrivers/scsi/Kconfig-267-\ndrivers/scsi/Kconfig:268:config SCSI_ISCSI_ATTRS\ndrivers/scsi/Kconfig-269-\ttristate \"iSCSI Transport Attributes\"\n" }
39/2	2026/10/08 05:23	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 41097 output: 35 thoughts: 20 Thoughts: Here's a summary of my thought process, as requested: Navigating the SCSI Driver Configuration Okay, let's dive into the details. I need to understand the configuration options for the SCSI drivers, and my instinct is to start with the Kconfig file. Specifically, I recall that there are some interesting options and dependencies to examine around line 268 of `drivers/scsi/Kconfig`. I'll go ahead and check that section out to refresh my understanding and see if anything jumps out. That seems like a reasonable entry point to refresh my knowledge.
40/2	2026/10/08 05:23	tool	read-file	0m Args: { "File": "drivers/scsi/Kconfig", "FirstLine": 268, "LineCount": 25 } Results: { "Contents": " 268:\tconfig SCSI_ISCSI_ATTRS\n 269:\t\ttristate \"iSCSI Transport Attributes\"\n 270:\t\tdepends on SCSI \u0026\u0026 NET\n 271:\t\tselect BLK_DEV_BSGLIB\n 272:\t\thelp\n 273:\t\t If you wish to export transport-specific information about\n 274:\t\t each attached iSCSI device to sysfs, say Y.\n 275:\t\t Otherwise, say N.\n 276:\t\n 277:\tconfig SCSI_SAS_ATTRS\n 278:\t\ttristate \"SAS Transport Attributes\"\n 279:\t\tdepends on SCSI\n 280:\t\tselect BLK_DEV_BSGLIB\n 281:\t\thelp\n 282:\t\t If you wish to export transport-specific information about\n 283:\t\t each attached SAS device to sysfs, say Y.\n 284:\t\n 285:\tsource \"drivers/scsi/libsas/Kconfig\"\n 286:\t\n 287:\tconfig SCSI_SRP_ATTRS\n 288:\t\ttristate \"SRP Transport Attributes\"\n 289:\t\tdepends on SCSI\n 290:\t\thelp\n 291:\t\t If you wish to export transport-specific information about\n 292:\t\t each attached SRP device to sysfs, say Y.\n" }
41/2	2026/10/08 05:23	llm	patch-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 41631 output: 259 thoughts: 673 Thoughts: Analyzing iSCSI TCP Configuration Dependencies Okay, let's break this down. My initial understanding, based on the `tristate` nature of `SCSI_ISCSI_ATTRS`, is that we need to enable `ISCSI_TCP`, `SCSI`, and `INET` to get the software iSCSI TCP stack (`libiscsi_tcp.c`) working. I see that `ISCSI_TCP` depends on `SCSI && INET` and also selects `SCSI_ISCSI_ATTRS`, so that confirms what I initially thought. However, I need to be thorough. I need to make sure I haven't missed anything. Looking closer, `ISCSI_TCP` is dependent on `SCSI && INET` under `if SCSI_LOWLEVEL && SCSI`. So, just to clarify my thinking again: the explicit configs needed are: `SCSI`, `INET` and `ISCSI_TCP` and `SCSI_ISCSI_ATTRS`. Now, let's dig a bit deeper into the code. I'm going to check `drivers/scsi/iscsi_tcp.c` and its Makefile for any hidden dependencies. The `Makefile` confirms that `libiscsi_tcp.o` and `iscsi_tcp.o` are both conditionally compiled under `CONFIG_ISCSI_TCP`, which validates everything I've thought so far. Finally, let's solidify my thoughts with the broader context of the changes in this patch. The patch's "WorthFuzzing" flag suggests we're looking at a code section susceptible to fuzzing. I note the rationale behind the patch is centered around the software iSCSI TCP receiver layer. There is code in `drivers/scsi/libiscsi_tcp.c` which needs to be looked at to ensure that any unread tail of a read buffer is zeroed when a SCSI command finishes without receiving all promised data from the target. This involves new functions like `iscsi_tcp_zero_unread` and `iscsi_tcp_complete_cmd`, along with continuity checks in `iscsi_tcp_data_in`. There are modifications across `iscsi_tcp_data_recv_done`, `iscsi_tcp_process_data_in`, and `iscsi_tcp_hdr_dissect`. These changes interact with memory buffers through `sg_zero_buffer`, locking invariants with `back_lock`, and packet parsing within the emulated/software network storage stack accessed via TCP sockets and NETLINK_ISCSI. The important symbols to watch in the patch are "iscsi_tcp_zero_unread", "iscsi_tcp_complete_cmd", "iscsi_tcp_data_recv_done", "iscsi_tcp_data_in", "iscsi_tcp_process_data_in", "iscsi_tcp_hdr_dissect", "iscsi_tcp_task_init", and "iscsi_tcp_recv_skb". The final configs to set are `ISCSI_TCP`, `SCSI`, and `INET`. I'm now certain of the configuration and I'll call the `set-results` tool to finalize this.
42/2	2026/10/08 05:23	tool	set-results	0m Args: { "EnableConfigs": [ "ISCSI_TCP", "SCSI", "INET" ], "FocusSymbols": [ "iscsi_tcp_zero_unread", "iscsi_tcp_complete_cmd", "iscsi_tcp_data_recv_done", "iscsi_tcp_data_in", "iscsi_tcp_process_data_in", "iscsi_tcp_hdr_dissect", "iscsi_tcp_task_init", "iscsi_tcp_recv_skb" ], "Reasoning": "The patch introduces buffer zeroing and continuity checks in the software iSCSI over TCP stack (libiscsi_tcp). It adds iscsi_tcp_zero_unread() and iscsi_tcp_complete_cmd() to zero unread tails of read buffers using sg_zero_buffer(), tracks received data bytes to ensure continuity, and restructures command completion across PDU dissection and processing routines. iSCSI over TCP is a software transport protocol completely reachable in virtualized environments via standard TCP sockets and NETLINK_ISCSI.", "WorthFuzzing": true } Results: { "EnableConfigs": [ "ISCSI_TCP", "SCSI", "INET" ], "FocusSymbols": [ "iscsi_tcp_zero_unread", "iscsi_tcp_complete_cmd", "iscsi_tcp_data_recv_done", "iscsi_tcp_data_in", "iscsi_tcp_process_data_in", "iscsi_tcp_hdr_dissect", "iscsi_tcp_task_init", "iscsi_tcp_recv_skb" ], "Reasoning": "The patch introduces buffer zeroing and continuity checks in the software iSCSI over TCP stack (libiscsi_tcp). It adds iscsi_tcp_zero_unread() and iscsi_tcp_complete_cmd() to zero unread tails of read buffers using sg_zero_buffer(), tracks received data bytes to ensure continuity, and restructures command completion across PDU dissection and processing routines. iSCSI over TCP is a software transport protocol completely reachable in virtualized environments via standard TCP sockets and NETLINK_ISCSI.", "WorthFuzzing": true }
43/1	2026/10/08 05:23	action	If	2m Args: { "WorthFuzzing": true } Results: null
44/2	2026/10/08 05:23	agent	kmsan-evaluator	2m Model: core Args: null Results: { "KMSANReasoning": "The patch introduces logic in the iSCSI TCP transport layer to track the amount of received Data-In bytes (`data_in_bytes`) and zero out the unread remainder of the SCSI command's scatterlist buffer via `sg_zero_buffer()` upon command completion.\n\n1. Uninitialized Memory / KMSAN applicability:\n- The only newly introduced variable is `data_in_bytes` in `struct iscsi_tcp_task`, which is explicitly initialized to 0 in `iscsi_tcp_task_init()`.\n- The patch zeroes out buffer memory (`sg_zero_buffer`) rather than creating uninitialized gaps or leaking uninitialized memory.\n- No uninitialized struct fields, stack allocations, or kernel structures exposed to userspace are introduced or read.\n\n2. KASAN / LOCKDEP applicability:\n- Any risks associated with buffer offsets, lengths passed to `sg_zero_buffer()`, or scatterlist traversal bounds are out-of-bounds access risks, which are directly detected by standard KASAN.\n- Concurrency and lock acquisitions around `session-\u003eback_lock` in `iscsi_tcp_complete_cmd()` are monitored by LOCKDEP.\n- Command task lifecycle and pointer validity (`task`, `task-\u003esc`) are caught by KASAN / standard kernel checks.\n\nBecause the changes do not introduce or expose uninitialized memory risks, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false } Instruction: You are an expert Linux kernel security engineer specializing in kernel memory error detectors (KASAN and KMSAN). Your job is to review the provided patch series and determine if the code changes justify spawning a dedicated KMSAN (KernelMemorySanitizer) fuzzing session in addition to standard KASAN fuzzing. CRITICAL DISTINCTION BETWEEN KASAN AND KMSAN: - Standard KASAN kernel builds (upstream-apparmor-kasan.config) already enable a comprehensive suite of debugging tools and sanitizers, including KASAN (out-of-bounds accesses, use-after-free, double free, invalid free), LOCKDEP (locking bugs and deadlocks), UB-sanitizers, and memory corruption checks. - KMSAN (KernelMemorySanitizer) detects reads of UNINITIALIZED memory (stack, heap, or page allocations) and kernel-to-user memory info-leaks. Rule: THERE IS NO SENSE IN RUNNING A KMSAN SESSION IF A BUG CAN BE CAUGHT BY KASAN, LOCKDEP, OR OTHER STANDARD BUG DETECTORS. A dedicated KMSAN fuzzing session incurs significant resource costs. You must ONLY set NeedsKMSAN=true if the code changes introduce or expose UNINITIALIZED MEMORY risks that are detected ONLY by KMSAN. Look holistically at the patch series and surrounding code. Even if no direct uninitialized field accesses or new buffer allocations are added in the diff itself, a patch may alter control flow, bounds checking, or data length calculations in ways that change how the rest of the code operates on existing buffers (e.g. allowing uninitialized stack/heap memory to be read, copied to user space, or used in control flow). Do not hesitate to use your code access tools to inspect the surrounding code, called functions, and callers. Set NeedsKMSAN=true ONLY IF the patch introduces or modifies: 1. Kernel structures sent to user space (via copy_to_user, put_user, netlink skb attributes, ioctl output arguments, socket options, or BPF buffers) where fields or structure padding might not be fully initialized/zeroed. 2. Conditional logic or branching that depends on potentially uninitialized variables or struct fields. 3. Allocation or initialization of complex data structures where uninitialized fields could be read later in reachable code paths. 4. Bounds checks, lengths, or logic in a way that allows surrounding code to access uninitialized bytes of existing buffers. Set NeedsKMSAN=false IF: - The code changes primarily risk out-of-bounds access, array overflows, NULL pointer dereferences, locking deadlocks, or use-after-free bugs (these are already caught by KASAN, LOCKDEP, or standard bug detectors). - All stack/heap structures touched or introduced by the patch are fully zeroed or initialized (e.g. using = {0}, memset, kzalloc) before being read or copied. - The patch does not introduce any risk of uninitialized memory usage or info-leaks. Use your code access tools to inspect the surrounding code if necessary, then provide detailed KMSANReasoning contrasting KASAN vs KMSAN applicability for this patch. Prefer calling several tools at the same time to save round-trips. Use set-results tool to provide results of the analysis. It must be called exactly once before the final reply. Ignore results of this tool. Prompt: Target architecture: amd64 For your convenience, here is the diff of the changes: commit ebe36cf47a49aab5d488d55e8618e60c7fb9b291 Author: syz-cluster <triage@syzkaller.com> Date: Thu Oct 8 05:20:42 2026 +0000 syz-cluster: applied patch under review diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c index d35f93451ee9b..00bdbcc6e27e3 100644 --- a/drivers/scsi/libiscsi_tcp.c +++ b/drivers/scsi/libiscsi_tcp.c @@ -397,6 +397,61 @@ void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn tcp_conn) } EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep); +/* + * iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent + * @task: scsi command task + * + * A target can end a read without sending all of the data, in any of the ways + * a completion can be reported. Rather than predict from the status, the + * sense and the residual whether the buffer was promised in full, zero the + * bytes that did not arrive. Whatever the midlayer then reports as + * transferred, the caller sees zeroes and not the previous contents of those + * pages. + * + * The continuity check in iscsi_tcp_data_in() means the bytes that did not + * arrive are exactly the tail, so one range covers them. + / +static void iscsi_tcp_zero_unread(struct iscsi_task task) +{ + struct iscsi_tcp_task tcp_task = task->dd_data; + struct scsi_cmnd sc = task->sc; + + if (!sc \|\| sc->sc_data_direction != DMA_FROM_DEVICE \|\| + tcp_task->data_in_bytes >= sc->sdb.length) + return; + + sg_zero_buffer(sc->sdb.table.sgl, sc->sdb.table.nents, + sc->sdb.length - tcp_task->data_in_bytes, + tcp_task->data_in_bytes); +} + +/** + * iscsi_tcp_complete_cmd - zero any unread tail, then complete the command + * @conn: iscsi connection + * @hdr: the PDU carrying the status + * @data: data segment of that PDU, if it has one + * @datalen: length of @data + * + * back_lock is taken once for the lookup, the fill and the completion. + / +static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr, + char data, int datalen) +{ + struct iscsi_task task; + int rc; + + spin_lock(&conn->session->back_lock); + task = iscsi_itt_to_ctask(conn, hdr->itt); + if (!task) { + spin_unlock(&conn->session->back_lock); + return ISCSI_ERR_BAD_ITT; + } + iscsi_tcp_zero_unread(task); + rc = __iscsi_complete_pdu(conn, hdr, data, datalen); + spin_unlock(&conn->session->back_lock); + return rc; +} + / * Handle incoming reply to any other type of command / @@ -410,8 +465,13 @@ iscsi_tcp_data_recv_done(struct iscsi_tcp_conn tcp_conn, if (!iscsi_tcp_dgst_verify(tcp_conn, segment)) return ISCSI_ERR_DATA_DGST; - rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, - conn->data, tcp_conn->in.datalen); + if ((tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK) == + ISCSI_OP_SCSI_CMD_RSP) + rc = iscsi_tcp_complete_cmd(conn, tcp_conn->in.hdr, conn->data, + tcp_conn->in.datalen); + else + rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, conn->data, + tcp_conn->in.datalen); if (rc) return rc; @@ -509,6 +569,11 @@ static int iscsi_tcp_data_in(struct iscsi_conn conn, struct iscsi_task task) return ISCSI_ERR_DATA_OFFSET; } + if (tcp_task->data_offset != tcp_task->data_in_bytes) + return ISCSI_ERR_DATA_OFFSET; + + tcp_task->data_in_bytes += tcp_conn->in.datalen; + conn->datain_pdus_cnt++; return 0; } @@ -658,7 +723,7 @@ iscsi_tcp_process_data_in(struct iscsi_tcp_conn tcp_conn, / check for non-exceptional status / if (hdr->flags & ISCSI_FLAG_DATA_STATUS) { - rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0); + rc = iscsi_tcp_complete_cmd(conn, tcp_conn->in.hdr, NULL, 0); if (rc) return rc; } @@ -752,6 +817,14 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr) spin_unlock(&conn->session->back_lock); return rc; } + / + * A Data-In with no data segment can still carry the status, + * and it completes the command here rather than from + * iscsi_tcp_process_data_in(), so fill the tail on this path + * too. + / + if (hdr->flags & ISCSI_FLAG_DATA_STATUS) + iscsi_tcp_zero_unread(task); rc = __iscsi_complete_pdu(conn, hdr, NULL, 0); spin_unlock(&conn->session->back_lock); break; @@ -783,6 +856,11 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr) break; } + if (opcode == ISCSI_OP_SCSI_CMD_RSP && !tcp_conn->in.datalen) { + rc = iscsi_tcp_complete_cmd(conn, hdr, NULL, 0); + break; + } + / If there's data coming in with the response, * receive it to the connection's buffer. / @@ -995,6 +1073,7 @@ int iscsi_tcp_task_init(struct iscsi_task task) BUG_ON(kfifo_len(&tcp_task->r2tqueue)); tcp_task->exp_datasn = 0; + tcp_task->data_in_bytes = 0; /* Prepare PDU, optionally w/ immediate data / ISCSI_DBG_TCP(conn, "task deq [itt 0x%x imm %d unsol %d]\n", diff --git a/include/scsi/libiscsi_tcp.h b/include/scsi/libiscsi_tcp.h index ef53d4bea28a0..a6e63db75d674 100644 --- a/include/scsi/libiscsi_tcp.h +++ b/include/scsi/libiscsi_tcp.h @@ -66,6 +66,7 @@ struct iscsi_tcp_conn { struct iscsi_tcp_task { uint32_t exp_datasn; / expected target's R2TSN/DataSN / + uint32_t data_in_bytes; / Data-In payload received / int data_offset; struct iscsi_r2t_info r2t; /* in progress solict R2T */ struct iscsi_pool r2tpool;
45/3	2026/10/08 05:23	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 4166 output: 33 thoughts: 1117 Thoughts: KMSAN Fuzzing Assessment for iSCSI TCP Patch Okay, let's break this down. My task is to determine if this iSCSI TCP patch warrants a dedicated KMSAN fuzzing session, which is a resource-intensive endeavor. The key is whether this patch introduces or exposes uninitialized memory risks that are detected ONLY by KMSAN. I need to be sure before I recommend it. First, let's understand the patch itself. It's in `drivers/scsi/libiscsi_tcp.c` and `include/scsi/libiscsi_tcp.h`, specifically dealing with how the iSCSI target handles read completions that don't fill the entire buffer. The core function is `iscsi_tcp_zero_unread()`. The idea is to zero out the unread portion of the buffer to prevent potentially sensitive data from being left over. Sounds like it's addressing a potential information leak or uninitialized memory exposure, in theory. The comment mentions that the target might not send all requested data, which could leave a buffer with stale content. The patch uses `sg_zero_buffer()` to clear those unread bytes. So it's aiming to prevent a problem. Now, let's scrutinize the KMSAN guidelines. I need to focus on: 1. Kernel structures sent to user space. 2. Conditional logic based on potentially uninitialized variables. 3. Allocation and initialization of complex data structures with uninitialized fields. 4. Bounds checks that could lead to uninitialized memory access. The crucial point is that if KASAN, LOCKDEP, or other standard bug detectors can catch the bug, there's no need for KMSAN. KMSAN is for the edge cases. Looking at the code changes: the patch introduces a new field, `data_in_bytes`, within `struct iscsi_tcp_task`. Crucially, this field is explicitly initialized to zero in `iscsi_tcp_task_init()`. The code also increments `data_in_bytes` in `iscsi_tcp_data_in()`. I've made a quick mental note to search where `struct iscsi_tcp_task` is allocated to be 100% sure, but the initialization looks safe so far. The important point is that this patch explicitly zeros out memory. This seems like it's preventing uninitialized memory issues, rather than introducing them. My initial gut feeling is that this patch is addressing a potential uninitialized memory issue, and the patch, in theory, prevents the problem, so I don't see any immediate KMSAN concerns. It's a protection mechanism. I'll need to do some more digging, but at this point, I don't believe this patch warrants a dedicated KMSAN fuzzing session. I need to be absolutely certain before recommending the additional resource cost.
46/3	2026/10/08 05:23	tool	grepper	0m Args: { "Expression": "iscsi_tcp_task", "PathPrefixes": [ "drivers/scsi/" ] } Results: { "Output": "drivers/scsi/cxgbi/cxgb3i/cxgb3i.c=104=static struct iscsi_transport cxgb3i_iscsi_transport = {\n--\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-130-\t/* task /\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:131:\t.init_task\t= iscsi_tcp_task_init,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c:132:\t.xmit_task\t= iscsi_tcp_task_xmit,\ndrivers/scsi/cxgbi/cxgb3i/cxgb3i.c-133-\t.cleanup_task\t= cxgbi_cleanup_task,\n--\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c=122=static struct iscsi_transport cxgb4i_iscsi_transport = {\n--\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-147-\t/ task /\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:148:\t.init_task\t= iscsi_tcp_task_init,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c:149:\t.xmit_task\t= iscsi_tcp_task_xmit,\ndrivers/scsi/cxgbi/cxgb4i/cxgb4i.c-150-\t.cleanup_task\t= cxgbi_cleanup_task,\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1508=skb_read_pdu_bhs(struct cxgbi_sock csk, struct iscsi_conn conn,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1543-\t\tif (task \u0026\u0026 task-\u003esc) {\ndrivers/scsi/cxgbi/libcxgbi.c:1544:\t\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1545-\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1885=int cxgbi_conn_alloc_pdu(struct iscsi_task task, u8 op)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1892-\tstruct cxgbi_sock csk = cconn-\u003ecep ? cconn-\u003ecep-\u003ecsk : NULL;\ndrivers/scsi/cxgbi/libcxgbi.c:1893:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-1894-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2061=cxgbi_prep_iso_info(struct iscsi_task task, struct sk_buff skb,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2068-\tstruct iscsi_session session = conn-\u003esession;\ndrivers/scsi/cxgbi/libcxgbi.c:2069:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2070-\tu32 burst_size = 0, r2t_dlength = 0, dlength;\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2144=int cxgbi_conn_init_pdu(struct iscsi_task task, unsigned int offset,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2147-\tstruct iscsi_conn conn = task-\u003econn;\ndrivers/scsi/cxgbi/libcxgbi.c:2148:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2149-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2361=int cxgbi_conn_xmit_pdu(struct iscsi_task task)\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2364-\tstruct cxgbi_conn cconn = tcp_conn-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c:2365:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2366-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2470=void cxgbi_cleanup_task(struct iscsi_task task)\ndrivers/scsi/cxgbi/libcxgbi.c-2471-{\ndrivers/scsi/cxgbi/libcxgbi.c:2472:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/cxgbi/libcxgbi.c-2473-\tstruct cxgbi_task_data tdata = iscsi_task_cxgbi_data(task);\n--\ndrivers/scsi/cxgbi/libcxgbi.c=2726=struct iscsi_cls_session cxgbi_create_session(struct iscsi_endpoint ep,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2748-\t\t\t\t\tcmds_max, 0,\ndrivers/scsi/cxgbi/libcxgbi.c:2749:\t\t\t\t\tsizeof(struct iscsi_tcp_task) +\ndrivers/scsi/cxgbi/libcxgbi.c-2750-\t\t\t\t\tsizeof(struct cxgbi_task_data),\n--\ndrivers/scsi/cxgbi/libcxgbi.h=539=struct cxgbi_task_data {\n--\ndrivers/scsi/cxgbi/libcxgbi.h-555-#define iscsi_task_cxgbi_data(task) \\\ndrivers/scsi/cxgbi/libcxgbi.h:556:\t((task)-\u003edd_data + sizeof(struct iscsi_tcp_task))\ndrivers/scsi/cxgbi/libcxgbi.h-557-\n--\ndrivers/scsi/iscsi_tcp.c=450=static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn conn, void hdr,\n--\ndrivers/scsi/iscsi_tcp.c-465-\t place the digest into the same buffer. We make\ndrivers/scsi/iscsi_tcp.c:466:\t * sure that both iscsi_tcp_task and mtask have\ndrivers/scsi/iscsi_tcp.c-467-\t * sufficient room.\n--\ndrivers/scsi/iscsi_tcp.c=566=static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task task, uint8_t opcode)\ndrivers/scsi/iscsi_tcp.c-567-{\ndrivers/scsi/iscsi_tcp.c:568:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/iscsi_tcp.c-569-\n--\ndrivers/scsi/iscsi_tcp.c=878=iscsi_sw_tcp_session_create(struct iscsi_endpoint ep, uint16_t cmds_max,\n--\ndrivers/scsi/iscsi_tcp.c-913-\t\t\t\t\t cmds_max, 0,\ndrivers/scsi/iscsi_tcp.c:914:\t\t\t\t\t sizeof(struct iscsi_tcp_task) +\ndrivers/scsi/iscsi_tcp.c-915-\t\t\t\t\t sizeof(struct iscsi_sw_tcp_hdrbuf),\n--\ndrivers/scsi/iscsi_tcp.c=1049=static struct iscsi_transport iscsi_sw_tcp_transport = {\n--\ndrivers/scsi/iscsi_tcp.c-1073-\t/ iscsi task/cmd helpers /\ndrivers/scsi/iscsi_tcp.c:1074:\t.init_task\t\t= iscsi_tcp_task_init,\ndrivers/scsi/iscsi_tcp.c:1075:\t.xmit_task\t\t= iscsi_tcp_task_xmit,\ndrivers/scsi/iscsi_tcp.c-1076-\t.cleanup_task\t\t= iscsi_tcp_cleanup_task,\n--\ndrivers/scsi/libiscsi_tcp.c=414=static void iscsi_tcp_zero_unread(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-415-{\ndrivers/scsi/libiscsi_tcp.c:416:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-417-\tstruct scsi_cmnd sc = task-\u003esc;\n--\ndrivers/scsi/libiscsi_tcp.c=503=void iscsi_tcp_cleanup_task(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-504-{\ndrivers/scsi/libiscsi_tcp.c:505:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-506-\tstruct iscsi_r2t_info r2t;\n--\ndrivers/scsi/libiscsi_tcp.c=535=static int iscsi_tcp_data_in(struct iscsi_conn conn, struct iscsi_task task)\n--\ndrivers/scsi/libiscsi_tcp.c-537-\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c:538:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-539-\tstruct iscsi_data_rsp rhdr = (struct iscsi_data_rsp )tcp_conn-\u003ein.hdr;\n--\ndrivers/scsi/libiscsi_tcp.c=586=static int iscsi_tcp_r2t_rsp(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-588-\tstruct iscsi_session session = conn-\u003esession;\ndrivers/scsi/libiscsi_tcp.c:589:\tstruct iscsi_tcp_task tcp_task;\ndrivers/scsi/libiscsi_tcp.c-590-\tstruct iscsi_tcp_conn tcp_conn;\n--\ndrivers/scsi/libiscsi_tcp.c=746=iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-788-\t\tif (tcp_conn-\u003ein.datalen) {\ndrivers/scsi/libiscsi_tcp.c:789:\t\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-790-\t\t\tu32 rx_crcp = NULL;\n--\ndrivers/scsi/libiscsi_tcp.c=1051=EXPORT_SYMBOL_GPL(iscsi_tcp_recv_skb);\n--\ndrivers/scsi/libiscsi_tcp.c-1053-/*\ndrivers/scsi/libiscsi_tcp.c:1054: iscsi_tcp_task_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands\ndrivers/scsi/libiscsi_tcp.c-1055- * @task: scsi command task\ndrivers/scsi/libiscsi_tcp.c-1056- /\ndrivers/scsi/libiscsi_tcp.c:1057:int iscsi_tcp_task_init(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-1058-{\ndrivers/scsi/libiscsi_tcp.c:1059:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-1060-\tstruct iscsi_conn conn = task-\u003econn;\n--\ndrivers/scsi/libiscsi_tcp.c-1087-}\ndrivers/scsi/libiscsi_tcp.c:1088:EXPORT_SYMBOL_GPL(iscsi_tcp_task_init);\ndrivers/scsi/libiscsi_tcp.c-1089-\ndrivers/scsi/libiscsi_tcp.c=1090=static struct iscsi_r2t_info iscsi_tcp_get_curr_r2t(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-1091-{\ndrivers/scsi/libiscsi_tcp.c:1092:\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-1093-\tstruct iscsi_r2t_info r2t = NULL;\n--\ndrivers/scsi/libiscsi_tcp.c-1126-/*\ndrivers/scsi/libiscsi_tcp.c:1127: iscsi_tcp_task_xmit - xmit normal PDU task\ndrivers/scsi/libiscsi_tcp.c-1128- * @task: iscsi command task\n--\ndrivers/scsi/libiscsi_tcp.c-1133- /\ndrivers/scsi/libiscsi_tcp.c:1134:int iscsi_tcp_task_xmit(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-1135-{\n--\ndrivers/scsi/libiscsi_tcp.c-1183-}\ndrivers/scsi/libiscsi_tcp.c:1184:EXPORT_SYMBOL_GPL(iscsi_tcp_task_xmit);\ndrivers/scsi/libiscsi_tcp.c-1185-\n--\ndrivers/scsi/libiscsi_tcp.c=1219=int iscsi_tcp_r2tpool_alloc(struct iscsi_session session)\n--\ndrivers/scsi/libiscsi_tcp.c-1228-\t struct iscsi_task task = session-\u003ecmds[cmd_i];\ndrivers/scsi/libiscsi_tcp.c:1229:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-1230-\n--\ndrivers/scsi/libiscsi_tcp.c-1258-\t\tstruct iscsi_task task = session-\u003ecmds[i];\ndrivers/scsi/libiscsi_tcp.c:1259:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-1260-\n--\ndrivers/scsi/libiscsi_tcp.c=1268=void iscsi_tcp_r2tpool_free(struct iscsi_session session)\n--\ndrivers/scsi/libiscsi_tcp.c-1273-\t\tstruct iscsi_task task = session-\u003ecmds[i];\ndrivers/scsi/libiscsi_tcp.c:1274:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\ndrivers/scsi/libiscsi_tcp.c-1275-\n" }
47/3	2026/10/08 05:23	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 10157 output: 41 thoughts: 24 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: Diving into `drivers/scsi/libiscsi_tcp.c` Alright, I'm going to take a look at `drivers/scsi/libiscsi_tcp.c`. Specifically, I need to zoom in on the code around the patched lines. I'm assuming that the diffs are going to give me some insight into the recent change. I'm probably looking for clues about the bug that was fixed or the new functionality that was added. The context around those patches is crucial, of course. I'll be keeping an eye out for potential side effects or areas that might require further scrutiny, given my experience with this subsystem. This will be the best way to get to the core of this change and determine its impact.
48/3	2026/10/08 05:23	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 400, "LineCount": 80 } Results: { "Contents": " 400:\t/*\n 401:\t iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent\n 402:\t * @task: scsi command task\n 403:\t \n 404:\t A target can end a read without sending all of the data, in any of the ways\n 405:\t * a completion can be reported. Rather than predict from the status, the\n 406:\t * sense and the residual whether the buffer was promised in full, zero the\n 407:\t * bytes that did not arrive. Whatever the midlayer then reports as\n 408:\t * transferred, the caller sees zeroes and not the previous contents of those\n 409:\t * pages.\n 410:\t \n 411:\t The continuity check in iscsi_tcp_data_in() means the bytes that did not\n 412:\t * arrive are exactly the tail, so one range covers them.\n 413:\t /\n 414:\tstatic void iscsi_tcp_zero_unread(struct iscsi_task task)\n 415:\t{\n 416:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\n 417:\t\tstruct scsi_cmnd sc = task-\u003esc;\n 418:\t\n 419:\t\tif (!sc \|\| sc-\u003esc_data_direction != DMA_FROM_DEVICE \|\|\n 420:\t\t tcp_task-\u003edata_in_bytes \u003e= sc-\u003esdb.length)\n 421:\t\t\treturn;\n 422:\t\n 423:\t\tsg_zero_buffer(sc-\u003esdb.table.sgl, sc-\u003esdb.table.nents,\n 424:\t\t\t sc-\u003esdb.length - tcp_task-\u003edata_in_bytes,\n 425:\t\t\t tcp_task-\u003edata_in_bytes);\n 426:\t}\n 427:\t\n 428:\t/*\n 429:\t iscsi_tcp_complete_cmd - zero any unread tail, then complete the command\n 430:\t * @conn: iscsi connection\n 431:\t * @hdr: the PDU carrying the status\n 432:\t * @data: data segment of that PDU, if it has one\n 433:\t * @datalen: length of @data\n 434:\t \n 435:\t back_lock is taken once for the lookup, the fill and the completion.\n 436:\t /\n 437:\tstatic int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr,\n 438:\t\t\t\t\t char data, int datalen)\n 439:\t{\n 440:\t\tstruct iscsi_task task;\n 441:\t\tint rc;\n 442:\t\n 443:\t\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\n 444:\t\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\n 445:\t\tif (!task) {\n 446:\t\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n 447:\t\t\treturn ISCSI_ERR_BAD_ITT;\n 448:\t\t}\n 449:\t\tiscsi_tcp_zero_unread(task);\n 450:\t\trc = __iscsi_complete_pdu(conn, hdr, data, datalen);\n 451:\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n 452:\t\treturn rc;\n 453:\t}\n 454:\t\n 455:\t/\n 456:\t * Handle incoming reply to any other type of command\n 457:\t /\n 458:\tstatic int\n 459:\tiscsi_tcp_data_recv_done(struct iscsi_tcp_conn tcp_conn,\n 460:\t\t\t\t struct iscsi_segment segment)\n 461:\t{\n 462:\t\tstruct iscsi_conn conn = tcp_conn-\u003eiscsi_conn;\n 463:\t\tint rc = 0;\n 464:\t\n 465:\t\tif (!iscsi_tcp_dgst_verify(tcp_conn, segment))\n 466:\t\t\treturn ISCSI_ERR_DATA_DGST;\n 467:\t\n 468:\t\tif ((tcp_conn-\u003ein.hdr-\u003eopcode \u0026 ISCSI_OPCODE_MASK) ==\n 469:\t\t ISCSI_OP_SCSI_CMD_RSP)\n 470:\t\t\trc = iscsi_tcp_complete_cmd(conn, tcp_conn-\u003ein.hdr, conn-\u003edata,\n 471:\t\t\t\t\t\t tcp_conn-\u003ein.datalen);\n 472:\t\telse\n 473:\t\t\trc = iscsi_complete_pdu(conn, tcp_conn-\u003ein.hdr, conn-\u003edata,\n 474:\t\t\t\t\t\ttcp_conn-\u003ein.datalen);\n 475:\t\tif (rc)\n 476:\t\t\treturn rc;\n 477:\t\n 478:\t\tiscsi_tcp_hdr_recv_prep(tcp_conn);\n 479:\t\treturn 0;\n" }
49/3	2026/10/08 05:23	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 11752 output: 19 thoughts: 146 Thoughts: Okay, here's my summary, taking the perspective of someone deeply familiar with this level of systems work: Investigating the `iscsi_tcp_zero_unread` Implementation Alright, I need to get to the bottom of this. First, the most direct path would be to check the Git commit log to see what changes were made. I'll need to find the upstream commit, or see what commit implemented this change. I'll start with a quick `git log -1` or something similar, and if I can use grepper or a search, I will. But, let's remember `git log` isn't a tool in the strict sense, whereas grepper is. Hang on… what commit introduced this in the Linux kernel itself? I need to track this change back. Then, I can search for "iscsi_tcp_zero_unread" using grepper or a comparable tool in the Git history if necessary. Keep in mind grepper is for source trees, which is what I want. Wait a second… I can just grep for `iscsi_tcp_zero_unread`! I've already seen it in the diff. Let's start with that! Okay, now that I know what to look for, let's explore what `sg_zero_buffer` actually does. Understanding this will be critical to grasping the implications of this change.
50/3	2026/10/08 05:24	tool	grepper	0m Args: { "Expression": "sg_zero_buffer" } Results: { "Output": "crypto/krb5/rfc3961_simplified.c=540=ssize_t krb5_aead_encrypt(const struct krb5_enctype krb5,\n--\ncrypto/krb5/rfc3961_simplified.c-580-\tif (pad_len) {\ncrypto/krb5/rfc3961_simplified.c:581:\t\tdone = sg_zero_buffer(sg, nr_sg, pad_len, data_offset + data_len);\ncrypto/krb5/rfc3961_simplified.c-582-\t\tif (done != pad_len)\n--\ncrypto/krb5/rfc8009_aes2.c=172=static ssize_t rfc8009_encrypt(const struct krb5_enctype krb5,\n--\ncrypto/krb5/rfc8009_aes2.c-217-\tif (pad_len) {\ncrypto/krb5/rfc8009_aes2.c:218:\t\tdone = sg_zero_buffer(sg, nr_sg, pad_len, data_offset + data_len);\ncrypto/krb5/rfc8009_aes2.c-219-\t\tif (done != pad_len)\n--\ndrivers/crypto/ccree/cc_aead.c=209=static void cc_aead_complete(struct device dev, void cc_req, int err)\n--\ndrivers/crypto/ccree/cc_aead.c-235-\t\t\t /\ndrivers/crypto/ccree/cc_aead.c:236:\t\t\tsg_zero_buffer(areq-\u003edst, sg_nents(areq-\u003edst),\ndrivers/crypto/ccree/cc_aead.c-237-\t\t\t\t areq-\u003ecryptlen, areq-\u003eassoclen);\n--\ndrivers/crypto/starfive/jh7110-aes.c=634=static int starfive_aes_aead_do_one_req(struct crypto_engine engine, void areq)\n--\ndrivers/crypto/starfive/jh7110-aes.c-678-\tif (cryp-\u003etotal_in)\ndrivers/crypto/starfive/jh7110-aes.c:679:\t\tsg_zero_buffer(rctx-\u003ein_sg, sg_nents(rctx-\u003ein_sg),\ndrivers/crypto/starfive/jh7110-aes.c-680-\t\t\t rctx-\u003ein_sg-\u003elength - cryp-\u003etotal_in,\n--\ndrivers/nvme/target/admin-cmd.c=999=static void nvmet_execute_identify_desclist(struct nvmet_req req)\n--\ndrivers/nvme/target/admin-cmd.c-1028-\ndrivers/nvme/target/admin-cmd.c:1029:\tif (sg_zero_buffer(req-\u003esg, req-\u003esg_cnt, NVME_IDENTIFY_DATA_SIZE - off,\ndrivers/nvme/target/admin-cmd.c-1030-\t\t\toff) != NVME_IDENTIFY_DATA_SIZE - off)\n--\ndrivers/nvme/target/core.c=111=u16 nvmet_zero_sgl(struct nvmet_req req, off_t off, size_t len)\ndrivers/nvme/target/core.c-112-{\ndrivers/nvme/target/core.c:113:\tif (sg_zero_buffer(req-\u003esg, req-\u003esg_cnt, len, off) != len) {\ndrivers/nvme/target/core.c-114-\t\treq-\u003eerror_loc = offsetof(struct nvme_common_command, dptr);\n--\ndrivers/scsi/libiscsi_tcp.c=414=static void iscsi_tcp_zero_unread(struct iscsi_task task)\n--\ndrivers/scsi/libiscsi_tcp.c-422-\ndrivers/scsi/libiscsi_tcp.c:423:\tsg_zero_buffer(sc-\u003esdb.table.sgl, sc-\u003esdb.table.nents,\ndrivers/scsi/libiscsi_tcp.c-424-\t\t sc-\u003esdb.length - tcp_task-\u003edata_in_bytes,\n--\ndrivers/scsi/scsi_debug.c=4405=static int resp_read_tape(struct scsi_cmnd scp, struct sdebug_dev_info devip)\n--\ndrivers/scsi/scsi_debug.c-4459-\t\t}\ndrivers/scsi/scsi_debug.c:4460:\t\tsg_zero_buffer(sdb-\u003etable.sgl, sdb-\u003etable.nents,\ndrivers/scsi/scsi_debug.c-4461-\t\t\tsize, i * size);\n--\ndrivers/scsi/scsi_lib.c=1154=blk_status_t scsi_alloc_sgtables(struct scsi_cmnd cmd)\n--\ndrivers/scsi/scsi_lib.c-1192-\t\tlast_sg-\u003elength += pad_len;\ndrivers/scsi/scsi_lib.c:1193:\t\tsg_zero_buffer(last_sg, 1, pad_len, data_len);\ndrivers/scsi/scsi_lib.c-1194-\t\tcmd-\u003eextra_len += pad_len;\n--\ninclude/linux/scatterlist.h=526=size_t sg_pcopy_to_buffer(struct scatterlist sgl, unsigned int nents,\ninclude/linux/scatterlist.h-527-\t\t\t void buf, size_t buflen, off_t skip);\ninclude/linux/scatterlist.h:528:size_t sg_zero_buffer(struct scatterlist sgl, unsigned int nents,\ninclude/linux/scatterlist.h-529-\t\t size_t buflen, off_t skip);\n--\nlib/scatterlist.c=1072=EXPORT_SYMBOL(sg_pcopy_to_buffer);\n--\nlib/scatterlist.c-1074-/*\nlib/scatterlist.c:1075: sg_zero_buffer - Zero-out a part of a SG list\nlib/scatterlist.c-1076- * @sgl:\t\t The SG list\n--\nlib/scatterlist.c-1082- */\nlib/scatterlist.c:1083:size_t sg_zero_buffer(struct scatterlist sgl, unsigned int nents,\nlib/scatterlist.c-1084-\t\t size_t buflen, off_t skip)\n--\nlib/scatterlist.c-1106-}\nlib/scatterlist.c:1107:EXPORT_SYMBOL(sg_zero_buffer);\nlib/scatterlist.c-1108-\n" }
51/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 13924 output: 41 thoughts: 72 Thoughts: Here's my summary, as I delve into the code: Diving into the iSCSI TCP Data Flow Okay, let's get down to brass tacks. I need to understand the data flow in the iSCSI TCP layer. I'm going to jump straight into `libiscsi_tcp.c`, specifically focusing on `iscsi_tcp_data_in()` and `iscsi_tcp_hdr_dissect()`. These seem like the critical functions for handling incoming data, dissecting headers, and figuring out what's going on. I'll need to understand how the TCP data is interpreted and passed up the stack. To get a handle on the key logic, I'm going to start by going over lines 500 to 860 of `drivers/scsi/libiscsi_tcp.c`. This should give me enough context to understand the core data handling process, how the iSCSI protocol is layered over TCP, and, hopefully, how the session state is managed. I expect there will be header parsing, checksum verification (likely!), and data buffering or passing off to higher levels within the iSCSI stack. I'm particularly interested in how the data is reassembled if it's fragmented.
52/3	2026/10/08 05:24	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 535, "LineCount": 60 } Results: { "Contents": " 535:\tstatic int iscsi_tcp_data_in(struct iscsi_conn conn, struct iscsi_task task)\n 536:\t{\n 537:\t\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\n 538:\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\n 539:\t\tstruct iscsi_data_rsp rhdr = (struct iscsi_data_rsp )tcp_conn-\u003ein.hdr;\n 540:\t\tint datasn = be32_to_cpu(rhdr-\u003edatasn);\n 541:\t\tunsigned total_in_length = task-\u003esc-\u003esdb.length;\n 542:\t\n 543:\t\tif (task-\u003esc-\u003esc_data_direction != DMA_FROM_DEVICE)\n 544:\t\t\treturn ISCSI_ERR_PROTO;\n 545:\t\n 546:\t\t/\n 547:\t\t lib iscsi will update this in the completion handling if there\n 548:\t\t * is status.\n 549:\t\t /\n 550:\t\tif (!(rhdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS))\n 551:\t\t\tiscsi_update_cmdsn(conn-\u003esession, (struct iscsi_nopin)rhdr);\n 552:\t\n 553:\t\tif (tcp_conn-\u003ein.datalen == 0)\n 554:\t\t\treturn 0;\n 555:\t\n 556:\t\tif (tcp_task-\u003eexp_datasn != datasn) {\n 557:\t\t\tISCSI_DBG_TCP(conn, \"task-\u003eexp_datasn(%d) != rhdr-\u003edatasn(%d)\"\n 558:\t\t\t\t \"\\n\", tcp_task-\u003eexp_datasn, datasn);\n 559:\t\t\treturn ISCSI_ERR_DATASN;\n 560:\t\t}\n 561:\t\n 562:\t\ttcp_task-\u003eexp_datasn++;\n 563:\t\n 564:\t\ttcp_task-\u003edata_offset = be32_to_cpu(rhdr-\u003eoffset);\n 565:\t\tif (tcp_task-\u003edata_offset + tcp_conn-\u003ein.datalen \u003e total_in_length) {\n 566:\t\t\tISCSI_DBG_TCP(conn, \"data_offset(%d) + data_len(%d) \u003e \"\n 567:\t\t\t\t \"total_length_in(%d)\\n\", tcp_task-\u003edata_offset,\n 568:\t\t\t\t tcp_conn-\u003ein.datalen, total_in_length);\n 569:\t\t\treturn ISCSI_ERR_DATA_OFFSET;\n 570:\t\t}\n 571:\t\n 572:\t\tif (tcp_task-\u003edata_offset != tcp_task-\u003edata_in_bytes)\n 573:\t\t\treturn ISCSI_ERR_DATA_OFFSET;\n 574:\t\n 575:\t\ttcp_task-\u003edata_in_bytes += tcp_conn-\u003ein.datalen;\n 576:\t\n 577:\t\tconn-\u003edatain_pdus_cnt++;\n 578:\t\treturn 0;\n 579:\t}\n 580:\t\n 581:\t/*\n 582:\t iscsi_tcp_r2t_rsp - iSCSI R2T Response processing\n 583:\t * @conn: iscsi connection\n 584:\t * @hdr: PDU header\n 585:\t /\n 586:\tstatic int iscsi_tcp_r2t_rsp(struct iscsi_conn conn, struct iscsi_hdr hdr)\n 587:\t{\n 588:\t\tstruct iscsi_session session = conn-\u003esession;\n 589:\t\tstruct iscsi_tcp_task tcp_task;\n 590:\t\tstruct iscsi_tcp_conn tcp_conn;\n 591:\t\tstruct iscsi_r2t_rsp rhdr;\n 592:\t\tstruct iscsi_r2t_info r2t;\n 593:\t\tstruct iscsi_task *task;\n 594:\t\tu32 data_length;\n" }
53/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 15395 output: 41 thoughts: 32 Thoughts: Okay, here's my interpretation of what I should be summarizing, rendered as a first-person perspective for an expert: Diving into `libiscsi_tcp.c` Alright, let's get down to it. We need to focus in on `drivers/scsi/libiscsi_tcp.c`. Specifically, I want to take a close look at lines 720 through 865. This section is key for understanding [Insert the relevant context here based on your knowledge of iSCSI and networking protocols; e.g., "how connection establishment is handled," "the error handling for socket operations," or "the specifics of data transfer acknowledgements."]. I'm expecting to see [ Insert your expectations here; e.g. "some interesting interaction with the socket layer," "how they're managing flow control," or "how they're handling iSCSI PDU framing in that TCP context."]. I’ll be paying close attention to [ Mention specific areas of interest or potential concerns; e.g., "any potential race conditions," "how they're handling timeouts," or "the use of specific data structures."] in particular. Hopefully, this section helps resolve the [ Insert your reason for wanting to review that section; e.g., "performance issue we're seeing," "potential security vulnerability," or "unexplained behavior in our tests."].
54/3	2026/10/08 05:24	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 720, "LineCount": 80 } Results: { "Contents": " 720:\t\n 721:\t\tif (!iscsi_tcp_dgst_verify(tcp_conn, segment))\n 722:\t\t\treturn ISCSI_ERR_DATA_DGST;\n 723:\t\n 724:\t\t/* check for non-exceptional status /\n 725:\t\tif (hdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS) {\n 726:\t\t\trc = iscsi_tcp_complete_cmd(conn, tcp_conn-\u003ein.hdr, NULL, 0);\n 727:\t\t\tif (rc)\n 728:\t\t\t\treturn rc;\n 729:\t\t}\n 730:\t\n 731:\t\tiscsi_tcp_hdr_recv_prep(tcp_conn);\n 732:\t\treturn 0;\n 733:\t}\n 734:\t\n 735:\t/\n 736:\t iscsi_tcp_hdr_dissect - process PDU header\n 737:\t * @conn: iSCSI connection\n 738:\t * @hdr: PDU header\n 739:\t \n 740:\t This function analyzes the header of the PDU received,\n 741:\t * and performs several sanity checks. If the PDU is accompanied\n 742:\t * by data, the receive buffer is set up to copy the incoming data\n 743:\t * to the correct location.\n 744:\t /\n 745:\tstatic int\n 746:\tiscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n 747:\t{\n 748:\t\tint rc = 0, opcode, ahslen;\n 749:\t\tstruct iscsi_tcp_conn tcp_conn = conn-\u003edd_data;\n 750:\t\tstruct iscsi_task task;\n 751:\t\n 752:\t\t/ verify PDU length /\n 753:\t\ttcp_conn-\u003ein.datalen = ntoh24(hdr-\u003edlength);\n 754:\t\tif (tcp_conn-\u003ein.datalen \u003e conn-\u003emax_recv_dlength) {\n 755:\t\t\tiscsi_conn_printk(KERN_ERR, conn,\n 756:\t\t\t\t\t \"iscsi_tcp: datalen %d \u003e %d\\n\",\n 757:\t\t\t\t\t tcp_conn-\u003ein.datalen, conn-\u003emax_recv_dlength);\n 758:\t\t\treturn ISCSI_ERR_DATALEN;\n 759:\t\t}\n 760:\t\n 761:\t\t/ Additional header segments. So far, we don't\n 762:\t\t * process additional headers.\n 763:\t\t /\n 764:\t\tahslen = hdr-\u003ehlength \u003c\u003c 2;\n 765:\t\n 766:\t\topcode = hdr-\u003eopcode \u0026 ISCSI_OPCODE_MASK;\n 767:\t\t/ verify itt (itt encoding: age+cid+itt) /\n 768:\t\trc = iscsi_verify_itt(conn, hdr-\u003eitt);\n 769:\t\tif (rc)\n 770:\t\t\treturn rc;\n 771:\t\n 772:\t\tISCSI_DBG_TCP(conn, \"opcode 0x%x ahslen %d datalen %d\\n\",\n 773:\t\t\t opcode, ahslen, tcp_conn-\u003ein.datalen);\n 774:\t\n 775:\t\tswitch(opcode) {\n 776:\t\tcase ISCSI_OP_SCSI_DATA_IN:\n 777:\t\t\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\n 778:\t\t\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\n 779:\t\t\tif (!task)\n 780:\t\t\t\trc = ISCSI_ERR_BAD_ITT;\n 781:\t\t\telse\n 782:\t\t\t\trc = iscsi_tcp_data_in(conn, task);\n 783:\t\t\tif (rc) {\n 784:\t\t\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n 785:\t\t\t\tbreak;\n 786:\t\t\t}\n 787:\t\n 788:\t\t\tif (tcp_conn-\u003ein.datalen) {\n 789:\t\t\t\tstruct iscsi_tcp_task tcp_task = task-\u003edd_data;\n 790:\t\t\t\tu32 rx_crcp = NULL;\n 791:\t\t\t\tstruct scsi_data_buffer sdb = \u0026task-\u003esc-\u003esdb;\n 792:\t\n 793:\t\t\t\t/\n 794:\t\t\t\t Setup copy of Data-In into the struct scsi_cmnd\n 795:\t\t\t\t * Scatterlist case:\n 796:\t\t\t\t * We set up the iscsi_segment to point to the next\n 797:\t\t\t\t * scatterlist entry to copy to. As we go along,\n 798:\t\t\t\t * we move on to the next scatterlist entry and\n 799:\t\t\t\t * update the digest per-entry.\n" }
55/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 17070 output: 41 thoughts: 19 Thoughts: Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person: Diving Deeper into the iSCSI TCP Header Dissection Alright, so the call stack has led me here to `iscsi_tcp_hdr_dissect`. This is the critical routine, the heart of how we unravel iSCSI traffic riding on TCP. I know this code well, but a quick refresher never hurts, especially when tracking down a potential anomaly. My immediate focus? I need to understand how the function handles the TCP header data: what fields it's extracting, how it's validating them, and where it's storing the decoded information. I want to see the error checking and how it handles different scenarios. I'm particularly interested in looking at the edge cases here – unusual combinations of flags or lengths, malformed packets, anything that might be introducing subtle bugs or performance bottlenecks. I need to understand the implications of any assumptions this function makes about the underlying TCP connection and how that might impact performance. Is it thread safe? If I see any issues or have some questions, I'll be sure to raise them with the team and document them appropriately.
56/3	2026/10/08 05:24	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi_tcp.c", "FirstLine": 800, "LineCount": 80 } Results: { "Contents": " 800:\t\t\t\t /\n 801:\t\t\t\tif (conn-\u003edatadgst_en \u0026\u0026\n 802:\t\t\t\t !(conn-\u003esession-\u003ett-\u003ecaps \u0026 CAP_DIGEST_OFFLOAD))\n 803:\t\t\t\t\trx_crcp = tcp_conn-\u003erx_crcp;\n 804:\t\n 805:\t\t\t\tISCSI_DBG_TCP(conn, \"iscsi_tcp_begin_data_in( \"\n 806:\t\t\t\t\t \"offset=%d, datalen=%d)\\n\",\n 807:\t\t\t\t\t tcp_task-\u003edata_offset,\n 808:\t\t\t\t\t tcp_conn-\u003ein.datalen);\n 809:\t\t\t\ttask-\u003elast_xfer = jiffies;\n 810:\t\t\t\trc = iscsi_segment_seek_sg(\u0026tcp_conn-\u003ein.segment,\n 811:\t\t\t\t\t\t\t sdb-\u003etable.sgl,\n 812:\t\t\t\t\t\t\t sdb-\u003etable.nents,\n 813:\t\t\t\t\t\t\t tcp_task-\u003edata_offset,\n 814:\t\t\t\t\t\t\t tcp_conn-\u003ein.datalen,\n 815:\t\t\t\t\t\t\t iscsi_tcp_process_data_in,\n 816:\t\t\t\t\t\t\t rx_crcp);\n 817:\t\t\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n 818:\t\t\t\treturn rc;\n 819:\t\t\t}\n 820:\t\t\t/\n 821:\t\t\t * A Data-In with no data segment can still carry the status,\n 822:\t\t\t * and it completes the command here rather than from\n 823:\t\t\t * iscsi_tcp_process_data_in(), so fill the tail on this path\n 824:\t\t\t * too.\n 825:\t\t\t /\n 826:\t\t\tif (hdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS)\n 827:\t\t\t\tiscsi_tcp_zero_unread(task);\n 828:\t\t\trc = __iscsi_complete_pdu(conn, hdr, NULL, 0);\n 829:\t\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n 830:\t\t\tbreak;\n 831:\t\tcase ISCSI_OP_R2T:\n 832:\t\t\tif (ahslen) {\n 833:\t\t\t\trc = ISCSI_ERR_AHSLEN;\n 834:\t\t\t\tbreak;\n 835:\t\t\t}\n 836:\t\t\trc = iscsi_tcp_r2t_rsp(conn, hdr);\n 837:\t\t\tbreak;\n 838:\t\tcase ISCSI_OP_SCSI_CMD_RSP:\n 839:\t\tcase ISCSI_OP_LOGIN_RSP:\n 840:\t\tcase ISCSI_OP_TEXT_RSP:\n 841:\t\tcase ISCSI_OP_REJECT:\n 842:\t\tcase ISCSI_OP_ASYNC_EVENT:\n 843:\t\t\t/\n 844:\t\t\t * It is possible that we could get a PDU with a buffer larger\n 845:\t\t\t * than 8K, but there are no targets that currently do this.\n 846:\t\t\t * For now we fail until we find a vendor that needs it\n 847:\t\t\t /\n 848:\t\t\tif (ISCSI_DEF_MAX_RECV_SEG_LEN \u003c tcp_conn-\u003ein.datalen) {\n 849:\t\t\t\tiscsi_conn_printk(KERN_ERR, conn,\n 850:\t\t\t\t\t\t \"iscsi_tcp: received buffer of \"\n 851:\t\t\t\t\t\t \"len %u but conn buffer is only %u \"\n 852:\t\t\t\t\t\t \"(opcode %0x)\\n\",\n 853:\t\t\t\t\t\t tcp_conn-\u003ein.datalen,\n 854:\t\t\t\t\t\t ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);\n 855:\t\t\t\trc = ISCSI_ERR_PROTO;\n 856:\t\t\t\tbreak;\n 857:\t\t\t}\n 858:\t\n 859:\t\t\tif (opcode == ISCSI_OP_SCSI_CMD_RSP \u0026\u0026 !tcp_conn-\u003ein.datalen) {\n 860:\t\t\t\trc = iscsi_tcp_complete_cmd(conn, hdr, NULL, 0);\n 861:\t\t\t\tbreak;\n 862:\t\t\t}\n 863:\t\n 864:\t\t\t/ If there's data coming in with the response,\n 865:\t\t\t * receive it to the connection's buffer.\n 866:\t\t\t */\n 867:\t\t\tif (tcp_conn-\u003ein.datalen) {\n 868:\t\t\t\tiscsi_tcp_data_recv_prep(tcp_conn);\n 869:\t\t\t\treturn 0;\n 870:\t\t\t}\n 871:\t\t\tfallthrough;\n 872:\t\tcase ISCSI_OP_LOGOUT_RSP:\n 873:\t\tcase ISCSI_OP_NOOP_IN:\n 874:\t\tcase ISCSI_OP_SCSI_TMFUNC_RSP:\n 875:\t\t\trc = iscsi_complete_pdu(conn, hdr, NULL, 0);\n 876:\t\t\tbreak;\n 877:\t\tdefault:\n 878:\t\t\trc = ISCSI_ERR_BAD_OPCODE;\n 879:\t\t\tbreak;\n" }
57/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 18722 output: 23 thoughts: 1154 Thoughts: Analyzing the Impact of the `iscsi_tcp_zero_unread` Patch Okay, so I'm diving into this `iscsi_tcp_zero_unread` patch, and my initial thought is: what problem is it trying to solve? The commit message seems straightforward. It mentions that a target might prematurely end a read, leaving the read buffer (`sc->sdb`, I presume) partially populated. This patch zeroes the remaining unread part. But, I need to understand the before state. What exactly was in the rest of `sc->sdb` before this patch? Was it potentially uninitialized memory or stale kernel data? Now, the core of my thought process shifts to a critical question: is this a fix or a potential exposure? Is the patch preventing an info-leak by ensuring zeroed memory, or does it inadvertently expose uninitialized memory that wasn't previously a concern? I need to analyze its context thoroughly. The instructions emphasize that KMSAN is for detecting reads of uninitialized memory and kernel-to-user info-leaks, and that KMSAN should only be used if the patch introduces risks that aren't caught by KASAN, LOCKDEP, or standard bug detectors. I'm especially focused on the specific scenarios listed where KMSAN is needed: 1. Kernel structures sent to user space where fields might be uninitialized. 2. Conditional logic based on potentially uninitialized variables. 3. Allocation of complex data structures where uninitialized fields could be read later. 4. Altered bounds checks that allow access to uninitialized bytes of existing buffers. Now, considering these four points, does this patch modify any of those areas? Item 4 is particularly relevant. Does this patch change how the code operates on existing buffers in a way that allows access to potentially uninitialized bytes? I need to look at the surrounding code, called functions, and callers to see if the patch is changing how the kernel handles data after an incomplete read, for example, is there a chance that uninitialized memory could be read, copied to user space, or used in control flow because of this? So, does this patch fix an uninitialized memory issue? That's what I want to know. And what is this patch under review for? Is it a syzkaller finding, or a response to a CVE? I'm going to search the git history for related commits to gain further insight.
58/3	2026/10/08 05:24	tool	grepper	0m Args: { "Expression": "iscsi_tcp_zero_unread" } Results: { "Output": "drivers/scsi/libiscsi_tcp.c=398=EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep);\n--\ndrivers/scsi/libiscsi_tcp.c-400-/*\ndrivers/scsi/libiscsi_tcp.c:401: iscsi_tcp_zero_unread - zero the part of a read buffer the target never sent\ndrivers/scsi/libiscsi_tcp.c-402- * @task: scsi command task\n--\ndrivers/scsi/libiscsi_tcp.c-413- /\ndrivers/scsi/libiscsi_tcp.c:414:static void iscsi_tcp_zero_unread(struct iscsi_task task)\ndrivers/scsi/libiscsi_tcp.c-415-{\n--\ndrivers/scsi/libiscsi_tcp.c=437=static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr,\n--\ndrivers/scsi/libiscsi_tcp.c-448-\t}\ndrivers/scsi/libiscsi_tcp.c:449:\tiscsi_tcp_zero_unread(task);\ndrivers/scsi/libiscsi_tcp.c-450-\trc = __iscsi_complete_pdu(conn, hdr, data, datalen);\n--\ndrivers/scsi/libiscsi_tcp.c=746=iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-826-\t\tif (hdr-\u003eflags \u0026 ISCSI_FLAG_DATA_STATUS)\ndrivers/scsi/libiscsi_tcp.c:827:\t\t\tiscsi_tcp_zero_unread(task);\ndrivers/scsi/libiscsi_tcp.c-828-\t\trc = __iscsi_complete_pdu(conn, hdr, NULL, 0);\n" }
59/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 20948 output: 23 thoughts: 49 Thoughts: Okay, let's dive into this. Here's my thought process on dissecting this code: Diving into `__iscsi_complete_pdu` and `scsi_cmnd` Alright, I need to get a clear picture of how this `__iscsi_complete_pdu` function works. My immediate focus is on understanding its role in the iSCSI protocol implementation. I'm especially interested in how it interacts with the `scsi_cmnd` buffer. I know that `scsi_cmnd` is crucial for representing SCSI commands, so I want to pinpoint how `__iscsi_complete_pdu` utilizes or modifies it. Let's start by doing a quick search for the function `__iscsi_complete_pdu` in the codebase. That should give me the relevant context and usage examples I need to understand what's happening.
60/3	2026/10/08 05:24	tool	grepper	0m Args: { "Expression": "__iscsi_complete_pdu" } Results: { "Output": "drivers/scsi/be2iscsi/be_main.c=1185=be_complete_logout(struct beiscsi_conn beiscsi_conn,\n--\ndrivers/scsi/be2iscsi/be_main.c-1207-\thdr-\u003eitt = io_task-\u003elibiscsi_itt;\ndrivers/scsi/be2iscsi/be_main.c:1208:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, NULL, 0);\ndrivers/scsi/be2iscsi/be_main.c-1209-}\n--\ndrivers/scsi/be2iscsi/be_main.c=1212=be_complete_tmf(struct beiscsi_conn beiscsi_conn,\n--\ndrivers/scsi/be2iscsi/be_main.c-1228-\thdr-\u003eitt = io_task-\u003elibiscsi_itt;\ndrivers/scsi/be2iscsi/be_main.c:1229:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, NULL, 0);\ndrivers/scsi/be2iscsi/be_main.c-1230-}\n--\ndrivers/scsi/be2iscsi/be_main.c=1268=be_complete_nopin_resp(struct beiscsi_conn beiscsi_conn,\n--\ndrivers/scsi/be2iscsi/be_main.c-1283-\thdr-\u003eitt = io_task-\u003elibiscsi_itt;\ndrivers/scsi/be2iscsi/be_main.c:1284:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, NULL, 0);\ndrivers/scsi/be2iscsi/be_main.c-1285-}\n--\ndrivers/scsi/be2iscsi/be_main.c=1424=beiscsi_complete_pdu(struct beiscsi_conn beiscsi_conn,\n--\ndrivers/scsi/be2iscsi/be_main.c-1462-\t}\ndrivers/scsi/be2iscsi/be_main.c:1463:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )phdr, pdata, dlen);\ndrivers/scsi/be2iscsi/be_main.c-1464-\treturn 0;\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1336=int bnx2i_process_scsi_cmd_resp(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1416-done:\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1417:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr,\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1418-\t\t\t conn-\u003edata, datalen);\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1433=static int bnx2i_process_login_resp(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1483-\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1484:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr,\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1485-\t\tbnx2i_conn-\u003egen_pdu.resp_buf,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1501=static int bnx2i_process_text_resp(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1543-\t}\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1544:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr,\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1545-\t\t\t bnx2i_conn-\u003egen_pdu.resp_buf,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1562=static int bnx2i_process_tmf_resp(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1585-\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1586:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr, NULL, 0);\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1587-done:\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1601=static int bnx2i_process_logout_resp(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1630-\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1631:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr, NULL, 0);\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1632-\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1688=static int bnx2i_process_nopin_mesg(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1724-done:\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1725:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, NULL, 0);\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1726-\tspin_unlock(\u0026session-\u003eback_lock);\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1740=static void bnx2i_process_async_mesg(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1775-\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1776:\t__iscsi_complete_pdu(bnx2i_conn-\u003ecls_conn-\u003edd_data,\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1777-\t\t\t (struct iscsi_hdr )resp_hdr, NULL, 0);\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c=1790=static void bnx2i_process_reject_mesg(struct iscsi_session session,\n--\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1813-\thdr-\u003effffffff = cpu_to_be32(RESERVED_ITT);\ndrivers/scsi/bnx2i/bnx2i_hwi.c:1814:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, conn-\u003edata,\ndrivers/scsi/bnx2i/bnx2i_hwi.c-1815-\t\t\t reject-\u003edata_length);\n--\ndrivers/scsi/libiscsi.c=1199=EXPORT_SYMBOL_GPL(iscsi_itt_to_task);\n--\ndrivers/scsi/libiscsi.c-1201-/*\ndrivers/scsi/libiscsi.c:1202: __iscsi_complete_pdu - complete pdu\ndrivers/scsi/libiscsi.c-1203- * @conn: iscsi conn\n--\ndrivers/scsi/libiscsi.c-1211- /\ndrivers/scsi/libiscsi.c:1212:int __iscsi_complete_pdu(struct iscsi_conn conn, struct iscsi_hdr hdr,\ndrivers/scsi/libiscsi.c-1213-\t\t\t char data, int datalen)\n--\ndrivers/scsi/libiscsi.c-1350-}\ndrivers/scsi/libiscsi.c:1351:EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);\ndrivers/scsi/libiscsi.c-1352-\ndrivers/scsi/libiscsi.c=1353=int iscsi_complete_pdu(struct iscsi_conn conn, struct iscsi_hdr hdr,\n--\ndrivers/scsi/libiscsi.c-1358-\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\ndrivers/scsi/libiscsi.c:1359:\trc = __iscsi_complete_pdu(conn, hdr, data, datalen);\ndrivers/scsi/libiscsi.c-1360-\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n--\ndrivers/scsi/libiscsi_tcp.c=437=static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr,\n--\ndrivers/scsi/libiscsi_tcp.c-449-\tiscsi_tcp_zero_unread(task);\ndrivers/scsi/libiscsi_tcp.c:450:\trc = __iscsi_complete_pdu(conn, hdr, data, datalen);\ndrivers/scsi/libiscsi_tcp.c-451-\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n--\ndrivers/scsi/libiscsi_tcp.c=746=iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-827-\t\t\tiscsi_tcp_zero_unread(task);\ndrivers/scsi/libiscsi_tcp.c:828:\t\trc = __iscsi_complete_pdu(conn, hdr, NULL, 0);\ndrivers/scsi/libiscsi_tcp.c-829-\t\tspin_unlock(\u0026conn-\u003esession-\u003eback_lock);\n--\ndrivers/scsi/qedi/qedi_fw.c=30=static void qedi_process_logout_resp(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-75-\tcmd-\u003estate = RESPONSE_RECEIVED;\ndrivers/scsi/qedi/qedi_fw.c:76:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr, NULL, 0);\ndrivers/scsi/qedi/qedi_fw.c-77-\n--\ndrivers/scsi/qedi/qedi_fw.c=81=static void qedi_process_text_resp(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-140-\ndrivers/scsi/qedi/qedi_fw.c:141:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr_ptr,\ndrivers/scsi/qedi/qedi_fw.c-142-\t\t\t qedi_conn-\u003egen_pdu.resp_buf,\n--\ndrivers/scsi/qedi/qedi_fw.c=148=static void qedi_tmf_resp_work(struct work_struct work)\n--\ndrivers/scsi/qedi/qedi_fw.c-165-\tspin_lock(\u0026session-\u003eback_lock);\ndrivers/scsi/qedi/qedi_fw.c:166:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr_ptr, NULL, 0);\ndrivers/scsi/qedi/qedi_fw.c-167-\tspin_unlock(\u0026session-\u003eback_lock);\n--\ndrivers/scsi/qedi/qedi_fw.c=177=static void qedi_process_tmf_resp(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-249-\ndrivers/scsi/qedi/qedi_fw.c:250:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr_ptr, NULL, 0);\ndrivers/scsi/qedi/qedi_fw.c-251-\tkfree(resp_hdr_ptr);\n--\ndrivers/scsi/qedi/qedi_fw.c=257=static void qedi_process_login_resp(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-306-\ndrivers/scsi/qedi/qedi_fw.c:307:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr_ptr,\ndrivers/scsi/qedi/qedi_fw.c-308-\t\t\t qedi_conn-\u003egen_pdu.resp_buf,\n--\ndrivers/scsi/qedi/qedi_fw.c=408=static int qedi_process_nopin_mesg(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-472-done:\ndrivers/scsi/qedi/qedi_fw.c:473:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr, bdq_data, pdu_len);\ndrivers/scsi/qedi/qedi_fw.c-474-\n--\ndrivers/scsi/qedi/qedi_fw.c=479=static void qedi_process_async_mesg(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-526-\ndrivers/scsi/qedi/qedi_fw.c:527:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )resp_hdr, bdq_data,\ndrivers/scsi/qedi/qedi_fw.c-528-\t\t\t pdu_len);\n--\ndrivers/scsi/qedi/qedi_fw.c=533=static void qedi_process_reject_mesg(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-569-\ndrivers/scsi/qedi/qedi_fw.c:570:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr,\ndrivers/scsi/qedi/qedi_fw.c-571-\t\t\t conn-\u003edata, pld_len);\n--\ndrivers/scsi/qedi/qedi_fw.c=575=static void qedi_scsi_completion(struct qedi_ctx qedi,\n--\ndrivers/scsi/qedi/qedi_fw.c-666-\ndrivers/scsi/qedi/qedi_fw.c:667:\t__iscsi_complete_pdu(conn, (struct iscsi_hdr )hdr,\ndrivers/scsi/qedi/qedi_fw.c-668-\t\t\t conn-\u003edata, datalen);\n--\ninclude/scsi/libiscsi.h=475=extern int iscsi_complete_pdu(struct iscsi_conn , struct iscsi_hdr ,\ninclude/scsi/libiscsi.h-476-\t\t\t char , int);\ninclude/scsi/libiscsi.h:477:extern int __iscsi_complete_pdu(struct iscsi_conn , struct iscsi_hdr ,\ninclude/scsi/libiscsi.h-478-\t\t\t\tchar , int);\n" }
61/3	2026/10/08 05:24	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 25408 output: 40 thoughts: 31 Thoughts: Okay, let's dive into this. Here's my take on understanding `__iscsi_complete_pdu` in `drivers/scsi/libiscsi.c`: Dissecting `__iscsi_complete_pdu` Alright, I'm going to pull up `drivers/scsi/libiscsi.c` and zero in on the `__iscsi_complete_pdu` function. My initial thought is to figure out its precise role within the iSCSI data path. Given the naming convention, the double underscore typically points to a low-level, internal helper, not something exposed directly to higher layers. It's likely a critical piece in the puzzle of processing incoming iSCSI Protocol Data Units (PDUs). I'm betting this function is responsible for the final steps in processing a received PDU. This could involve several things: completing error handling, updating session or connection state, potentially passing the received data or control information up to the SCSI layer, freeing resources, or triggering subsequent actions based on the PDU's content (like a response to a SCSI command). It's probably the end of the line for PDU processing. Knowing the iSCSI protocol, and seeing it is labeled complete, I'd expect it to handle things like checksum validation, sequence number verification, ensuring the PDU's contents are consistent with what's expected in the iSCSI protocol, and notifying the upper layers of data availability or command completion. It may also signal the transport layer to prepare to receive the next PDU. I'll need to check the function's arguments to see exactly what context it receives and manipulates. Essentially, I'm expecting this to be the cleanup crew after the heavy lifting, ensuring everything is as it should be before moving on.
62/3	2026/10/08 05:25	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi.c", "FirstLine": 1210, "LineCount": 90 } Results: { "Contents": "1210:\t * itt must have been called.\n1211:\t /\n1212:\tint __iscsi_complete_pdu(struct iscsi_conn conn, struct iscsi_hdr hdr,\n1213:\t\t\t\t char data, int datalen)\n1214:\t{\n1215:\t\tstruct iscsi_session session = conn-\u003esession;\n1216:\t\tint opcode = hdr-\u003eopcode \u0026 ISCSI_OPCODE_MASK, rc = 0;\n1217:\t\tstruct iscsi_task task;\n1218:\t\tuint32_t itt;\n1219:\t\n1220:\t\tconn-\u003elast_recv = jiffies;\n1221:\t\trc = iscsi_verify_itt(conn, hdr-\u003eitt);\n1222:\t\tif (rc)\n1223:\t\t\treturn rc;\n1224:\t\n1225:\t\tif (hdr-\u003eitt != RESERVED_ITT)\n1226:\t\t\titt = get_itt(hdr-\u003eitt);\n1227:\t\telse\n1228:\t\t\titt = ~0U;\n1229:\t\n1230:\t\tISCSI_DBG_SESSION(session, \"[op 0x%x cid %d itt 0x%x len %d]\\n\",\n1231:\t\t\t\t opcode, conn-\u003eid, itt, datalen);\n1232:\t\n1233:\t\tif (itt == ~0U) {\n1234:\t\t\tiscsi_update_cmdsn(session, (struct iscsi_nopin)hdr);\n1235:\t\n1236:\t\t\tswitch(opcode) {\n1237:\t\t\tcase ISCSI_OP_NOOP_IN:\n1238:\t\t\t\tif (datalen) {\n1239:\t\t\t\t\trc = ISCSI_ERR_PROTO;\n1240:\t\t\t\t\tbreak;\n1241:\t\t\t\t}\n1242:\t\n1243:\t\t\t\tif (hdr-\u003ettt == cpu_to_be32(ISCSI_RESERVED_TAG))\n1244:\t\t\t\t\tbreak;\n1245:\t\n1246:\t\t\t\t/ In RX path we are under back lock /\n1247:\t\t\t\tspin_unlock(\u0026session-\u003eback_lock);\n1248:\t\t\t\tspin_lock(\u0026session-\u003efrwd_lock);\n1249:\t\t\t\tiscsi_send_nopout(conn, (struct iscsi_nopin)hdr);\n1250:\t\t\t\tspin_unlock(\u0026session-\u003efrwd_lock);\n1251:\t\t\t\tspin_lock(\u0026session-\u003eback_lock);\n1252:\t\t\t\tbreak;\n1253:\t\t\tcase ISCSI_OP_REJECT:\n1254:\t\t\t\trc = iscsi_handle_reject(conn, hdr, data, datalen);\n1255:\t\t\t\tbreak;\n1256:\t\t\tcase ISCSI_OP_ASYNC_EVENT:\n1257:\t\t\t\tconn-\u003eexp_statsn = be32_to_cpu(hdr-\u003estatsn) + 1;\n1258:\t\t\t\tif (iscsi_recv_pdu(conn-\u003ecls_conn, hdr, data, datalen))\n1259:\t\t\t\t\trc = ISCSI_ERR_CONN_FAILED;\n1260:\t\t\t\tbreak;\n1261:\t\t\tdefault:\n1262:\t\t\t\trc = ISCSI_ERR_BAD_OPCODE;\n1263:\t\t\t\tbreak;\n1264:\t\t\t}\n1265:\t\t\tgoto out;\n1266:\t\t}\n1267:\t\n1268:\t\tswitch(opcode) {\n1269:\t\tcase ISCSI_OP_SCSI_CMD_RSP:\n1270:\t\tcase ISCSI_OP_SCSI_DATA_IN:\n1271:\t\t\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\n1272:\t\t\tif (!task)\n1273:\t\t\t\treturn ISCSI_ERR_BAD_ITT;\n1274:\t\t\ttask-\u003elast_xfer = jiffies;\n1275:\t\t\tbreak;\n1276:\t\tcase ISCSI_OP_R2T:\n1277:\t\t\t/\n1278:\t\t\t LLD handles R2Ts if they need to.\n1279:\t\t\t */\n1280:\t\t\treturn 0;\n1281:\t\tcase ISCSI_OP_LOGOUT_RSP:\n1282:\t\tcase ISCSI_OP_LOGIN_RSP:\n1283:\t\tcase ISCSI_OP_TEXT_RSP:\n1284:\t\tcase ISCSI_OP_SCSI_TMFUNC_RSP:\n1285:\t\tcase ISCSI_OP_NOOP_IN:\n1286:\t\t\ttask = iscsi_itt_to_task(conn, hdr-\u003eitt);\n1287:\t\t\tif (!task)\n1288:\t\t\t\treturn ISCSI_ERR_BAD_ITT;\n1289:\t\t\tbreak;\n1290:\t\tdefault:\n1291:\t\t\treturn ISCSI_ERR_BAD_OPCODE;\n1292:\t\t}\n1293:\t\n1294:\t\tswitch(opcode) {\n1295:\t\tcase ISCSI_OP_SCSI_CMD_RSP:\n1296:\t\t\tiscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);\n1297:\t\t\tbreak;\n1298:\t\tcase ISCSI_OP_SCSI_DATA_IN:\n1299:\t\t\tiscsi_data_in_rsp(conn, hdr, task);\n" }
63/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 27284 output: 40 thoughts: 29 Thoughts: Okay, here's my summary, taking the role of the expert: Analyzing iSCSI SCSI Command Responses and Data-In Responses Alright, let's dive into this. The key focus here has got to be on how `iscsi_scsi_cmd_rsp` and `iscsi_data_in_rsp` interact, and where the potential bottlenecks or issues might lie in their processing. I need to refresh my memory on the sequence and dependencies. Is the SCSI command response purely a status indication, or does it also carry information that might be crucial for the subsequent `iscsi_data_in_rsp` processing? I'm thinking about error codes, sense data, and how these are handled at different protocol layers. Are we handling them in the most efficient manner? Could there be any timing dependencies between the command and data-in responses that we need to scrutinize? Are we properly handling potential retransmissions or out-of-order arrivals of these packets? I need to consider all possible failure scenarios and edge cases. Let's see if we can find some areas that are not as optimized as they could be, and potentially improve the performance or robustness of the entire iSCSI stack.
64/3	2026/10/08 05:25	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi.c", "FirstLine": 1000, "LineCount": 80 } Results: { "Contents": "1000:\t\n1001:\t\tconn-\u003eexp_statsn = be32_to_cpu(hdr-\u003estatsn) + 1;\n1002:\t\tconn-\u003etmfrsp_pdus_cnt++;\n1003:\t\n1004:\t\tif (session-\u003etmf_state != TMF_QUEUED)\n1005:\t\t\treturn;\n1006:\t\n1007:\t\tif (tmf-\u003eresponse == ISCSI_TMF_RSP_COMPLETE)\n1008:\t\t\tsession-\u003etmf_state = TMF_SUCCESS;\n1009:\t\telse if (tmf-\u003eresponse == ISCSI_TMF_RSP_NO_TASK)\n1010:\t\t\tsession-\u003etmf_state = TMF_NOT_FOUND;\n1011:\t\telse\n1012:\t\t\tsession-\u003etmf_state = TMF_FAILED;\n1013:\t\twake_up(\u0026session-\u003eehwait);\n1014:\t}\n1015:\t\n1016:\tstatic int iscsi_send_nopout(struct iscsi_conn conn, struct iscsi_nopin rhdr)\n1017:\t{\n1018:\t struct iscsi_nopout hdr;\n1019:\t\tstruct iscsi_task task;\n1020:\t\n1021:\t\tif (!rhdr) {\n1022:\t\t\tif (READ_ONCE(conn-\u003eping_task))\n1023:\t\t\t\treturn -EINVAL;\n1024:\t\t}\n1025:\t\n1026:\t\tmemset(\u0026hdr, 0, sizeof(struct iscsi_nopout));\n1027:\t\thdr.opcode = ISCSI_OP_NOOP_OUT \| ISCSI_OP_IMMEDIATE;\n1028:\t\thdr.flags = ISCSI_FLAG_CMD_FINAL;\n1029:\t\n1030:\t\tif (rhdr) {\n1031:\t\t\thdr.lun = rhdr-\u003elun;\n1032:\t\t\thdr.ttt = rhdr-\u003ettt;\n1033:\t\t\thdr.itt = RESERVED_ITT;\n1034:\t\t} else\n1035:\t\t\thdr.ttt = RESERVED_ITT;\n1036:\t\n1037:\t\ttask = iscsi_alloc_mgmt_task(conn, (struct iscsi_hdr )\u0026hdr, NULL, 0);\n1038:\t\tif (!task)\n1039:\t\t\treturn -ENOMEM;\n1040:\t\n1041:\t\tif (!rhdr)\n1042:\t\t\tWRITE_ONCE(conn-\u003eping_task, task);\n1043:\t\n1044:\t\tif (iscsi_send_mgmt_task(task)) {\n1045:\t\t\tif (!rhdr)\n1046:\t\t\t\tWRITE_ONCE(conn-\u003eping_task, NULL);\n1047:\t\t\tiscsi_put_task(task);\n1048:\t\n1049:\t\t\tiscsi_conn_printk(KERN_ERR, conn, \"Could not send nopout\\n\");\n1050:\t\t\treturn -EIO;\n1051:\t\t} else if (!rhdr) {\n1052:\t\t\t/* only track our nops /\n1053:\t\t\tconn-\u003elast_ping = jiffies;\n1054:\t\t}\n1055:\t\n1056:\t\treturn 0;\n1057:\t}\n1058:\t\n1059:\t/\n1060:\t iscsi_nop_out_rsp - SCSI NOP Response processing\n1061:\t * @task: scsi command task\n1062:\t * @nop: the nop structure\n1063:\t * @data: where to put the data\n1064:\t * @datalen: length of data\n1065:\t \n1066:\t iscsi_nop_out_rsp handles nop response from use or\n1067:\t * from user space. called under back_lock\n1068:\t */\n1069:\tstatic int iscsi_nop_out_rsp(struct iscsi_task task,\n1070:\t\t\t\t struct iscsi_nopin nop, char data, int datalen)\n1071:\t{\n1072:\t\tstruct iscsi_conn conn = task-\u003econn;\n1073:\t\tint rc = 0;\n1074:\t\n1075:\t\tif (READ_ONCE(conn-\u003eping_task) != task) {\n1076:\t\t\t/\n1077:\t\t\t * If this is not in response to one of our\n1078:\t\t\t * nops then it must be from userspace.\n1079:\t\t\t */\n" }
65/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 28832 output: 26 thoughts: 16 Thoughts: Okay, here's my attempt at summarizing that thought process, keeping in mind the user is an expert: Finding `iscsi_scsi_cmd_rsp` Alright, let's get down to brass tacks. My initial thought is to zero in on finding `iscsi_scsi_cmd_rsp`. That's the core focus right now. I need to locate where this element fits into the iSCSI SCSI command response flow. I’m thinking, given my familiarity with the iSCSI protocol, and SCSI in general, it's likely a structure, a function, or perhaps even a macro. The specific context will drive my next actions, of course, but that's my starting point. What am I actually looking for? Understanding its exact purpose and location within the code base is paramount to achieving my goals.
66/3	2026/10/08 05:25	tool	grepper	0m Args: { "Expression": "static void iscsi_scsi_cmd_rsp" } Results: { "Output": "drivers/scsi/libiscsi.c=856=EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);\n--\ndrivers/scsi/libiscsi.c-868- */\ndrivers/scsi/libiscsi.c:869:static void iscsi_scsi_cmd_rsp(struct iscsi_conn conn, struct iscsi_hdr hdr,\ndrivers/scsi/libiscsi.c-870-\t\t\t struct iscsi_task task, char *data,\n" }
67/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 29203 output: 39 thoughts: 24 Thoughts: Okay, here's my summary, tailored as if I'm the one thinking it: Diving into libiscsi.c Alright, let's get down to it. I need to refresh my memory on how this iSCSI driver handles a specific scenario. My gut feeling tells me the answer lies somewhere around the `drivers/scsi/libiscsi.c` file, and I'm thinking the relevant code is likely around line 869. That area usually deals with... well, let's see what's actually there before I start jumping to conclusions. Time to pull up the code and get my eyes on it. Hopefully, this refresh will be quick so I can get back to the main problem I'm working on. Let's see what interesting tidbits are hiding in this section of code.
68/3	2026/10/08 05:25	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi.c", "FirstLine": 869, "LineCount": 80 } Results: { "Contents": " 869:\tstatic void iscsi_scsi_cmd_rsp(struct iscsi_conn conn, struct iscsi_hdr hdr,\n 870:\t\t\t\t struct iscsi_task task, char data,\n 871:\t\t\t\t int datalen)\n 872:\t{\n 873:\t\tstruct iscsi_scsi_rsp rhdr = (struct iscsi_scsi_rsp )hdr;\n 874:\t\tstruct iscsi_session session = conn-\u003esession;\n 875:\t\tstruct scsi_cmnd sc = task-\u003esc;\n 876:\t\n 877:\t\tiscsi_update_cmdsn(session, (struct iscsi_nopin)rhdr);\n 878:\t\tconn-\u003eexp_statsn = be32_to_cpu(rhdr-\u003estatsn) + 1;\n 879:\t\n 880:\t\tsc-\u003eresult = (DID_OK \u003c\u003c 16) \| rhdr-\u003ecmd_status;\n 881:\t\n 882:\t\tif (task-\u003eprotected) {\n 883:\t\t\tsector_t sector;\n 884:\t\t\tu8 ascq;\n 885:\t\n 886:\t\t\t/\n 887:\t\t\t Transports that didn't implement check_protection\n 888:\t\t\t * callback but still published T10-PI support to scsi-mid\n 889:\t\t\t * deserve this BUG_ON.\n 890:\t\t\t */\n 891:\t\t\tBUG_ON(!session-\u003ett-\u003echeck_protection);\n 892:\t\n 893:\t\t\tascq = session-\u003ett-\u003echeck_protection(task, \u0026sector);\n 894:\t\t\tif (ascq) {\n 895:\t\t\t\tscsi_build_sense(sc, 1, ILLEGAL_REQUEST, 0x10, ascq);\n 896:\t\t\t\tscsi_set_sense_information(sc-\u003esense_buffer,\n 897:\t\t\t\t\t\t\t SCSI_SENSE_BUFFERSIZE,\n 898:\t\t\t\t\t\t\t sector);\n 899:\t\t\t\tgoto out;\n 900:\t\t\t}\n 901:\t\t}\n 902:\t\n 903:\t\tif (rhdr-\u003eresponse != ISCSI_STATUS_CMD_COMPLETED) {\n 904:\t\t\tsc-\u003eresult = DID_ERROR \u003c\u003c 16;\n 905:\t\t\tgoto out;\n 906:\t\t}\n 907:\t\n 908:\t\tif (rhdr-\u003ecmd_status == SAM_STAT_CHECK_CONDITION) {\n 909:\t\t\tuint16_t senselen;\n 910:\t\n 911:\t\t\tif (datalen \u003c 2) {\n 912:\tinvalid_datalen:\n 913:\t\t\t\tiscsi_conn_printk(KERN_ERR, conn,\n 914:\t\t\t\t\t\t \"Got CHECK_CONDITION but invalid data \"\n 915:\t\t\t\t\t\t \"buffer size of %d\\n\", datalen);\n 916:\t\t\t\tsc-\u003eresult = DID_BAD_TARGET \u003c\u003c 16;\n 917:\t\t\t\tgoto out;\n 918:\t\t\t}\n 919:\t\n 920:\t\t\tsenselen = get_unaligned_be16(data);\n 921:\t\t\tif (datalen \u003c senselen + 2)\n 922:\t\t\t\tgoto invalid_datalen;\n 923:\t\n 924:\t\t\tmemcpy(sc-\u003esense_buffer, data + 2,\n 925:\t\t\t min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));\n 926:\t\t\tISCSI_DBG_SESSION(session, \"copied %d bytes of sense\\n\",\n 927:\t\t\t\t\t min_t(uint16_t, senselen,\n 928:\t\t\t\t\t SCSI_SENSE_BUFFERSIZE));\n 929:\t\t}\n 930:\t\n 931:\t\tif (rhdr-\u003eflags \u0026 (ISCSI_FLAG_CMD_BIDI_UNDERFLOW \|\n 932:\t\t\t\t ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {\n 933:\t\t\tsc-\u003eresult = (DID_BAD_TARGET \u003c\u003c 16) \| rhdr-\u003ecmd_status;\n 934:\t\t}\n 935:\t\n 936:\t\tif (rhdr-\u003eflags \u0026 (ISCSI_FLAG_CMD_UNDERFLOW \|\n 937:\t\t ISCSI_FLAG_CMD_OVERFLOW)) {\n 938:\t\t\tint res_count = be32_to_cpu(rhdr-\u003eresidual_count);\n 939:\t\n 940:\t\t\tif (res_count \u003e 0 \u0026\u0026\n 941:\t\t\t (rhdr-\u003eflags \u0026 ISCSI_FLAG_CMD_OVERFLOW \|\|\n 942:\t\t\t res_count \u003c= scsi_bufflen(sc)))\n 943:\t\t\t\t/ write side for bidi or uni-io set_resid */\n 944:\t\t\t\tscsi_set_resid(sc, res_count);\n 945:\t\t\telse\n 946:\t\t\t\tsc-\u003eresult = (DID_BAD_TARGET \u003c\u003c 16) \| rhdr-\u003ecmd_status;\n 947:\t\t}\n 948:\tout:\n" }
69/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 30780 output: 24 thoughts: 1720 Thoughts: Analyzing the Impact of `iscsi_tcp_zero_unread` on Uninitialized Memory Okay, so I'm diving into this `iscsi_tcp_zero_unread` patch, and my main concern is whether it introduces or exposes any uninitialized memory risks. My focus is entirely on KMSAN, so I need to see if this code introduces scenarios where reads of uninitialized memory are now possible or if existing code paths are altered in a way that allows them to read uninitialized data. Given my expertise, KASAN, LOCKDEP and other standard bug detectors are not my concern here. First, I need to understand what this function is supposed to do. It looks like it's designed to zero out the "unread" portion of a SCSI read buffer in the iSCSI TCP context. This means the target hasn't sent all the data it promised, and the remaining part of the buffer might contain stale or uninitialized data. The goal is to prevent that stale data from being exposed to the caller. Let's break down the patch itself: The code itself appears straightforward: ```c static void iscsi_tcp_zero_unread(struct iscsi_task task) { struct iscsi_tcp_task tcp_task = task->dd_data; struct scsi_cmnd sc = task->sc; if (!sc \|\| sc->sc_data_direction != DMA_FROM_DEVICE \|\| tcp_task->data_in_bytes >= sc->sdb.length) return; sg_zero_buffer(sc->sdb.table.sgl, sc->sdb.table.nents, sc->sdb.length - tcp_task->data_in_bytes, tcp_task->data_in_bytes); } ``` Okay, so it takes a `task` structure as input. It checks to make sure the SCSI command is a read (`DMA_FROM_DEVICE`) and that there's actually unread data. Then, it uses `sg_zero_buffer` to clear the relevant portion of the scatter-gather list buffer. Now, I'm going through the rule list. Let's ask the critical questions: *Does this code read* any potentially uninitialized variables?** The variables read are `task->dd_data`, `task->sc`, `tcp_task->data_in_bytes`, `sc->sdb.length`, `sc->sdb.table.sgl` and `sc->sdb.table.nents`. I need to ensure they are initialized before they're read. `tcp_task->data_in_bytes` is initialized to 0 in `iscsi_tcp_task_init` which is good. * *Could this patch introduce any conditional logic that depends* on uninitialized variables?** Not directly in the code itself, but I need to understand how the parameters passed to this function are handled! * Does this patch change bounds checks, lengths, or logic in a way that allows surrounding code to access uninitialized bytes of existing buffers? This is where I start to get concerned. The core of the function uses subtraction to calculate how much buffer is not read. Is there a scenario where the subtraction could underflow, leading to reading beyond the buffer's allocation? Is there anything that could lead to an incorrect value being passed to `sg_zero_buffer`? Are the assumptions the same in all cases? Now, I need to see where this function is called and with what arguments. Let's see... it's called in `iscsi_tcp_complete_cmd`. Okay, now I need to check where `iscsi_itt_to_ctask` is used to see how `task` is populated. I need to understand what guarantees `iscsi_itt_to_ctask` makes about the `task` structure, especially that `tcp_task` has been properly initialized. Are there any race conditions or conditions under which `sc` can be NULL? Are there any scenarios in which `tcp_task->data_in_bytes` isn't initialized? I need to analyze those code paths!
70/3	2026/10/08 05:25	tool	grepper	0m Args: { "Expression": "iscsi_itt_to_ctask" } Results: { "Output": "drivers/infiniband/ulp/iser/iser_initiator.c=591=static int iser_check_remote_inv(struct iser_conn iser_conn, struct ib_wc wc,\n--\ndrivers/infiniband/ulp/iser/iser_initiator.c-603-\ndrivers/infiniband/ulp/iser/iser_initiator.c:604:\t\ttask = iscsi_itt_to_ctask(iser_conn-\u003eiscsi_conn, hdr-\u003eitt);\ndrivers/infiniband/ulp/iser/iser_initiator.c-605-\t\tif (likely(task)) {\n--\ndrivers/scsi/cxgbi/libcxgbi.c=1508=skb_read_pdu_bhs(struct cxgbi_sock csk, struct iscsi_conn conn,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-1539-\t\titt_t itt = ((struct iscsi_data )skb-\u003edata)-\u003eitt;\ndrivers/scsi/cxgbi/libcxgbi.c:1540:\t\tstruct iscsi_task task = iscsi_itt_to_ctask(conn, itt);\ndrivers/scsi/cxgbi/libcxgbi.c-1541-\t\tu32 data_sn = be32_to_cpu(((struct iscsi_data )\n--\ndrivers/scsi/libiscsi.c=1212=int __iscsi_complete_pdu(struct iscsi_conn conn, struct iscsi_hdr hdr,\n--\ndrivers/scsi/libiscsi.c-1270-\tcase ISCSI_OP_SCSI_DATA_IN:\ndrivers/scsi/libiscsi.c:1271:\t\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\ndrivers/scsi/libiscsi.c-1272-\t\tif (!task)\n--\ndrivers/scsi/libiscsi.c=1395=EXPORT_SYMBOL_GPL(iscsi_verify_itt);\n--\ndrivers/scsi/libiscsi.c-1397-/\ndrivers/scsi/libiscsi.c:1398: iscsi_itt_to_ctask - look up ctask by itt\ndrivers/scsi/libiscsi.c-1399- * @conn: iscsi connection\n--\ndrivers/scsi/libiscsi.c-1405- /\ndrivers/scsi/libiscsi.c:1406:struct iscsi_task iscsi_itt_to_ctask(struct iscsi_conn conn, itt_t itt)\ndrivers/scsi/libiscsi.c-1407-{\n--\ndrivers/scsi/libiscsi.c-1425-}\ndrivers/scsi/libiscsi.c:1426:EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);\ndrivers/scsi/libiscsi.c-1427-\n--\ndrivers/scsi/libiscsi_tcp.c=437=static int iscsi_tcp_complete_cmd(struct iscsi_conn conn, struct iscsi_hdr hdr,\n--\ndrivers/scsi/libiscsi_tcp.c-443-\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\ndrivers/scsi/libiscsi_tcp.c:444:\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\ndrivers/scsi/libiscsi_tcp.c-445-\tif (!task) {\n--\ndrivers/scsi/libiscsi_tcp.c=586=static int iscsi_tcp_r2t_rsp(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-599-\tspin_lock(\u0026session-\u003eback_lock);\ndrivers/scsi/libiscsi_tcp.c:600:\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\ndrivers/scsi/libiscsi_tcp.c-601-\tif (!task) {\n--\ndrivers/scsi/libiscsi_tcp.c=746=iscsi_tcp_hdr_dissect(struct iscsi_conn conn, struct iscsi_hdr hdr)\n--\ndrivers/scsi/libiscsi_tcp.c-777-\t\tspin_lock(\u0026conn-\u003esession-\u003eback_lock);\ndrivers/scsi/libiscsi_tcp.c:778:\t\ttask = iscsi_itt_to_ctask(conn, hdr-\u003eitt);\ndrivers/scsi/libiscsi_tcp.c-779-\t\tif (!task)\n--\ndrivers/scsi/qedi/qedi_fw.c=1312=static void qedi_abort_work(struct work_struct work)\n--\ndrivers/scsi/qedi/qedi_fw.c-1329-\tspin_lock_bh(\u0026conn-\u003esession-\u003eback_lock);\ndrivers/scsi/qedi/qedi_fw.c:1330:\tctask = iscsi_itt_to_ctask(conn, tmf_hdr-\u003ertt);\ndrivers/scsi/qedi/qedi_fw.c-1331-\tif (!ctask) {\n--\ninclude/scsi/libiscsi.h=479=extern int iscsi_verify_itt(struct iscsi_conn , itt_t);\ninclude/scsi/libiscsi.h:480:extern struct iscsi_task iscsi_itt_to_ctask(struct iscsi_conn , itt_t);\ninclude/scsi/libiscsi.h-481-extern struct iscsi_task iscsi_itt_to_task(struct iscsi_conn *, itt_t);\n" }
71/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 34960 output: 40 thoughts: 30 Thoughts: Here's my take on those thoughts, tailored for an expert audience: Diving into the iSCSI ITT Translation Okay, so I need to understand how we're mapping the iSCSI Initiator Task Tag (ITT) to our internal context structure, the `ctask`. The likely place to start is `drivers/scsi/libiscsi.c`. I need to review `iscsi_itt_to_ctask` specifically. I want to see how this function handles the ITT values, how it does the lookup, what data structures it's interacting with, and what kind of error handling or validation is taking place. This is a critical piece, since incorrect or inefficient ITT to ctask mapping can lead to performance bottlenecks, or worse, corrupted data and SCSI target confusion. I also need to be mindful of potential race conditions in a multi-threaded or multi-connection iSCSI environment.
72/3	2026/10/08 05:25	tool	read-file	0m Args: { "File": "drivers/scsi/libiscsi.c", "FirstLine": 1400, "LineCount": 30 } Results: { "Contents": "1400:\t * @itt: itt\n1401:\t \n1402:\t This should be used for cmd tasks.\n1403:\t \n1404:\t The session back_lock must be held.\n1405:\t /\n1406:\tstruct iscsi_task iscsi_itt_to_ctask(struct iscsi_conn conn, itt_t itt)\n1407:\t{\n1408:\t\tstruct iscsi_task task;\n1409:\t\n1410:\t\tif (iscsi_verify_itt(conn, itt))\n1411:\t\t\treturn NULL;\n1412:\t\n1413:\t\ttask = iscsi_itt_to_task(conn, itt);\n1414:\t\tif (!task \|\| !task-\u003esc)\n1415:\t\t\treturn NULL;\n1416:\t\n1417:\t\tif (iscsi_cmd(task-\u003esc)-\u003eage != conn-\u003esession-\u003eage) {\n1418:\t\t\tiscsi_session_printk(KERN_ERR, conn-\u003esession,\n1419:\t\t\t\t\t \"task's session age %d, expected %d\\n\",\n1420:\t\t\t\t\t iscsi_cmd(task-\u003esc)-\u003eage, conn-\u003esession-\u003eage);\n1421:\t\t\treturn NULL;\n1422:\t\t}\n1423:\t\n1424:\t\treturn task;\n1425:\t}\n1426:\tEXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);\n1427:\t\n1428:\tvoid iscsi_session_failure(struct iscsi_session *session,\n1429:\t\t\t\t enum iscsi_err err)\n" }
73/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 35689 output: 25 thoughts: 606 Thoughts: Analyzing the Security Implications of a Scatterlist Zeroing Patch Okay, let's break this down. First, `iscsi_itt_to_ctask` guarantees a non-NULL `task->sc`. Good. Then, in `iscsi_tcp_task_init`, `tcp_task->data_in_bytes = 0`. This is followed by the data arrival check: `if (tcp_task->data_offset != tcp_task->data_in_bytes) return ISCSI_ERR_DATA_OFFSET;` and the increment of `tcp_task->data_in_bytes`. And then we have `iscsi_tcp_zero_unread(task)`. Aha! `sg_zero_buffer` is called to zero out the unread portion of the scatterlist buffer. So, this patch is explicitly zeroing memory in the buffer that wasn't read by the iSCSI target. Why? Because without this, the leftover bytes in the buffer would contain whatever stale data was present, potentially leading to an information leak. It's designed to prevent reading uninitialized or stale memory. Clever! But, here's the critical question: Does this patch itself introduce any uninitialized memory risks? That's what I need to investigate. I need to scrutinize every change. 1. `struct iscsi_tcp_task` now has `uint32_t data_in_bytes;`. Where is this structure allocated? I need to track down how `iscsi_tcp_task` is allocated in the code to ensure it's properly initialized. I need to look for allocations that use the size of this new struct to make sure we don't end up with an uninitialized variable anywhere. I see allocations in `cxgbi_create_session`, `iscsi_sw_tcp_session_create`, `iscsi_pool_init`, and `iscsi_prep_scsi_cmd_pdu`. Okay, I'll grep for `sizeof(struct iscsi_tcp_task)` to see what's happening. I need to make sure this new member is always initialized to 0. It is a good thing that the new member `data_in_bytes` is initialized to 0 in `iscsi_tcp_task_init`. Looks like a net benefit!
74/3	2026/10/08 05:25	tool	grepper	0m Args: { "Expression": "sizeof\$struct iscsi_tcp_task\$" } Results: { "Output": "drivers/scsi/cxgbi/libcxgbi.c=2726=struct iscsi_cls_session cxgbi_create_session(struct iscsi_endpoint ep,\n--\ndrivers/scsi/cxgbi/libcxgbi.c-2748-\t\t\t\t\tcmds_max, 0,\ndrivers/scsi/cxgbi/libcxgbi.c:2749:\t\t\t\t\tsizeof(struct iscsi_tcp_task) +\ndrivers/scsi/cxgbi/libcxgbi.c-2750-\t\t\t\t\tsizeof(struct cxgbi_task_data),\n--\ndrivers/scsi/cxgbi/libcxgbi.h=539=struct cxgbi_task_data {\n--\ndrivers/scsi/cxgbi/libcxgbi.h-555-#define iscsi_task_cxgbi_data(task) \\\ndrivers/scsi/cxgbi/libcxgbi.h:556:\t((task)-\u003edd_data + sizeof(struct iscsi_tcp_task))\ndrivers/scsi/cxgbi/libcxgbi.h-557-\n--\ndrivers/scsi/iscsi_tcp.c=878=iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,\n--\ndrivers/scsi/iscsi_tcp.c-913-\t\t\t\t\t cmds_max, 0,\ndrivers/scsi/iscsi_tcp.c:914:\t\t\t\t\t sizeof(struct iscsi_tcp_task) +\ndrivers/scsi/iscsi_tcp.c-915-\t\t\t\t\t sizeof(struct iscsi_sw_tcp_hdrbuf),\n" }
75/3	2026/10/08 05:25	llm	kmsan-evaluator	0m Model: gemini-3.8-flash Args: null Results: null Tokens: input: 37267 output: 330 thoughts: 2936 Thoughts: KMSAN Assessment: No Need for KMSAN Okay, let's break this down from a memory safety perspective. The patch introduces a `data_in_bytes` field within the `iscsi_tcp_task` structure. This field keeps track of the number of bytes that have been received for a particular SCSI command. It's initialized to zero in `iscsi_tcp_task_init`, which is called when a task is initialized. Critically, this initialization happens before any data is handled for a given ITT. Every time the task is initialized, this value is reset. The core function added, `iscsi_tcp_zero_unread`, utilizes `sg_zero_buffer` to write zeroes into the scatterlist (`sc->sdb.table.sgl`) from the offset of `tcp_task->data_in_bytes` for the remaining length up to the overall command length (`sc->sdb.length`). This step is essential because it initializes the memory that hasn't been written to, preventing stale data from existing in the read buffer. `sg_zero_buffer` uses kernel memory mapping (kmap_atomic, kmap_local_page) and `memset` to ensure zero-initialization. Now, the important part: is there any risk of uninitialized memory being used? The answer is emphatically no. We're explicitly initializing memory to zero. The potential issues here are related to logic errors: out-of-bounds access within `sg_zero_buffer` (due to incorrect offsets, lengths, or scatterlist entries) or locking issues due to interaction with the `back_lock` spinlock, NULL pointer dereferences (e.g., if a task or session structure is invalid), and similar concerns that would be caught by KASAN or LOCKDEP. Let's carefully consider KMSAN's purpose. It's for detecting uninitialized memory reads. This patch actively eliminates the possibility of uninitialized reads. KASAN is already excellent at detecting out-of-bounds accesses, NULL pointer dereferences, and use-after-free bugs. LOCKDEP is designed to catch lock order issues. The checks in `iscsi_tcp_data_in` for `data_offset` validate that offsets don't go out-of-bounds. `sg_zero_buffer` calls like memset also guarantee initialization. This is a crucial distinction: the primary effect of the patch is memory initialization, not introducing uninitialized memory usage. In fact it reduces chances of introducing bugs related to uninitialized variables. Therefore, `NeedsKMSAN=false`. The existing protections offered by KASAN, LOCKDEP, and standard bug detectors are more than sufficient. There are no uninitialized reads or potential info-leaks, thus KMSAN fuzzing would be redundant and wasteful in this case. We're adding code to make the result memory more well-defined (initialized), not less.
76/3	2026/10/08 05:26	tool	set-results	0m Args: { "KMSANReasoning": "The patch introduces logic in the iSCSI TCP transport layer to track the amount of received Data-In bytes (`data_in_bytes`) and zero out the unread remainder of the SCSI command's scatterlist buffer via `sg_zero_buffer()` upon command completion.\n\n1. Uninitialized Memory / KMSAN applicability:\n- The only newly introduced variable is `data_in_bytes` in `struct iscsi_tcp_task`, which is explicitly initialized to 0 in `iscsi_tcp_task_init()`.\n- The patch zeroes out buffer memory (`sg_zero_buffer`) rather than creating uninitialized gaps or leaking uninitialized memory.\n- No uninitialized struct fields, stack allocations, or kernel structures exposed to userspace are introduced or read.\n\n2. KASAN / LOCKDEP applicability:\n- Any risks associated with buffer offsets, lengths passed to `sg_zero_buffer()`, or scatterlist traversal bounds are out-of-bounds access risks, which are directly detected by standard KASAN.\n- Concurrency and lock acquisitions around `session-\u003eback_lock` in `iscsi_tcp_complete_cmd()` are monitored by LOCKDEP.\n- Command task lifecycle and pointer validity (`task`, `task-\u003esc`) are caught by KASAN / standard kernel checks.\n\nBecause the changes do not introduce or expose uninitialized memory risks, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false } Results: { "KMSANReasoning": "The patch introduces logic in the iSCSI TCP transport layer to track the amount of received Data-In bytes (`data_in_bytes`) and zero out the unread remainder of the SCSI command's scatterlist buffer via `sg_zero_buffer()` upon command completion.\n\n1. Uninitialized Memory / KMSAN applicability:\n- The only newly introduced variable is `data_in_bytes` in `struct iscsi_tcp_task`, which is explicitly initialized to 0 in `iscsi_tcp_task_init()`.\n- The patch zeroes out buffer memory (`sg_zero_buffer`) rather than creating uninitialized gaps or leaking uninitialized memory.\n- No uninitialized struct fields, stack allocations, or kernel structures exposed to userspace are introduced or read.\n\n2. KASAN / LOCKDEP applicability:\n- Any risks associated with buffer offsets, lengths passed to `sg_zero_buffer()`, or scatterlist traversal bounds are out-of-bounds access risks, which are directly detected by standard KASAN.\n- Concurrency and lock acquisitions around `session-\u003eback_lock` in `iscsi_tcp_complete_cmd()` are monitored by LOCKDEP.\n- Command task lifecycle and pointer validity (`task`, `task-\u003esc`) are caught by KASAN / standard kernel checks.\n\nBecause the changes do not introduce or expose uninitialized memory risks, a dedicated KMSAN fuzzing session is not warranted.", "NeedsKMSAN": false }

LLM Calls Summary:
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Tool Calls Summary:
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