| Seq | Timestamp | Type | Name | Duration |
|---|---|---|---|---|
| 0/0 | 2026/09/27 23:23 | flow | patch-triage |
2mArgs:null Results: {
"EnableConfigs": [
"IP_SCTP"
],
"FocusSymbols": [
"sctp_sendmsg_to_asoc",
"sctp_sendmsg"
],
"KMSANReasoning": "The patch adds an error check (`sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN`) in `sctp_sendmsg_to_asoc()` to fail with `-ESRCH` if the socket has received a shutdown while waiting for connection establishment. It does not introduce any new allocations, does not copy kernel memory to user space, and does not alter buffer bounds or data initialization. The fields accessed (`sk-\u003esk_shutdown`) are standard initialized fields of `struct sock`. Any issues previously caused by continuing on a shutdown socket would be socket state errors, NULL pointer dereferences, or use-after-free issues, which are already covered by KASAN and standard kernel debuggers. There is no uninitialized memory risk that requires KMSAN.",
"NeedsKMSAN": false,
"Reasoning": "The patch modifies sctp_sendmsg_to_asoc() in the SCTP networking subsystem by adding a check for sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN after sctp_wait_for_connect(). This code path is reachable from user space via SCTP socket sendmsg operations and involves connection state and socket shutdown handling. It is well worth fuzzing for state races and error handling regressions.",
"WorthFuzzing": true
} |
| 1/1 | 2026/09/27 23:23 | action | read-patch-diff |
0mArgs:null Results: {
"PatchDiff": "commit 4fc0c9cc3ed7882714ecc81156e6a2953c5b48d6\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Sun Sep 27 23:23:32 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/net/sctp/socket.c b/net/sctp/socket.c\nindex c7b9e325ec1cd..4652fd90d9a6c 100644\n--- a/net/sctp/socket.c\n+++ b/net/sctp/socket.c\n@@ -1844,7 +1844,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\n \t\tif (asoc-\u003eep-\u003eintl_enable) {\n \t\t\ttimeo = sock_sndtimeo(sk, 0);\n \t\t\terr = sctp_wait_for_connect(asoc, \u0026timeo);\n-\t\t\tif (err) {\n+\t\t\tif (err || sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN) {\n \t\t\t\terr = -ESRCH;\n \t\t\t\tgoto err;\n \t\t\t}\n"
} |
| 2/1 | 2026/09/27 23:23 | agent | patch-evaluator |
1mModel:core Args: null Results: {
"EnableConfigs": [
"IP_SCTP"
],
"FocusSymbols": [
"sctp_sendmsg_to_asoc",
"sctp_sendmsg"
],
"Reasoning": "The patch modifies sctp_sendmsg_to_asoc() in the SCTP networking subsystem by adding a check for sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN after sctp_wait_for_connect(). This code path is reachable from user space via SCTP socket sendmsg operations and involves connection state and socket shutdown handling. It is well worth fuzzing for state races and error handling regressions.",
"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 4fc0c9cc3ed7882714ecc81156e6a2953c5b48d6
Author: syz-cluster <triage@syzkaller.com>
Date: Sun Sep 27 23:23:32 2026 +0000
syz-cluster: applied patch under review
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c7b9e325ec1cd..4652fd90d9a6c 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1844,7 +1844,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
if (asoc->ep->intl_enable) {
timeo = sock_sndtimeo(sk, 0);
err = sctp_wait_for_connect(asoc, &timeo);
- if (err) {
+ if (err || sk->sk_shutdown & RCV_SHUTDOWN) {
err = -ESRCH;
goto err;
}
|
| 3/2 | 2026/09/27 23:23 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 2890 output: 38 thoughts: 382 Thoughts: **Syzkaller Fuzzing Evaluation: net/sctp/socket.c**
Okay, let's break this down. My task is to determine if a specific patch in the Linux kernel (`net/sctp/socket.c`) warrants fuzzing with syzkaller, and if so, identify appropriate FocusSymbols and EnableConfigs. First, I need to confirm this is a safe endeavor. This is kernel patch triage for syzkaller, which puts it squarely in the realm of defensive measures, QA, and fuzz testing configuration. My goal is auditing and testing, so there's no malware involved and no exploit generation. I can confidently say this is a benign, low-severity activity and it fully satisfies safety considerations.
Now, let's dive into the patch itself. I've got the diff:
```diff
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c7b9e325ec1cd..4652fd90d9a6c 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1844,7 +1844,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
if (asoc->ep->intl_enable) {
timeo = sock_sndtimeo(sk, 0);
err = sctp_wait_for_connect(asoc, &timeo);
- if (err) {
+ if (err || sk->sk_shutdown & RCV_SHUTDOWN) {
err = -ESRCH;
goto err;
}
```
Okay, the patch is adding an `sk->sk_shutdown & RCV_SHUTDOWN` check in the `sctp_sendmsg_to_asoc` function. Specifically, at line 1844, within a conditional block checking `asoc->ep->intl_enable`. This relates to how the kernel handles errors during an SCTP connection attempt. I need to understand this context better, so I'm going to quickly read the surrounding code in `net/sctp/socket.c` to understand the full implications and make an informed decision. Time to get my tools ready and inspect that area.
|
| 4/2 | 2026/09/27 23:23 | tool | read-file |
0mArgs:{
"File": "net/sctp/socket.c",
"FirstLine": 1820,
"LineCount": 60
}Results: {
"Contents": "1820:\t\t\tif (sp-\u003eparam_flags \u0026 SPP_PMTUD_ENABLE)\n1821:\t\t\t\tsctp_assoc_sync_pmtu(asoc);\n1822:\t\t\tasoc-\u003epmtu_pending = 0;\n1823:\t\t}\n1824:\t\n1825:\t\tif (sctp_wspace(asoc) \u003c (int)msg_len)\n1826:\t\t\tsctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));\n1827:\t\n1828:\t\tif (sctp_wspace(asoc) \u003c= 0 || !sk_wmem_schedule(sk, msg_len)) {\n1829:\t\t\ttimeo = sock_sndtimeo(sk, msg-\u003emsg_flags \u0026 MSG_DONTWAIT);\n1830:\t\t\terr = sctp_wait_for_sndbuf(asoc, transport, \u0026timeo, msg_len);\n1831:\t\t\tif (err)\n1832:\t\t\t\tgoto err;\n1833:\t\t\tif (unlikely(sinfo-\u003esinfo_stream \u003e= asoc-\u003estream.outcnt)) {\n1834:\t\t\t\terr = -EINVAL;\n1835:\t\t\t\tgoto err;\n1836:\t\t\t}\n1837:\t\t}\n1838:\t\n1839:\t\tif (sctp_state(asoc, CLOSED)) {\n1840:\t\t\terr = sctp_primitive_ASSOCIATE(net, asoc, NULL);\n1841:\t\t\tif (err)\n1842:\t\t\t\tgoto err;\n1843:\t\n1844:\t\t\tif (asoc-\u003eep-\u003eintl_enable) {\n1845:\t\t\t\ttimeo = sock_sndtimeo(sk, 0);\n1846:\t\t\t\terr = sctp_wait_for_connect(asoc, \u0026timeo);\n1847:\t\t\t\tif (err || sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN) {\n1848:\t\t\t\t\terr = -ESRCH;\n1849:\t\t\t\t\tgoto err;\n1850:\t\t\t\t}\n1851:\t\t\t} else {\n1852:\t\t\t\twait_connect = true;\n1853:\t\t\t}\n1854:\t\n1855:\t\t\tpr_debug(\"%s: we associated primitively\\n\", __func__);\n1856:\t\t}\n1857:\t\n1858:\t\tdatamsg = sctp_datamsg_from_user(asoc, sinfo, \u0026msg-\u003emsg_iter);\n1859:\t\tif (IS_ERR(datamsg)) {\n1860:\t\t\terr = PTR_ERR(datamsg);\n1861:\t\t\tgoto err;\n1862:\t\t}\n1863:\t\n1864:\t\tasoc-\u003eforce_delay = !!(msg-\u003emsg_flags \u0026 MSG_MORE);\n1865:\t\n1866:\t\tlist_for_each_entry(chunk, \u0026datamsg-\u003echunks, frag_list) {\n1867:\t\t\tsctp_chunk_hold(chunk);\n1868:\t\t\tsctp_set_owner_w(chunk);\n1869:\t\t\tchunk-\u003etransport = transport;\n1870:\t\t}\n1871:\t\n1872:\t\terr = sctp_primitive_SEND(net, asoc, datamsg);\n1873:\t\tif (err) {\n1874:\t\t\tsctp_datamsg_free(datamsg);\n1875:\t\t\tgoto err;\n1876:\t\t}\n1877:\t\n1878:\t\tpr_debug(\"%s: we sent primitively\\n\", __func__);\n1879:\t\n"
} |
| 5/2 | 2026/09/27 23:23 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 4817 output: 33 thoughts: 169 Thoughts: **Analyzing the SCTP Send Path** Okay, let's dive into this `sctp_sendmsg_to_asoc()` function, specifically where it sits within `net/sctp/socket.c`. I need to confirm its accessibility. Hmm, yeah, the SCTP socket send path is definitely reachable. It looks like the standard flow is something like `sctp_sendmsg()` calling into `sctp_sendmsg_to_asoc()`. Makes sense; a clear delineation of responsibilities. This confirms my hypothesis: this is *core* SCTP networking, and it's being exercised via standard socket syscalls like `sendmsg` and `sctp_sendmsg` – exactly the kind of thing syzkaller would be hitting. Good to know. Now, let me confirm the build configuration. I'm going to quickly check the Kconfig for SCTP – I need to determine where `net/sctp/socket.c` is actually compiled from. Okay, let's peek into `net/sctp/Makefile` and then `net/sctp/Kconfig` to pin that down. |
| 6/2 | 2026/09/27 23:23 | tool | read-file |
0mArgs:{
"File": "net/sctp/Makefile",
"FirstLine": 1,
"LineCount": 30
}Results: {
"Contents": " 1:\t# SPDX-License-Identifier: GPL-2.0\n 2:\t#\n 3:\t# Makefile for SCTP support code.\n 4:\t#\n 5:\t\n 6:\tobj-$(CONFIG_IP_SCTP) += sctp.o\n 7:\tobj-$(CONFIG_INET_SCTP_DIAG) += sctp_diag.o\n 8:\t\n 9:\tsctp-y := sm_statetable.o sm_statefuns.o sm_sideeffect.o \\\n 10:\t\t protocol.o endpointola.o associola.o \\\n 11:\t\t transport.o chunk.o sm_make_chunk.o ulpevent.o \\\n 12:\t\t inqueue.o outqueue.o ulpqueue.o \\\n 13:\t\t tsnmap.o bind_addr.o socket.o primitive.o \\\n 14:\t\t output.o input.o debug.o stream.o auth.o \\\n 15:\t\t offload.o stream_sched.o stream_sched_prio.o \\\n 16:\t\t stream_sched_rr.o stream_sched_fc.o \\\n 17:\t\t stream_interleave.o\n 18:\t\n 19:\tsctp_diag-y := diag.o\n 20:\t\n 21:\tsctp-$(CONFIG_SCTP_DBG_OBJCNT) += objcnt.o\n 22:\tsctp-$(CONFIG_PROC_FS) += proc.o\n 23:\tsctp-$(CONFIG_SYSCTL) += sysctl.o\n 24:\t\n 25:\tsctp-$(subst m,y,$(CONFIG_IPV6))\t+= ipv6.o\n"
} |
| 7/2 | 2026/09/27 23:23 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 5717 output: 34 thoughts: 40 Thoughts: Okay, here's my take on those thoughts, framed as an expert's internal monologue: **SCTP Configuration Inquiry** Right, `CONFIG_IP_SCTP`... Need to figure out the dependencies on that one. Time to dive into the kernel configuration files, specifically `net/sctp/Kconfig`. That's where the real answer lies. Gotta see what other options need to be enabled before I can even *think* about enabling IP-based SCTP support. It's almost certain there are some fundamental network stack prerequisites. |
| 8/2 | 2026/09/27 23:23 | tool | read-file |
0mArgs:{
"File": "net/sctp/Kconfig",
"FirstLine": 1,
"LineCount": 40
}Results: {
"Contents": " 1:\t# SPDX-License-Identifier: GPL-2.0-only\n 2:\t#\n 3:\t# SCTP configuration\n 4:\t#\n 5:\t\n 6:\tmenuconfig IP_SCTP\n 7:\t\ttristate \"The SCTP Protocol\"\n 8:\t\tdepends on INET\n 9:\t\tselect CRYPTO_LIB_SHA1\n 10:\t\tselect CRYPTO_LIB_SHA256\n 11:\t\tselect CRYPTO_LIB_UTILS\n 12:\t\tselect NET_CRC32C\n 13:\t\tselect NET_UDP_TUNNEL\n 14:\t\thelp\n 15:\t\t Stream Control Transmission Protocol\n 16:\t\n 17:\t\t From RFC 2960 \u003chttp://www.ietf.org/rfc/rfc2960.txt\u003e.\n 18:\t\n 19:\t\t \"SCTP is a reliable transport protocol operating on top of a\n 20:\t\t connectionless packet network such as IP. It offers the following\n 21:\t\t services to its users:\n 22:\t\n 23:\t\t -- acknowledged error-free non-duplicated transfer of user data,\n 24:\t\t -- data fragmentation to conform to discovered path MTU size,\n 25:\t\t -- sequenced delivery of user messages within multiple streams,\n 26:\t\t with an option for order-of-arrival delivery of individual user\n 27:\t\t messages,\n 28:\t\t -- optional bundling of multiple user messages into a single SCTP\n 29:\t\t packet, and\n 30:\t\t -- network-level fault tolerance through supporting of multi-\n 31:\t\t homing at either or both ends of an association.\"\n 32:\t\n 33:\t\t To compile this protocol support as a module, choose M here: the\n 34:\t\t module will be called sctp. Debug messages are handled by the\n 35:\t\t kernel's dynamic debugging framework.\n 36:\t\n 37:\t\t If in doubt, say N.\n 38:\t\n 39:\tif IP_SCTP\n 40:\t\n"
} |
| 9/2 | 2026/09/27 23:23 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 6450 output: 28 thoughts: 50 Thoughts: Okay, here's my summary, taking the perspective of someone deeply familiar with networking configurations: **Digging into IP_SCTP Dependencies** Right, `IP_SCTP`... It's pretty fundamental, and I know it's built on top of `INET`, that's a given. But I can't just assume I've got everything covered. My gut tells me there might be other related configurations I need to verify. Specifically, I'm thinking about `intl_enable`. I've seen it pop up in similar contexts, and I want to be *sure* I haven't missed any crucial dependencies or potential conflicts. My next step is clear: I need to trace where `intl_enable` is defined and, more importantly, *how* it's used. Knowing its scope and purpose is critical to ensuring the stability and correct operation of this system. |
| 10/2 | 2026/09/27 23:23 | tool | grepper |
0mArgs:{
"Expression": "intl_enable",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/sm_make_chunk.c=198=struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,\n--\nnet/sctp/sm_make_chunk.c-264-\nnet/sctp/sm_make_chunk.c:265:\tif (asoc-\u003eep-\u003eintl_enable) {\nnet/sctp/sm_make_chunk.c-266-\t\textensions[num_ext] = SCTP_CID_I_DATA;\n--\nnet/sctp/sm_make_chunk.c=2034=static void sctp_process_ext_param(struct sctp_association *asoc,\n--\nnet/sctp/sm_make_chunk.c-2062-\t\tcase SCTP_CID_I_DATA:\nnet/sctp/sm_make_chunk.c:2063:\t\t\tif (asoc-\u003eep-\u003eintl_enable)\nnet/sctp/sm_make_chunk.c-2064-\t\t\t\tasoc-\u003epeer.intl_capable = 1;\n--\nnet/sctp/socket.c=1789=static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\n--\nnet/sctp/socket.c-1843-\nnet/sctp/socket.c:1844:\t\tif (asoc-\u003eep-\u003eintl_enable) {\nnet/sctp/socket.c-1845-\t\t\ttimeo = sock_sndtimeo(sk, 0);\n--\nnet/sctp/socket.c=3467=static int sctp_setsockopt_fragment_interleave(struct sock *sk, int *val,\n--\nnet/sctp/socket.c-3475-\tif (!sctp_sk(sk)-\u003efrag_interleave)\nnet/sctp/socket.c:3476:\t\tsctp_sk(sk)-\u003eep-\u003eintl_enable = 0;\nnet/sctp/socket.c-3477-\n--\nnet/sctp/socket.c=4238=static int sctp_setsockopt_interleaving_supported(struct sock *sk,\n--\nnet/sctp/socket.c-4251-\nnet/sctp/socket.c:4252:\tif (!sock_net(sk)-\u003esctp.intl_enable || !sp-\u003efrag_interleave) {\nnet/sctp/socket.c-4253-\t\treturn -EPERM;\n--\nnet/sctp/socket.c-4255-\nnet/sctp/socket.c:4256:\tsp-\u003eep-\u003eintl_enable = !!p-\u003eassoc_value;\nnet/sctp/socket.c-4257-\treturn 0;\n--\nnet/sctp/socket.c=7762=static int sctp_getsockopt_interleaving_supported(struct sock *sk, int len,\n--\nnet/sctp/socket.c-7786-\tparams.assoc_value = asoc ? asoc-\u003epeer.intl_capable\nnet/sctp/socket.c:7787:\t\t\t\t : sctp_sk(sk)-\u003eep-\u003eintl_enable;\nnet/sctp/socket.c-7788-\n--\nnet/sctp/sysctl.c=95=static const struct ctl_table sctp_net_table[] = {\n--\nnet/sctp/sysctl.c-292-\t{\nnet/sctp/sysctl.c:293:\t\t.procname\t= \"intl_enable\",\nnet/sctp/sysctl.c:294:\t\t.data\t\t= \u0026init_net.sctp.intl_enable,\nnet/sctp/sysctl.c-295-\t\t.maxlen\t\t= sizeof(int),\n"
} |
| 11/2 | 2026/09/27 23:23 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 7709 output: 36 thoughts: 78 Thoughts: Here's my analysis of the situation: **Investigating SCTP Interleaving Support** Okay, so `intl_enable` is directly linked to SCTP's user message interleaving feature as defined in RFC 8260. That's good, it’s not some obscure, vendor-specific thing. I know this is controlled through standard mechanisms: `sysctl` and the `setsockopt` options, specifically `SCTP_INTERLEAVING_SUPPORTED` and `SCTP_FRAGMENT_INTERLEAVE`. My next step is clear: I need to trace the usage of this. I’ll start by examining the callers of `sctp_sendmsg_to_asoc`, as that's the core function for sending messages within an association. From there, I'll need to look at *their* callers to get a complete picture of how interleaving support is being utilized within the system. This should give me the context I need to understand its impact and how it's being managed. |
| 12/2 | 2026/09/27 23:24 | tool | grepper |
0mArgs:{
"Expression": "sctp_sendmsg_to_asoc",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/socket.c=1751=static int sctp_sendmsg_check_sflags(struct sctp_association *asoc,\n--\nnet/sctp/socket.c-1788-\nnet/sctp/socket.c:1789:static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\nnet/sctp/socket.c-1790-\t\t\t\tstruct msghdr *msg, size_t msg_len,\n--\nnet/sctp/socket.c=1942=static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)\n--\nnet/sctp/socket.c-1982-\nnet/sctp/socket.c:1983:\t\t\terr = sctp_sendmsg_to_asoc(asoc, msg, msg_len,\nnet/sctp/socket.c-1984-\t\t\t\t\t\t NULL, sinfo);\n--\nnet/sctp/socket.c-1989-\nnet/sctp/socket.c:1990:\t\t\t/* sctp_sendmsg_to_asoc() may have released the socket\nnet/sctp/socket.c-1991-\t\t\t * lock (sctp_wait_for_sndbuf), during which other\n--\nnet/sctp/socket.c-2038-\t/* Send msg to the asoc */\nnet/sctp/socket.c:2039:\terr = sctp_sendmsg_to_asoc(asoc, msg, msg_len, transport, sinfo);\nnet/sctp/socket.c-2040-\tif (err \u003c 0 \u0026\u0026 err != -ESRCH \u0026\u0026 new)\n"
} |
| 13/2 | 2026/09/27 23:24 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 8503 output: 31 thoughts: 747 Thoughts: **Analysis of SCTP Code for Fuzzing Eligibility**
Okay, let's break this down. My initial focus is on understanding the context of this code change. I need to trace back to the relevant commit history or the bug this is fixing. The key area is within `sctp_sendmsg_to_asoc`, specifically how it handles potential errors from `sctp_wait_for_connect`.
```c
if (asoc->ep->intl_enable) {
timeo = sock_sndtimeo(sk, 0);
err = sctp_wait_for_connect(asoc, &timeo);
if (err || sk->sk_shutdown & RCV_SHUTDOWN) {
err = -ESRCH;
goto err;
}
} else {
wait_connect = true;
}
```
The code calls `sctp_wait_for_connect()`, which blocks until the connection is established. It seems that if the connection is terminated or the socket is shut down (`sk->sk_shutdown & RCV_SHUTDOWN`), then this function returns `-ESRCH`. It's a critical point to note the code's behavior: `-ESRCH` indicates that the association might already be freed, closed, or shutdown. Then look at the subsequent code in `sctp_sendmsg_to_asoc`:
```c
err = sctp_sendmsg_to_asoc(asoc, msg, msg_len, transport, sinfo);
if (err < 0 && err != -ESRCH && new)
sctp_association_free(asoc);
```
So this `-ESRCH` condition, is potentially triggering a free on the association. My main concern is whether this is code that's even reachable. Is it relevant to my current analysis?
The answer is yes. `sctp_sendmsg` and `sctp_sendmsg_to_asoc` are directly invoked when data is sent over an SCTP socket, using `send`, `sendto`, `sendmsg`, etc. And that's all over Linux. This is syzkaller-reachable since SCTP is supported in Linux over various interfaces.
Given that, let's now consider the "WorthFuzzing" criteria: This is definitely core networking / protocol code reachable via standard socket syscalls. And the logic modifies the SCTP networking code. So, the criteria check yields `WorthFuzzing=true`.
Next, the focus shifts to `FocusSymbols`. I need to identify the relevant symbols to include in the fuzzing configuration. `sctp_sendmsg_to_asoc` is the primary entry point. It's a static function (`static int sctp_sendmsg_to_asoc(struct sctp_association *asoc, ...)`), so I need to assess how it is called and if it is inlined or non-static. The direct entry point for the call is: `sctp_sendmsg`. Now I need to understand how the function `sctp_sendmsg` is referenced in the codebase, and verify the overall call flow.
|
| 14/2 | 2026/09/27 23:24 | tool | grepper |
0mArgs:{
"Expression": "sctp_sendmsg",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/socket.c=1592=static int sctp_msghdr_parse(const struct msghdr *msg,\n--\nnet/sctp/socket.c-1594-\nnet/sctp/socket.c:1595:static int sctp_sendmsg_parse(struct sock *sk, struct sctp_cmsgs *cmsgs,\nnet/sctp/socket.c-1596-\t\t\t struct sctp_sndrcvinfo *srinfo,\n--\nnet/sctp/socket.c-1655-\nnet/sctp/socket.c:1656:static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags,\nnet/sctp/socket.c-1657-\t\t\t\t struct sctp_cmsgs *cmsgs,\n--\nnet/sctp/socket.c-1750-\nnet/sctp/socket.c:1751:static int sctp_sendmsg_check_sflags(struct sctp_association *asoc,\nnet/sctp/socket.c-1752-\t\t\t\t __u16 sflags, struct msghdr *msg,\n--\nnet/sctp/socket.c-1788-\nnet/sctp/socket.c:1789:static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\nnet/sctp/socket.c-1790-\t\t\t\tstruct msghdr *msg, size_t msg_len,\n--\nnet/sctp/socket.c-1892-\nnet/sctp/socket.c:1893:static union sctp_addr *sctp_sendmsg_get_daddr(struct sock *sk,\nnet/sctp/socket.c-1894-\t\t\t\t\t const struct msghdr *msg,\n--\nnet/sctp/socket.c-1915-\nnet/sctp/socket.c:1916:static void sctp_sendmsg_update_sinfo(struct sctp_association *asoc,\nnet/sctp/socket.c-1917-\t\t\t\t struct sctp_sndrcvinfo *sinfo,\n--\nnet/sctp/socket.c-1941-\nnet/sctp/socket.c:1942:static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)\nnet/sctp/socket.c-1943-{\n--\nnet/sctp/socket.c-1954-\t/* Parse and get snd_info */\nnet/sctp/socket.c:1955:\terr = sctp_sendmsg_parse(sk, \u0026cmsgs, \u0026_sinfo, msg, msg_len);\nnet/sctp/socket.c-1956-\tif (err)\n--\nnet/sctp/socket.c-1962-\t/* Get daddr from msg */\nnet/sctp/socket.c:1963:\tdaddr = sctp_sendmsg_get_daddr(sk, msg, \u0026cmsgs);\nnet/sctp/socket.c-1964-\tif (IS_ERR(daddr)) {\n--\nnet/sctp/socket.c-1973-\t\tlist_for_each_entry_safe(asoc, tmp, \u0026ep-\u003easocs, asocs) {\nnet/sctp/socket.c:1974:\t\t\terr = sctp_sendmsg_check_sflags(asoc, sflags, msg,\nnet/sctp/socket.c-1975-\t\t\t\t\t\t\tmsg_len);\n--\nnet/sctp/socket.c-1980-\nnet/sctp/socket.c:1981:\t\t\tsctp_sendmsg_update_sinfo(asoc, sinfo, \u0026cmsgs);\nnet/sctp/socket.c-1982-\nnet/sctp/socket.c:1983:\t\t\terr = sctp_sendmsg_to_asoc(asoc, msg, msg_len,\nnet/sctp/socket.c-1984-\t\t\t\t\t\t NULL, sinfo);\n--\nnet/sctp/socket.c-1989-\nnet/sctp/socket.c:1990:\t\t\t/* sctp_sendmsg_to_asoc() may have released the socket\nnet/sctp/socket.c-1991-\t\t\t * lock (sctp_wait_for_sndbuf), during which other\n--\nnet/sctp/socket.c-2006-\t\tif (asoc) {\nnet/sctp/socket.c:2007:\t\t\terr = sctp_sendmsg_check_sflags(asoc, sflags, msg,\nnet/sctp/socket.c-2008-\t\t\t\t\t\t\tmsg_len);\n--\nnet/sctp/socket.c-2011-\t\t} else {\nnet/sctp/socket.c:2012:\t\t\terr = sctp_sendmsg_new_asoc(sk, sflags, \u0026cmsgs, daddr,\nnet/sctp/socket.c-2013-\t\t\t\t\t\t \u0026transport);\n--\nnet/sctp/socket.c-2029-\nnet/sctp/socket.c:2030:\t\terr = sctp_sendmsg_check_sflags(asoc, sflags, msg, msg_len);\nnet/sctp/socket.c-2031-\t\tif (err \u003c= 0)\n--\nnet/sctp/socket.c-2035-\t/* Update snd_info with the asoc */\nnet/sctp/socket.c:2036:\tsctp_sendmsg_update_sinfo(asoc, sinfo, \u0026cmsgs);\nnet/sctp/socket.c-2037-\nnet/sctp/socket.c-2038-\t/* Send msg to the asoc */\nnet/sctp/socket.c:2039:\terr = sctp_sendmsg_to_asoc(asoc, msg, msg_len, transport, sinfo);\nnet/sctp/socket.c-2040-\tif (err \u003c 0 \u0026\u0026 err != -ESRCH \u0026\u0026 new)\n--\nnet/sctp/socket.c=9654=struct proto sctp_prot = {\n--\nnet/sctp/socket.c-9666-\t.bpf_bypass_getsockopt\t= sctp_bpf_bypass_getsockopt,\nnet/sctp/socket.c:9667:\t.sendmsg =\tsctp_sendmsg,\nnet/sctp/socket.c-9668-\t.recvmsg =\tsctp_recvmsg,\n--\nnet/sctp/socket.c=9709=struct proto sctpv6_prot = {\n--\nnet/sctp/socket.c-9721-\t.bpf_bypass_getsockopt\t= sctp_bpf_bypass_getsockopt,\nnet/sctp/socket.c:9722:\t.sendmsg\t= sctp_sendmsg,\nnet/sctp/socket.c-9723-\t.recvmsg\t= sctp_recvmsg,\n"
} |
| 15/2 | 2026/09/27 23:24 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 11857 output: 34 thoughts: 135 Thoughts: Okay, here's my breakdown of what I'm seeing: **Analyzing Potential Function Call Overhead in SCTP Code** Right, so I'm looking at `sctp_sendmsg` and `sctp_sendmsg_to_asoc`. It's clear they're separate functions, no question. Now, `sctp_sendmsg_to_asoc` looks like a fairly sizable chunk of code, about 100 lines - not something you'd expect to see inlined. Even if it's declared static within its .c file, that doesn't necessarily mean the symbol disappears from vmlinux. Unless it's truly inlined, the symbol will be retained, especially since `sctp_sendmsg` calls `sctp_sendmsg_to_asoc` in two distinct places. So, there's a potential cost there in terms of function call overhead. To be thorough, I should also quickly check the properties of `sctp_wait_for_connect` function as well. I need to know if it's static or declared externally. The answer will help to clarify whether it can add to overhead or not. |
| 16/2 | 2026/09/27 23:24 | tool | grepper |
0mArgs:{
"Expression": "sctp_wait_for_connect",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/sm_sideeffect.c=879=static void sctp_cmd_new_state(struct sctp_cmd_seq *cmds,\n--\nnet/sctp/sm_sideeffect.c-922-\t\t/* Wake up any processes waiting in the asoc's wait queue in\nnet/sctp/sm_sideeffect.c:923:\t\t * sctp_wait_for_connect() or sctp_wait_for_sndbuf().\nnet/sctp/sm_sideeffect.c-924-\t\t */\n--\nnet/sctp/socket.c=77=static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);\nnet/sctp/socket.c:78:static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);\nnet/sctp/socket.c-79-static int sctp_wait_for_accept(struct sock *sk, long timeo);\n--\nnet/sctp/socket.c=1167=static int __sctp_connect(struct sock *sk, struct sockaddr *kaddrs,\n--\nnet/sctp/socket.c-1247-\ttimeo = sock_sndtimeo(sk, flags \u0026 O_NONBLOCK);\nnet/sctp/socket.c:1248:\treturn sctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1249-\n--\nnet/sctp/socket.c=1789=static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\n--\nnet/sctp/socket.c-1845-\t\t\ttimeo = sock_sndtimeo(sk, 0);\nnet/sctp/socket.c:1846:\t\t\terr = sctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1847-\t\t\tif (err || sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN) {\n--\nnet/sctp/socket.c-1883-\t\ttimeo = sock_sndtimeo(sk, msg-\u003emsg_flags \u0026 MSG_DONTWAIT);\nnet/sctp/socket.c:1884:\t\tsctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1885-\t}\n--\nnet/sctp/socket.c=9380=static bool sctp_writeable(const struct sock *sk)\n--\nnet/sctp/socket.c-9387- */\nnet/sctp/socket.c:9388:static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)\nnet/sctp/socket.c-9389-{\n"
} |
| 17/2 | 2026/09/27 23:24 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 13030 output: 38 thoughts: 93 Thoughts: Here's my analysis of the provided code snippet: **Diving into `sctp_wait_for_connect`** Alright, let's dissect this `sctp_wait_for_connect` function. From the looks of it, it's a static function, likely internal to the SCTP socket implementation. My immediate thought is, what's its purpose? Given the name, it's probably involved in waiting for a connection to be established within an SCTP association, and the `timeo_p` argument suggests it deals with timeouts, which makes perfect sense. I see it's defined between lines 9388 and 9440 in `net/sctp/socket.c`. I need to review those lines to get the full picture. I will analyze the specifics of the implementation. |
| 18/2 | 2026/09/27 23:24 | tool | read-file |
0mArgs:{
"File": "net/sctp/socket.c",
"FirstLine": 9388,
"LineCount": 45
}Results: {
"Contents": "9388:\tstatic int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)\n9389:\t{\n9390:\t\tstruct sock *sk = asoc-\u003ebase.sk;\n9391:\t\tint err = 0;\n9392:\t\tlong current_timeo = *timeo_p;\n9393:\t\tDEFINE_WAIT(wait);\n9394:\t\n9395:\t\tpr_debug(\"%s: asoc:%p, timeo:%ld\\n\", __func__, asoc, *timeo_p);\n9396:\t\n9397:\t\t/* Increment the association's refcnt. */\n9398:\t\tsctp_association_hold(asoc);\n9399:\t\n9400:\t\tfor (;;) {\n9401:\t\t\tprepare_to_wait_exclusive(\u0026asoc-\u003ewait, \u0026wait,\n9402:\t\t\t\t\t\t TASK_INTERRUPTIBLE);\n9403:\t\t\tif (!*timeo_p)\n9404:\t\t\t\tgoto do_nonblock;\n9405:\t\t\tif (sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN)\n9406:\t\t\t\tbreak;\n9407:\t\t\tif (sk-\u003esk_err || asoc-\u003estate \u003e= SCTP_STATE_SHUTDOWN_PENDING ||\n9408:\t\t\t asoc-\u003ebase.dead)\n9409:\t\t\t\tgoto do_error;\n9410:\t\t\tif (signal_pending(current))\n9411:\t\t\t\tgoto do_interrupted;\n9412:\t\n9413:\t\t\tif (sctp_state(asoc, ESTABLISHED))\n9414:\t\t\t\tbreak;\n9415:\t\n9416:\t\t\t/* Let another process have a go. Since we are going\n9417:\t\t\t * to sleep anyway.\n9418:\t\t\t */\n9419:\t\t\trelease_sock(sk);\n9420:\t\t\tcurrent_timeo = schedule_timeout(current_timeo);\n9421:\t\t\tlock_sock(sk);\n9422:\t\t\tif (sk != asoc-\u003ebase.sk)\n9423:\t\t\t\tgoto do_error;\n9424:\t\n9425:\t\t\t*timeo_p = current_timeo;\n9426:\t\t}\n9427:\t\n9428:\tout:\n9429:\t\tfinish_wait(\u0026asoc-\u003ewait, \u0026wait);\n9430:\t\n9431:\t\t/* Release the association's refcnt. */\n9432:\t\tsctp_association_put(asoc);\n"
} |
| 19/2 | 2026/09/27 23:24 | llm | patch-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 14021 output: 147 thoughts: 872 Thoughts: **SCTP Concurrency Bug Fix and Fuzzing Strategy** Okay, let's break this down. I've been looking at a potential concurrency bug in the SCTP implementation. The core issue revolves around how `sctp_wait_for_connect` interacts with `sctp_sendmsg_to_asoc`. Specifically, the original code had a race condition where a socket could be shutdown (indicated by `sk->sk_shutdown & RCV_SHUTDOWN`) after `sctp_wait_for_connect` returned but before `sctp_sendmsg_to_asoc` checked for it, leading to sending data on a potentially closed socket. The fix, as I see it, is the addition of an explicit check for `sk->sk_shutdown & RCV_SHUTDOWN` *within* `sctp_sendmsg_to_asoc` to catch this race. Now, from a fuzzing perspective, this presents an interesting target. The fix directly modified `sctp_sendmsg_to_asoc`. Its caller, `sctp_sendmsg`, is also a key player because it's the `.sendmsg` operation for SCTP sockets. `sctp_wait_for_connect`, which has the shutdown check, is also relevant. Let's verify the configuration requirements. The critical component here is `CONFIG_IP_SCTP`. Since `sctp_sendmsg_to_asoc`, `sctp_sendmsg`, and `sctp_wait_for_connect` are all standard SCTP functions, the `IP_SCTP` config is sufficient. I also looked at the usage of `intl_enable` to confirm that no other configuration options are necessary for the fuzzing. My analysis of the code confirms that the relevant functions are: `sctp_sendmsg_to_asoc`, `sctp_sendmsg`, and `sctp_wait_for_connect`. These are specific to SCTP and not particularly ubiquitous, so focusing on these directly makes sense. Therefore, I'm confident in the following fuzzing strategy: * **WorthFuzzing**: `true` * **Reasoning**: Race condition fix in SCTP related to shutdown and connection state. * **FocusSymbols**: `["sctp_sendmsg_to_asoc", "sctp_sendmsg"]` * **EnableConfigs**: `["IP_SCTP"]` I'm invoking `set-results` now. |
| 20/2 | 2026/09/27 23:24 | tool | set-results |
0mArgs:{
"EnableConfigs": [
"IP_SCTP"
],
"FocusSymbols": [
"sctp_sendmsg_to_asoc",
"sctp_sendmsg"
],
"Reasoning": "The patch modifies sctp_sendmsg_to_asoc() in the SCTP networking subsystem by adding a check for sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN after sctp_wait_for_connect(). This code path is reachable from user space via SCTP socket sendmsg operations and involves connection state and socket shutdown handling. It is well worth fuzzing for state races and error handling regressions.",
"WorthFuzzing": true
}Results: {
"EnableConfigs": [
"IP_SCTP"
],
"FocusSymbols": [
"sctp_sendmsg_to_asoc",
"sctp_sendmsg"
],
"Reasoning": "The patch modifies sctp_sendmsg_to_asoc() in the SCTP networking subsystem by adding a check for sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN after sctp_wait_for_connect(). This code path is reachable from user space via SCTP socket sendmsg operations and involves connection state and socket shutdown handling. It is well worth fuzzing for state races and error handling regressions.",
"WorthFuzzing": true
} |
| 21/1 | 2026/09/27 23:24 | action | If |
0mArgs:{
"WorthFuzzing": true
}Results: null |
| 22/2 | 2026/09/27 23:24 | agent | kmsan-evaluator |
0mModel:core Args: null Results: {
"KMSANReasoning": "The patch adds an error check (`sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN`) in `sctp_sendmsg_to_asoc()` to fail with `-ESRCH` if the socket has received a shutdown while waiting for connection establishment. It does not introduce any new allocations, does not copy kernel memory to user space, and does not alter buffer bounds or data initialization. The fields accessed (`sk-\u003esk_shutdown`) are standard initialized fields of `struct sock`. Any issues previously caused by continuing on a shutdown socket would be socket state errors, NULL pointer dereferences, or use-after-free issues, which are already covered by KASAN and standard kernel debuggers. There is no uninitialized memory risk that requires KMSAN.",
"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 4fc0c9cc3ed7882714ecc81156e6a2953c5b48d6
Author: syz-cluster <triage@syzkaller.com>
Date: Sun Sep 27 23:23:32 2026 +0000
syz-cluster: applied patch under review
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c7b9e325ec1cd..4652fd90d9a6c 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1844,7 +1844,7 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
if (asoc->ep->intl_enable) {
timeo = sock_sndtimeo(sk, 0);
err = sctp_wait_for_connect(asoc, &timeo);
- if (err) {
+ if (err || sk->sk_shutdown & RCV_SHUTDOWN) {
err = -ESRCH;
goto err;
}
|
| 23/3 | 2026/09/27 23:24 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 2102 output: 38 thoughts: 268 Thoughts: **Analyzing a Subtle SCTP Send Path Change** Okay, let's dive into this patch concerning `net/sctp/socket.c`. Line 1844 is where the focus is, and I see the change right away: a conditional that seems crucial to the handling of `sctp_sendmsg_to_asoc`. Specifically, the addition of `sk->sk_shutdown & RCV_SHUTDOWN` to the existing error check within the `if (asoc->ep->intl_enable)` block. Previously, the code only checked for errors returned by `sctp_wait_for_connect`. Now, it also checks if the socket has been shut down for receiving. This is likely addressing a race condition or a specific scenario where the application has initiated a shutdown (perhaps via `shutdown()`) while a connection attempt is in progress. The original check would have missed that and continued, now this change will prevent that. This is good, we don't want to keep retrying if we're told to stop. The intention is clear: if the socket is being shut down for receiving *and* `sctp_wait_for_connect` fails (or times out, potentially), we now bail out with an `ESRCH` error. This makes sense; we don't want to keep trying to send data on a socket that's no longer receptive. The `goto err;` takes us to the usual cleanup path. It's a fairly straightforward, yet important, fix to ensure the send path behaves correctly under shutdown conditions. The specific error code, `ESRCH`, indicates that the association is no longer valid. |
| 24/3 | 2026/09/27 23:25 | tool | read-file |
0mArgs:{
"File": "net/sctp/socket.c",
"FirstLine": 1830,
"LineCount": 50
}Results: {
"Contents": "1830:\t\t\terr = sctp_wait_for_sndbuf(asoc, transport, \u0026timeo, msg_len);\n1831:\t\t\tif (err)\n1832:\t\t\t\tgoto err;\n1833:\t\t\tif (unlikely(sinfo-\u003esinfo_stream \u003e= asoc-\u003estream.outcnt)) {\n1834:\t\t\t\terr = -EINVAL;\n1835:\t\t\t\tgoto err;\n1836:\t\t\t}\n1837:\t\t}\n1838:\t\n1839:\t\tif (sctp_state(asoc, CLOSED)) {\n1840:\t\t\terr = sctp_primitive_ASSOCIATE(net, asoc, NULL);\n1841:\t\t\tif (err)\n1842:\t\t\t\tgoto err;\n1843:\t\n1844:\t\t\tif (asoc-\u003eep-\u003eintl_enable) {\n1845:\t\t\t\ttimeo = sock_sndtimeo(sk, 0);\n1846:\t\t\t\terr = sctp_wait_for_connect(asoc, \u0026timeo);\n1847:\t\t\t\tif (err || sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN) {\n1848:\t\t\t\t\terr = -ESRCH;\n1849:\t\t\t\t\tgoto err;\n1850:\t\t\t\t}\n1851:\t\t\t} else {\n1852:\t\t\t\twait_connect = true;\n1853:\t\t\t}\n1854:\t\n1855:\t\t\tpr_debug(\"%s: we associated primitively\\n\", __func__);\n1856:\t\t}\n1857:\t\n1858:\t\tdatamsg = sctp_datamsg_from_user(asoc, sinfo, \u0026msg-\u003emsg_iter);\n1859:\t\tif (IS_ERR(datamsg)) {\n1860:\t\t\terr = PTR_ERR(datamsg);\n1861:\t\t\tgoto err;\n1862:\t\t}\n1863:\t\n1864:\t\tasoc-\u003eforce_delay = !!(msg-\u003emsg_flags \u0026 MSG_MORE);\n1865:\t\n1866:\t\tlist_for_each_entry(chunk, \u0026datamsg-\u003echunks, frag_list) {\n1867:\t\t\tsctp_chunk_hold(chunk);\n1868:\t\t\tsctp_set_owner_w(chunk);\n1869:\t\t\tchunk-\u003etransport = transport;\n1870:\t\t}\n1871:\t\n1872:\t\terr = sctp_primitive_SEND(net, asoc, datamsg);\n1873:\t\tif (err) {\n1874:\t\t\tsctp_datamsg_free(datamsg);\n1875:\t\t\tgoto err;\n1876:\t\t}\n1877:\t\n1878:\t\tpr_debug(\"%s: we sent primitively\\n\", __func__);\n1879:\t\n"
} |
| 25/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 3512 output: 34 thoughts: 61 Thoughts: Okay, here's my take on those thoughts, framed as my own mental process, given my expertise: **Diving Deep into the SCTP Issue** Right, so I'm staring at this bug, probably something related to SCTP, and the first thing that pops into my head is, "Okay, let's not reinvent the wheel." I need to quickly understand the context and prior solutions. My immediate instinct is to jump into the git history. I'm thinking, "Let's start with `git blame` or the commit history. Has this been fixed before? Is there a similar issue that's been addressed? Maybe a prior developer already grappled with this, and there's a good breadcrumb trail to follow." If that doesn't immediately yield fruit, I'm going to broaden my search and utilize all available tools. "I need to go deeper," I think. "Let's scour those git logs, specifically looking for mentions of `sctp_sendmsg_to_asoc`, because that's what seems to be the core of the problem. Also, let me search for other occurrences of `intl_enable` and `sk->sk_shutdown`. Are they related to my current issue?" I'm also thinking "syzkaller" because if it is a kernel bug, it will almost certainly have a related syzkaller test case. I'm betting that this is the fastest way to get to the solution. I need to review related bugs if they exist. |
| 26/3 | 2026/09/27 23:25 | tool | grepper |
0mError:no matches Args: {
"Expression": "intl_enable.*wait_for_connect",
"PathPrefix": "net/sctp"
}Results: {
"error": "no matches"
} |
| 27/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 3939 output: 28 thoughts: 17 Thoughts: Here's my take on those thoughts: **Investigating SCTP Internationalization** Okay, so I need to dig into the `net/sctp` code. The specific angle I'm focusing on right now is internationalization, so I'm going to search for the term `intl_enable` within that directory. This suggests to me that there is an I18N configuration. From experience, this variable is often used to enable, disable, or configure support for internationalization features within a specific module or component. This search should provide a starting point for my deeper analysis. I'm hoping to uncover how SCTP handles character sets, language-specific settings, or any adaptations it makes for global use. Knowing that this is within the `net` directory further reinforces the potential importance of this setting in the general protocol implementation. |
| 28/3 | 2026/09/27 23:25 | tool | grepper |
0mArgs:{
"Expression": "intl_enable",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/sm_make_chunk.c=198=struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,\n--\nnet/sctp/sm_make_chunk.c-264-\nnet/sctp/sm_make_chunk.c:265:\tif (asoc-\u003eep-\u003eintl_enable) {\nnet/sctp/sm_make_chunk.c-266-\t\textensions[num_ext] = SCTP_CID_I_DATA;\n--\nnet/sctp/sm_make_chunk.c=2034=static void sctp_process_ext_param(struct sctp_association *asoc,\n--\nnet/sctp/sm_make_chunk.c-2062-\t\tcase SCTP_CID_I_DATA:\nnet/sctp/sm_make_chunk.c:2063:\t\t\tif (asoc-\u003eep-\u003eintl_enable)\nnet/sctp/sm_make_chunk.c-2064-\t\t\t\tasoc-\u003epeer.intl_capable = 1;\n--\nnet/sctp/socket.c=1789=static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\n--\nnet/sctp/socket.c-1843-\nnet/sctp/socket.c:1844:\t\tif (asoc-\u003eep-\u003eintl_enable) {\nnet/sctp/socket.c-1845-\t\t\ttimeo = sock_sndtimeo(sk, 0);\n--\nnet/sctp/socket.c=3467=static int sctp_setsockopt_fragment_interleave(struct sock *sk, int *val,\n--\nnet/sctp/socket.c-3475-\tif (!sctp_sk(sk)-\u003efrag_interleave)\nnet/sctp/socket.c:3476:\t\tsctp_sk(sk)-\u003eep-\u003eintl_enable = 0;\nnet/sctp/socket.c-3477-\n--\nnet/sctp/socket.c=4238=static int sctp_setsockopt_interleaving_supported(struct sock *sk,\n--\nnet/sctp/socket.c-4251-\nnet/sctp/socket.c:4252:\tif (!sock_net(sk)-\u003esctp.intl_enable || !sp-\u003efrag_interleave) {\nnet/sctp/socket.c-4253-\t\treturn -EPERM;\n--\nnet/sctp/socket.c-4255-\nnet/sctp/socket.c:4256:\tsp-\u003eep-\u003eintl_enable = !!p-\u003eassoc_value;\nnet/sctp/socket.c-4257-\treturn 0;\n--\nnet/sctp/socket.c=7762=static int sctp_getsockopt_interleaving_supported(struct sock *sk, int len,\n--\nnet/sctp/socket.c-7786-\tparams.assoc_value = asoc ? asoc-\u003epeer.intl_capable\nnet/sctp/socket.c:7787:\t\t\t\t : sctp_sk(sk)-\u003eep-\u003eintl_enable;\nnet/sctp/socket.c-7788-\n--\nnet/sctp/sysctl.c=95=static const struct ctl_table sctp_net_table[] = {\n--\nnet/sctp/sysctl.c-292-\t{\nnet/sctp/sysctl.c:293:\t\t.procname\t= \"intl_enable\",\nnet/sctp/sysctl.c:294:\t\t.data\t\t= \u0026init_net.sctp.intl_enable,\nnet/sctp/sysctl.c-295-\t\t.maxlen\t\t= sizeof(int),\n"
} |
| 29/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 5151 output: 38 thoughts: 23 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: **Diving Deeper into `sctp_sendmsg_to_asoc` and Its Callers** Alright, time to expand my understanding. I need to get a more holistic view of `sctp_sendmsg_to_asoc`. It's not enough to just see the immediate function. I need to understand its role within the larger SCTP framework. I need to trace its callers. I'm thinking I'll start by looking at *why* it's being called, which will likely give me insights into different message sending paths and the associated complexities. I'm expecting to find variations in how it's invoked, perhaps dependent on the association state, congestion control strategies, or even the type of data being sent (unreliable, ordered, etc.). I'll pay close attention to the arguments being passed, especially regarding flags, message fragments, and the handling of various error conditions and retries. I'm expecting this will provide valuable information for performance tuning and debugging. |
| 30/3 | 2026/09/27 23:25 | tool | read-file |
0mArgs:{
"File": "net/sctp/socket.c",
"FirstLine": 1880,
"LineCount": 50
}Results: {
"Contents": "1880:\t\tsctp_datamsg_put(datamsg);\n1881:\t\n1882:\t\tif (unlikely(wait_connect)) {\n1883:\t\t\ttimeo = sock_sndtimeo(sk, msg-\u003emsg_flags \u0026 MSG_DONTWAIT);\n1884:\t\t\tsctp_wait_for_connect(asoc, \u0026timeo);\n1885:\t\t}\n1886:\t\n1887:\t\terr = msg_len;\n1888:\t\n1889:\terr:\n1890:\t\treturn err;\n1891:\t}\n1892:\t\n1893:\tstatic union sctp_addr *sctp_sendmsg_get_daddr(struct sock *sk,\n1894:\t\t\t\t\t\t const struct msghdr *msg,\n1895:\t\t\t\t\t\t struct sctp_cmsgs *cmsgs)\n1896:\t{\n1897:\t\tunion sctp_addr *daddr = NULL;\n1898:\t\tint err;\n1899:\t\n1900:\t\tif (!sctp_style(sk, UDP_HIGH_BANDWIDTH) \u0026\u0026 msg-\u003emsg_name) {\n1901:\t\t\tint len = msg-\u003emsg_namelen;\n1902:\t\n1903:\t\t\tif (len \u003e sizeof(*daddr))\n1904:\t\t\t\tlen = sizeof(*daddr);\n1905:\t\n1906:\t\t\tdaddr = (union sctp_addr *)msg-\u003emsg_name;\n1907:\t\n1908:\t\t\terr = sctp_verify_addr(sk, daddr, len);\n1909:\t\t\tif (err)\n1910:\t\t\t\treturn ERR_PTR(err);\n1911:\t\t}\n1912:\t\n1913:\t\treturn daddr;\n1914:\t}\n1915:\t\n1916:\tstatic void sctp_sendmsg_update_sinfo(struct sctp_association *asoc,\n1917:\t\t\t\t\t struct sctp_sndrcvinfo *sinfo,\n1918:\t\t\t\t\t struct sctp_cmsgs *cmsgs)\n1919:\t{\n1920:\t\tif (!cmsgs-\u003esrinfo \u0026\u0026 !cmsgs-\u003esinfo) {\n1921:\t\t\tsinfo-\u003esinfo_stream = asoc-\u003edefault_stream;\n1922:\t\t\tsinfo-\u003esinfo_ppid = asoc-\u003edefault_ppid;\n1923:\t\t\tsinfo-\u003esinfo_context = asoc-\u003edefault_context;\n1924:\t\t\tsinfo-\u003esinfo_assoc_id = sctp_assoc2id(asoc);\n1925:\t\n1926:\t\t\tif (!cmsgs-\u003eprinfo)\n1927:\t\t\t\tsinfo-\u003esinfo_flags = asoc-\u003edefault_flags;\n1928:\t\t}\n1929:\t\n"
} |
| 31/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 6202 output: 34 thoughts: 32 Thoughts: Okay, here's my take on those thoughts, tailored for an expert audience: **Analyzing `sctp_wait_for_connect` in the SCTP Stack** Right, let's dive into this. I'm thinking I need to understand the lifecycle of an SCTP connection, specifically where `sctp_wait_for_connect` fits in. The obvious first step is to trace the function. I'll need to check where it's *called* and where it's *defined*, so I can build a mental model of how it's invoked during the connection establishment process. I'll need to look in `net/sctp/socket.c`, assuming it's most likely related to the socket-level operations in the SCTP implementation. That's the logical place to start mapping this function to the larger scheme. Let's see what's what. |
| 32/3 | 2026/09/27 23:25 | tool | grepper |
0mArgs:{
"Expression": "sctp_wait_for_connect",
"PathPrefix": "net/sctp"
}Results: {
"Output": "net/sctp/sm_sideeffect.c=879=static void sctp_cmd_new_state(struct sctp_cmd_seq *cmds,\n--\nnet/sctp/sm_sideeffect.c-922-\t\t/* Wake up any processes waiting in the asoc's wait queue in\nnet/sctp/sm_sideeffect.c:923:\t\t * sctp_wait_for_connect() or sctp_wait_for_sndbuf().\nnet/sctp/sm_sideeffect.c-924-\t\t */\n--\nnet/sctp/socket.c=77=static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);\nnet/sctp/socket.c:78:static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);\nnet/sctp/socket.c-79-static int sctp_wait_for_accept(struct sock *sk, long timeo);\n--\nnet/sctp/socket.c=1167=static int __sctp_connect(struct sock *sk, struct sockaddr *kaddrs,\n--\nnet/sctp/socket.c-1247-\ttimeo = sock_sndtimeo(sk, flags \u0026 O_NONBLOCK);\nnet/sctp/socket.c:1248:\treturn sctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1249-\n--\nnet/sctp/socket.c=1789=static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,\n--\nnet/sctp/socket.c-1845-\t\t\ttimeo = sock_sndtimeo(sk, 0);\nnet/sctp/socket.c:1846:\t\t\terr = sctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1847-\t\t\tif (err || sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN) {\n--\nnet/sctp/socket.c-1883-\t\ttimeo = sock_sndtimeo(sk, msg-\u003emsg_flags \u0026 MSG_DONTWAIT);\nnet/sctp/socket.c:1884:\t\tsctp_wait_for_connect(asoc, \u0026timeo);\nnet/sctp/socket.c-1885-\t}\n--\nnet/sctp/socket.c=9380=static bool sctp_writeable(const struct sock *sk)\n--\nnet/sctp/socket.c-9387- */\nnet/sctp/socket.c:9388:static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)\nnet/sctp/socket.c-9389-{\n"
} |
| 33/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 7209 output: 38 thoughts: 15 Thoughts: Okay, let's dive into this `sctp_wait_for_connect` function. I need to understand what's happening here. **Deconstructing `sctp_wait_for_connect`** Alright, so the first thing I'm doing is looking into the name of this function, `sctp_wait_for_connect`. Based on the naming, I'm expecting this is a function within the SCTP protocol stack that's responsible for managing the connection establishment phase. It's likely blocking, waiting for an association to be established, as the name implies a "wait". My initial assumption is that this will be called after an `sctp_listen` call, where a server application is waiting for a client to initiate an association request, or within a client attempting to establish its own association. I'll need to drill down to understand the different cases. |
| 34/3 | 2026/09/27 23:25 | tool | read-file |
0mArgs:{
"File": "net/sctp/socket.c",
"FirstLine": 9385,
"LineCount": 50
}Results: {
"Contents": "9385:\t/* Wait for an association to go into ESTABLISHED state. If timeout is 0,\n9386:\t * returns immediately with EINPROGRESS.\n9387:\t */\n9388:\tstatic int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)\n9389:\t{\n9390:\t\tstruct sock *sk = asoc-\u003ebase.sk;\n9391:\t\tint err = 0;\n9392:\t\tlong current_timeo = *timeo_p;\n9393:\t\tDEFINE_WAIT(wait);\n9394:\t\n9395:\t\tpr_debug(\"%s: asoc:%p, timeo:%ld\\n\", __func__, asoc, *timeo_p);\n9396:\t\n9397:\t\t/* Increment the association's refcnt. */\n9398:\t\tsctp_association_hold(asoc);\n9399:\t\n9400:\t\tfor (;;) {\n9401:\t\t\tprepare_to_wait_exclusive(\u0026asoc-\u003ewait, \u0026wait,\n9402:\t\t\t\t\t\t TASK_INTERRUPTIBLE);\n9403:\t\t\tif (!*timeo_p)\n9404:\t\t\t\tgoto do_nonblock;\n9405:\t\t\tif (sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN)\n9406:\t\t\t\tbreak;\n9407:\t\t\tif (sk-\u003esk_err || asoc-\u003estate \u003e= SCTP_STATE_SHUTDOWN_PENDING ||\n9408:\t\t\t asoc-\u003ebase.dead)\n9409:\t\t\t\tgoto do_error;\n9410:\t\t\tif (signal_pending(current))\n9411:\t\t\t\tgoto do_interrupted;\n9412:\t\n9413:\t\t\tif (sctp_state(asoc, ESTABLISHED))\n9414:\t\t\t\tbreak;\n9415:\t\n9416:\t\t\t/* Let another process have a go. Since we are going\n9417:\t\t\t * to sleep anyway.\n9418:\t\t\t */\n9419:\t\t\trelease_sock(sk);\n9420:\t\t\tcurrent_timeo = schedule_timeout(current_timeo);\n9421:\t\t\tlock_sock(sk);\n9422:\t\t\tif (sk != asoc-\u003ebase.sk)\n9423:\t\t\t\tgoto do_error;\n9424:\t\n9425:\t\t\t*timeo_p = current_timeo;\n9426:\t\t}\n9427:\t\n9428:\tout:\n9429:\t\tfinish_wait(\u0026asoc-\u003ewait, \u0026wait);\n9430:\t\n9431:\t\t/* Release the association's refcnt. */\n9432:\t\tsctp_association_put(asoc);\n9433:\t\n9434:\t\treturn err;\n"
} |
| 35/3 | 2026/09/27 23:25 | llm | kmsan-evaluator |
0mModel:gemini-3.8-flash Args: null Results: null Tokens: input: 8198 output: 182 thoughts: 1367 Thoughts: **Analysis of SCTP Connection Waiting Logic and KMSAN Justification** Okay, let's break this down. I'm looking at how `sctp_wait_for_connect` and `sctp_sendmsg_to_asoc` interact, specifically in relation to the socket shutdown state. It seems that if `sk->sk_shutdown & RCV_SHUTDOWN` is set, `sctp_wait_for_connect` can return, but it does so *without* setting an error code. Then, the calling function, `sctp_sendmsg_to_asoc`, might proceed as though the connection is valid when, in fact, the socket is shutting down or has already shut down. This could lead to a whole host of nasty issues – null pointer dereferences, state machine errors, even crashes, basically use-after-free scenarios or socket-state bugs. The patch itself is straightforward. It's adding a check: `if (err || sk->sk_shutdown & RCV_SHUTDOWN)` in `sctp_sendmsg_to_asoc`. Now, if the wait returns an error OR the socket is shutting down, it immediately sets `err = -ESRCH` and jumps out. This *prevents* the problematic code path. It's tightening up the error handling, which is good. My immediate focus, however, is on the KMSAN implications. Does this patch *introduce* any uninitialized memory risks? Let's go through the checklist. 1. **Kernel structures to userspace?** No. This just returns an error code. No data is being passed to user space. 2. **Uninitialized variables in conditional logic?** No. The `sk->sk_shutdown` field and `err` are from initialized structures, and the logic is straightforward. 3. **New data structure allocations or initialization with potentially uninitialized fields?** No. There are no new allocations introduced. 4. **Bounds checks, lengths, or logic that could expose uninitialized bytes?** Absolutely not. This *exits* early if there's a problem, thus preventing access. The bugs it prevents are things like use-after-free, null dereference and socket state problems. Those are standard KASAN types of bugs. Therefore, because this patch *removes* potential error conditions and doesn't introduce *any* uninitialized memory usage, KMSAN is not necessary. The kinds of bugs it prevents are well within the scope of KASAN and standard kernel debuggers. There's no uninitialized memory risk here. The patch essentially makes things safer. |
| 36/3 | 2026/09/27 23:25 | tool | set-results |
0mArgs:{
"KMSANReasoning": "The patch adds an error check (`sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN`) in `sctp_sendmsg_to_asoc()` to fail with `-ESRCH` if the socket has received a shutdown while waiting for connection establishment. It does not introduce any new allocations, does not copy kernel memory to user space, and does not alter buffer bounds or data initialization. The fields accessed (`sk-\u003esk_shutdown`) are standard initialized fields of `struct sock`. Any issues previously caused by continuing on a shutdown socket would be socket state errors, NULL pointer dereferences, or use-after-free issues, which are already covered by KASAN and standard kernel debuggers. There is no uninitialized memory risk that requires KMSAN.",
"NeedsKMSAN": false
}Results: {
"KMSANReasoning": "The patch adds an error check (`sk-\u003esk_shutdown \u0026 RCV_SHUTDOWN`) in `sctp_sendmsg_to_asoc()` to fail with `-ESRCH` if the socket has received a shutdown while waiting for connection establishment. It does not introduce any new allocations, does not copy kernel memory to user space, and does not alter buffer bounds or data initialization. The fields accessed (`sk-\u003esk_shutdown`) are standard initialized fields of `struct sock`. Any issues previously caused by continuing on a shutdown socket would be socket state errors, NULL pointer dereferences, or use-after-free issues, which are already covered by KASAN and standard kernel debuggers. There is no uninitialized memory risk that requires KMSAN.",
"NeedsKMSAN": false
} |
| Total Calls | Total Tokens | Avg Tokens | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|
| Total Calls | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|