AI Trajectory

null

{
  "EnableConfigs": [
    "NTFS_FS"
  ],
  "FocusSymbols": [
    "ntfs_write_mft_block"
  ],
  "Reasoning": "The patch fixes a bug in `ntfs_write_mft_block` where a runlist element pointer `rl` could be used uninitialized or as a stale pointer across loop iterations. This is a functional change in the NTFS filesystem driver's MFT writeback path, which is reachable when writing to NTFS volumes. Fuzzing this function will help ensure the correctness of the fix and the MFT writeback logic.",
  "WorthFuzzing": true
}

null

{
  "PatchDiff": "commit cd147284fab7785015d0d56e89627adab4653817\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Thu Jun 25 05:07:32 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/fs/ntfs/mft.c b/fs/ntfs/mft.c\nindex a5019e80951b84..fd20d7abd6f5ec 100644\n--- a/fs/ntfs/mft.c\n+++ b/fs/ntfs/mft.c\n@@ -2637,7 +2637,6 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w\n \ts64 vcn = ntfs_pidx_to_cluster(vol, folio-\u003eindex);\n \ts64 end_vcn = ntfs_bytes_to_cluster(vol, ni-\u003eallocated_size);\n \tunsigned int folio_sz;\n-\tstruct runlist_element *rl = NULL;\n \tloff_t i_size = i_size_read(vi);\n \n \tntfs_debug(\"Entering for inode 0x%llx, attribute type 0x%x, folio index 0x%lx.\",\n@@ -2682,6 +2681,7 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w\n \t\t\t\t\t\u0026tni, \u0026ref_inos[nr_ref_inos])) {\n \t\t\tunsigned int mft_record_off = 0;\n \t\t\ts64 vcn_off = vcn;\n+\t\t\ts64 rl_len = 0;\n \n \t\t\t/*\n \t\t\t * The record should be written.  If a locked ntfs\n@@ -2701,8 +2701,12 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w\n \t\t\t}\n \n \t\t\tif (vol-\u003ecluster_size \u003c folio_size(folio)) {\n+\t\t\t\tstruct runlist_element *rl;\n+\n \t\t\t\tdown_write(\u0026ni-\u003erunlist.lock);\n \t\t\t\trl = ntfs_attr_vcn_to_rl(ni, vcn_off, \u0026lcn);\n+\t\t\t\tif (!IS_ERR(rl))\n+\t\t\t\t\trl_len = rl-\u003elength - (vcn_off - rl-\u003evcn);\n \t\t\t\tup_write(\u0026ni-\u003erunlist.lock);\n \t\t\t\tif (IS_ERR(rl) || lcn \u003c 0) {\n \t\t\t\t\terr = -EIO;\n@@ -2733,7 +2737,7 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w\n \n \t\t\tif (vol-\u003ecluster_size == NTFS_BLOCK_SIZE \u0026\u0026\n \t\t\t    (mft_record_off ||\n-\t\t\t     (rl \u0026\u0026 rl-\u003elength - (vcn_off - rl-\u003evcn) == 1) ||\n+\t\t\t     rl_len == 1 ||\n \t\t\t     mft_ofs + NTFS_BLOCK_SIZE \u003e= PAGE_SIZE))\n \t\t\t\tfolio_sz = NTFS_BLOCK_SIZE;\n \t\t\telse\n"
}

gemini-3.1-pro-preview

null

{
  "EnableConfigs": [
    "NTFS_FS"
  ],
  "FocusSymbols": [
    "ntfs_write_mft_block"
  ],
  "Reasoning": "The patch fixes a bug in `ntfs_write_mft_block` where a runlist element pointer `rl` could be used uninitialized or as a stale pointer across loop iterations. This is a functional change in the NTFS filesystem driver's MFT writeback path, which is reachable when writing to NTFS volumes. Fuzzing this function will help ensure the correctness of the fix and the MFT writeback logic.",
  "WorthFuzzing": true
}

You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Do not list too generic configs (we already have them enabled). Only list those that
   specifically cover the modified code. List them in the EnableConfigs output array,
   and DO NOT add a '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.

For your convenience, here is the diff of the changes:
commit cd147284fab7785015d0d56e89627adab4653817
Author: syz-cluster <triage@syzkaller.com>
Date:   Thu Jun 25 05:07:32 2026 +0000

    syz-cluster: applied patch under review

diff --git a/fs/ntfs/mft.c b/fs/ntfs/mft.c
index a5019e80951b84..fd20d7abd6f5ec 100644
--- a/fs/ntfs/mft.c
+++ b/fs/ntfs/mft.c
@@ -2637,7 +2637,6 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w
 	s64 vcn = ntfs_pidx_to_cluster(vol, folio->index);
 	s64 end_vcn = ntfs_bytes_to_cluster(vol, ni->allocated_size);
 	unsigned int folio_sz;
-	struct runlist_element *rl = NULL;
 	loff_t i_size = i_size_read(vi);
 
 	ntfs_debug("Entering for inode 0x%llx, attribute type 0x%x, folio index 0x%lx.",
@@ -2682,6 +2681,7 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w
 					&tni, &ref_inos[nr_ref_inos])) {
 			unsigned int mft_record_off = 0;
 			s64 vcn_off = vcn;
+			s64 rl_len = 0;
 
 			/*
 			 * The record should be written.  If a locked ntfs
@@ -2701,8 +2701,12 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w
 			}
 
 			if (vol->cluster_size < folio_size(folio)) {
+				struct runlist_element *rl;
+
 				down_write(&ni->runlist.lock);
 				rl = ntfs_attr_vcn_to_rl(ni, vcn_off, &lcn);
+				if (!IS_ERR(rl))
+					rl_len = rl->length - (vcn_off - rl->vcn);
 				up_write(&ni->runlist.lock);
 				if (IS_ERR(rl) || lcn < 0) {
 					err = -EIO;
@@ -2733,7 +2737,7 @@ static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *w
 
 			if (vol->cluster_size == NTFS_BLOCK_SIZE &&
 			    (mft_record_off ||
-			     (rl && rl->length - (vcn_off - rl->vcn) == 1) ||
+			     rl_len == 1 ||
 			     mft_ofs + NTFS_BLOCK_SIZE >= PAGE_SIZE))
 				folio_sz = NTFS_BLOCK_SIZE;
 			else

gemini-3.1-pro-preview

null

null

							input: 2338
							output: 23
							thoughts: 372
						

**Analyzing the NTFS MFT Block Write Patch**

Okay, so I'm looking at this patch in `fs/ntfs/mft.c` that tweaks the `ntfs_write_mft_block` function. The key changes are all about how they're handling this `rl` variable, the runlist element.

Initially, `struct runlist_element *rl = NULL;` was declared outside the loop. The patch removes this declaration from the outer scope and adds `s64 rl_len = 0;` inside the loop.  That's already a good sign, scoping variables closer to where they're used is generally cleaner. It also moves the actual `struct runlist_element *rl;` declaration into this `if (vol->cluster_size < folio_size(folio))` block.

The crucial part is the conditional logic.  Before, they had `(rl && rl->length - (vcn_off - rl->vcn) == 1)`.  The patch changes this to `rl_len == 1`.  It looks like they're now calculating `rl_len = rl->length - (vcn_off - rl->vcn)` within the block with `rl` only when `!IS_ERR(rl)`.

Alright, I see the problem now. Before, `rl` was declared outside that block. If `vol->cluster_size < folio_size(folio)` was *false* in a given iteration, `rl` wouldn't be re-assigned.  So, in subsequent iterations, `rl` would retain its value from the previous loop iteration. If it was `NULL` in the first iteration, then the conditional logic would be safe, but if it was set in a previous iteration, it's a stale pointer! This means there's a serious potential for use-after-free, out-of-bounds reads, or just completely wrong logic being executed because we're dereferencing a pointer that could be garbage. This is definitely a functional bug!

I need to confirm this by going back and verifying. Let's see...I'll quickly use `grepper` to locate `ntfs_write_mft_block` in `fs/ntfs/mft.c` and make sure my understanding is correct and that the patch resolves the issue.

{
  "Expression": "ntfs_write_mft_block"
}

{
  "Output": "fs/ntfs/mft.c=2593=static s64 lcn_from_index(struct ntfs_volume *vol, struct ntfs_inode *ni,\n--\nfs/ntfs/mft.c-2608-/*\nfs/ntfs/mft.c:2609: * ntfs_write_mft_block - Write back a folio containing MFT records\nfs/ntfs/mft.c-2610- * @folio:\tThe folio to write back (contains one or more MFT records)\n--\nfs/ntfs/mft.c-2619- */\nfs/ntfs/mft.c:2620:static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *wbc)\nfs/ntfs/mft.c-2621-{\n--\nfs/ntfs/mft.c-2821- * Writeback iterator for MFT records. Iterates over dirty folios and\nfs/ntfs/mft.c:2822: * delegates actual writing to ntfs_write_mft_block() for each folio.\nfs/ntfs/mft.c-2823- * Called from the address_space_operations .writepages vector of the\n--\nfs/ntfs/mft.c=2828=int ntfs_mft_writepages(struct address_space *mapping,\n--\nfs/ntfs/mft.c-2837-\twhile ((folio = writeback_iter(mapping, wbc, folio, \u0026error)))\nfs/ntfs/mft.c:2838:\t\terror = ntfs_write_mft_block(folio, wbc);\nfs/ntfs/mft.c-2839-\treturn error;\n"
}

gemini-3.1-pro-preview

null

null

							input: 3679
							output: 18
							thoughts: 47
						

Here's my summary, as though I'm thinking through this process:

**Diving into the NTFS Write Operation**

Okay, so I'm looking at `ntfs_write_mft_block`, which is triggered by `ntfs_mft_writepages`. Right, this is all part of the NTFS filesystem driver, which I'm very familiar with. Let's make sure our configuration is set up properly before delving deeper. I need to quickly cross-reference the Kconfig to confirm the relevant NTFS features are enabled. This call chain implies a critical write operation – probably involving the Metadata File Table (MFT) itself, so it's good to ensure all related components are active.

{
  "Expression": "config NTFS_FS"
}

{
  "Output": "fs/ntfs/Kconfig-1-# SPDX-License-Identifier: GPL-2.0-only\nfs/ntfs/Kconfig:2:config NTFS_FS\nfs/ntfs/Kconfig-3-\ttristate \"NTFS file system support\"\n--\nfs/ntfs/Kconfig=13=config NTFS_DEBUG\n--\nfs/ntfs/Kconfig-34-\nfs/ntfs/Kconfig:35:config NTFS_FS_POSIX_ACL\nfs/ntfs/Kconfig-36-\tbool \"NTFS POSIX Access Control Lists\"\n"
}

gemini-3.1-pro-preview

null

null

							input: 4041
							output: 18
							thoughts: 85
						

Okay, let's see what we have here.

**Analyzing the NTFS Filesystem Configuration**

Right, so the system is configured to use `NTFS_FS`. But hang on, I see another NTFS driver lurking in `fs/ntfs3/`, named `NTFS3_FS`. The patch I'm examining is located in `fs/ntfs/mft.c`, which makes it clear that we're dealing with the *original* NTFS driver, not the newer NTFS3. The config still confirms `NTFS_FS`.

Now, I need to make sure I'm not missing anything. I'll quickly glance at the other related configurations to see if something like `NTFS_RW` is set or unset. That could influence the current situation. I'll need to figure out what the implications of the other config choices are.

no matches

{
  "Expression": "config NTFS_RW"
}

{
  "error": "no matches"
}

gemini-3.1-pro-preview

null

null

							input: 4340
							output: 34
							thoughts: 23
						

Here's my thought process, summarized as you requested:

**Investigating NTFS Write Support Configuration**

Alright, let's dive into this. Given the context, my initial instinct is to pinpoint the configuration option controlling NTFS write support. To do that, I'll navigate directly to the heart of the file system configuration: `fs/ntfs/Kconfig`. This is where all the relevant Kconfig options pertaining to the NTFS file system should reside. This file will undoubtedly hold the key to understanding if write support is enabled, disabled, or conditionally configured. I expect to find a boolean option, or perhaps even a tristate, directly related to NTFS write functionality. From there, I can determine the current setting and any dependencies involved. That's my starting point, let's go check it.

{
  "File": "fs/ntfs/Kconfig",
  "FirstLine": 1,
  "LineCount": 100
}

{
  "Contents": "   1:\t# SPDX-License-Identifier: GPL-2.0-only\n   2:\tconfig NTFS_FS\n   3:\t\ttristate \"NTFS file system support\"\n   4:\t\tselect NLS\n   5:\t\tselect FS_IOMAP\n   6:\t\thelp\n   7:\t\t  NTFS is the file system of Microsoft Windows NT, 2000, XP and 2003.\n   8:\t\t  This allows you to mount devices formatted with the ntfs file system.\n   9:\t\n  10:\t\t  To compile this as a module, choose M here: the module will be called\n  11:\t\t  ntfs.\n  12:\t\n  13:\tconfig NTFS_DEBUG\n  14:\t\tbool \"NTFS debugging support\"\n  15:\t\tdepends on NTFS_FS\n  16:\t\thelp\n  17:\t\t  If you are experiencing any problems with the NTFS file system, say\n  18:\t\t  Y here.  This will result in additional consistency checks to be\n  19:\t\t  performed by the driver as well as additional debugging messages to\n  20:\t\t  be written to the system log.  Note that debugging messages are\n  21:\t\t  disabled by default.  To enable them, supply the option debug_msgs=1\n  22:\t\t  at the kernel command line when booting the kernel or as an option\n  23:\t\t  to insmod when loading the ntfs module.  Once the driver is active,\n  24:\t\t  you can enable debugging messages by doing (as root):\n  25:\t\t  echo 1 \u003e /proc/sys/fs/ntfs-debug\n  26:\t\t  Replacing the \"1\" with \"0\" would disable debug messages.\n  27:\t\n  28:\t\t  If you leave debugging messages disabled, this results in little\n  29:\t\t  overhead, but enabling debug messages results in very significant\n  30:\t\t  slowdown of the system.\n  31:\t\n  32:\t\t  When reporting bugs, please try to have available a full dump of\n  33:\t\t  debugging messages while the misbehaviour was occurring.\n  34:\t\n  35:\tconfig NTFS_FS_POSIX_ACL\n  36:\t\tbool \"NTFS POSIX Access Control Lists\"\n  37:\t\tdepends on NTFS_FS\n  38:\t\tselect FS_POSIX_ACL\n  39:\t\thelp\n  40:\t\t  POSIX Access Control Lists (ACLs) support additional access rights\n  41:\t\t  for users and groups beyond the standard owner/group/world scheme.\n  42:\t\n  43:\t\t  This option enables ACL support for ntfs, providing functional parity\n  44:\t\t  with ntfs3 drivier.\n  45:\t\n  46:\t\t  NOTE: this is linux only feature. Windows will ignore these ACLs.\n  47:\t\n  48:\t\t  If you don't know what Access Control Lists are, say N.\n"
}

gemini-3.1-pro-preview

null

null

							input: 5284
							output: 33
							thoughts: 23
						

Here's my attempt at summarizing the thought process, tailored for an expert audience:

**Damn, Did `NTFS_RW` Really Go Away?**

Hold on a second... `NTFS_RW` got axed? That's a bit of a surprise. Right, time to verify. The first place I'd check is the source. Specifically, the build configuration file for the NTFS filesystem component, which should be the `fs/ntfs/Makefile`. Time to crack that open and see what's actually going on in there and see how that variable, or its replacement, is being handled.

{
  "File": "fs/ntfs/Makefile",
  "FirstLine": 1,
  "LineCount": 100
}

{
  "Contents": "   1:\t# SPDX-License-Identifier: GPL-2.0\n   2:\t\n   3:\tobj-$(CONFIG_NTFS_FS) += ntfs.o\n   4:\t\n   5:\tntfs-y := aops.o attrib.o collate.o dir.o file.o index.o inode.o \\\n   6:\t\t  mft.o mst.o namei.o runlist.o super.o unistr.o attrlist.o ea.o \\\n   7:\t\t  upcase.o bitmap.o lcnalloc.o logfile.o reparse.o compress.o \\\n   8:\t\t  iomap.o debug.o sysctl.o object_id.o bdev-io.o\n   9:\t\n  10:\tccflags-$(CONFIG_NTFS_DEBUG) += -DDEBUG\n"
}

gemini-3.1-pro-preview

null

null

							input: 5685
							output: 23
							thoughts: 75
						

Okay, let me think this through.

**NTFS Write Support: A Quick Investigation**

Alright, so `NTFS_RW` is gone – that's the first thing that jumps out at me. The question is, has write support been integrated directly into the core, or are we now dealing with a read-only scenario? My gut says there was some recent shuffling around with the NTFS code, perhaps a patch series that shifted things, but I'm not entirely sure where it landed. Was `NTFS_RW` removed because write capabilities were removed or were they actually always available?

The best way to figure this out definitively is to go straight to the source. I'll need to check `fs/ntfs/super.c`. That's where the filesystem's superblock and its related functionality are defined, which should give me the clearest indication of how write support is currently handled, if at all. I need to see how the code is structured around write-related operations. That's where the truth lies.

{
  "Expression": "ntfs_write_mft_block"
}

{
  "Output": "fs/ntfs/mft.c=2593=static s64 lcn_from_index(struct ntfs_volume *vol, struct ntfs_inode *ni,\n--\nfs/ntfs/mft.c-2608-/*\nfs/ntfs/mft.c:2609: * ntfs_write_mft_block - Write back a folio containing MFT records\nfs/ntfs/mft.c-2610- * @folio:\tThe folio to write back (contains one or more MFT records)\n--\nfs/ntfs/mft.c-2619- */\nfs/ntfs/mft.c:2620:static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *wbc)\nfs/ntfs/mft.c-2621-{\n--\nfs/ntfs/mft.c-2821- * Writeback iterator for MFT records. Iterates over dirty folios and\nfs/ntfs/mft.c:2822: * delegates actual writing to ntfs_write_mft_block() for each folio.\nfs/ntfs/mft.c-2823- * Called from the address_space_operations .writepages vector of the\n--\nfs/ntfs/mft.c=2828=int ntfs_mft_writepages(struct address_space *mapping,\n--\nfs/ntfs/mft.c-2837-\twhile ((folio = writeback_iter(mapping, wbc, folio, \u0026error)))\nfs/ntfs/mft.c:2838:\t\terror = ntfs_write_mft_block(folio, wbc);\nfs/ntfs/mft.c-2839-\treturn error;\n"
}

gemini-3.1-pro-preview

null

null

							input: 6446
							output: 22
							thoughts: 104
						

**Analyzing the NTFS MFT Block Write Function**

Okay, so I'm diving into this `ntfs_write_mft_block` function. I see it's defined in `fs/ntfs/mft.c`. My initial thought is to figure out if there are any specific configuration parameters or flags I need to consider for this function's behavior. Based on the file location, I'm guessing the general NTFS filesystem support (`NTFS_FS`) is the relevant compile time configuration flag. But I should confirm this.

Now, a key question is, where is this function actually *used*? I need to understand its call hierarchy. Let me check... Ah, it's called from `ntfs_mft_writepages`. Okay, that's helpful. Now, where is *that* called? My hunch is this relates to the page writeback machinery. So, likely `fs/ntfs/aops.c`. I'll confirm that connection, of course. Need to see how this fits into the larger picture of NTFS's file system operation.

{
  "Expression": "ntfs_mft_writepages"
}

{
  "Output": "fs/ntfs/aops.c=294=const struct address_space_operations ntfs_mft_aops = {\n--\nfs/ntfs/aops.c-296-\t.readahead\t\t= ntfs_readahead,\nfs/ntfs/aops.c:297:\t.writepages\t\t= ntfs_mft_writepages,\nfs/ntfs/aops.c-298-\t.dirty_folio\t\t= iomap_dirty_folio,\n--\nfs/ntfs/mft.c=2620=static int ntfs_write_mft_block(struct folio *folio, struct writeback_control *wbc)\n--\nfs/ntfs/mft.c-2816-/*\nfs/ntfs/mft.c:2817: * ntfs_mft_writepages - Write back dirty folios for the $MFT inode\nfs/ntfs/mft.c-2818- * @mapping:\taddress space of the $MFT inode\n--\nfs/ntfs/mft.c-2827- */\nfs/ntfs/mft.c:2828:int ntfs_mft_writepages(struct address_space *mapping,\nfs/ntfs/mft.c-2829-\t\tstruct writeback_control *wbc)\n--\nfs/ntfs/mft.h=85=int ntfs_mft_record_check(const struct ntfs_volume *vol, struct mft_record *m,\nfs/ntfs/mft.h-86-\t\t\t  u64 mft_no);\nfs/ntfs/mft.h:87:int ntfs_mft_writepages(struct address_space *mapping,\nfs/ntfs/mft.h-88-\t\tstruct writeback_control *wbc);\n"
}

gemini-3.1-pro-preview

null

null

							input: 7265
							output: 136
							thoughts: 982
						

**Analysis of NTFS MFT Writeback Function**

Okay, so I've been tracing the `ntfs_mft_writepages` function, and as expected, it's definitely part of the `ntfs_mft_aops` structure, which handles address space operations for the MFT inode. That means, whenever the MFT inode is written back to disk, it will call `ntfs_mft_writepages`, which in turn calls `ntfs_write_mft_block`.  So far, so good – we've got a clear path through the relevant functions.

Now, the config used here is `NTFS_FS`, no other configs are relevant. The key functions to focus on for this fix are `ntfs_write_mft_block` and `ntfs_mft_writepages`.

Looking through the changes, it seems that only `ntfs_write_mft_block` has been modified. This seems like a potential bug fix, specifically addressing a use-after-free or uninitialized variable issue.

I've examined the diff, and I'm quite confident in the path and focus. I'll set `WorthFuzzing` to `true` as it seems a solid area for fuzzing.
For my fuzzing effort, my `FocusSymbols` will be `ntfs_write_mft_block`. I will also only enable the `NTFS_FS` config, that seems sufficient for reproducing this.

Just to be absolutely certain, I'll quickly double-check the `fs/ntfs/Kconfig` file again. `NTFS_FS` is the main one and, yes, there are other configs such as `NTFS_DEBUG` and `NTFS_FS_POSIX_ACL`, but none of them are required for this particular code path.  So, I can confirm that `NTFS_FS` is the only config I need.

Alright, I'm ready to `set-results`.

{
  "EnableConfigs": [
    "NTFS_FS"
  ],
  "FocusSymbols": [
    "ntfs_write_mft_block"
  ],
  "Reasoning": "The patch fixes a bug in `ntfs_write_mft_block` where a runlist element pointer `rl` could be used uninitialized or as a stale pointer across loop iterations. This is a functional change in the NTFS filesystem driver's MFT writeback path, which is reachable when writing to NTFS volumes. Fuzzing this function will help ensure the correctness of the fix and the MFT writeback logic.",
  "WorthFuzzing": true
}

{
  "EnableConfigs": [
    "NTFS_FS"
  ],
  "FocusSymbols": [
    "ntfs_write_mft_block"
  ],
  "Reasoning": "The patch fixes a bug in `ntfs_write_mft_block` where a runlist element pointer `rl` could be used uninitialized or as a stale pointer across loop iterations. This is a functional change in the NTFS filesystem driver's MFT writeback path, which is reachable when writing to NTFS volumes. Fuzzing this function will help ensure the correctness of the fix and the MFT writeback logic.",
  "WorthFuzzing": true
}