linux-kernel - [syzbot] [fs?] KMSAN: uninit-value in fsnotify_connector_destroy

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Message-ID: <6853c84d.050a0220.216029.01ca.GAE@google.com>
Date: Thu, 19 Jun 2025 01:20:29 -0700
From: syzbot <syzbot+aaeb1646d01d0358cb2a@...kaller.appspotmail.com>
To: amir73il@...il.com, jack@...e.cz, linux-fsdevel@...r.kernel.org, 
	linux-kernel@...r.kernel.org, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [fs?] KMSAN: uninit-value in fsnotify_connector_destroy_workfn

Hello,

syzbot found the following issue on:

HEAD commit:    8c6bc74c7f89 Merge tag 'v6.16-rc1-smb3-client-fixes' of gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14c9bd70580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=61539536677af51c
dashboard link: https://syzkaller.appspot.com/bug?extid=aaeb1646d01d0358cb2a
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fa187645a1d3/disk-8c6bc74c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9c5f24a0cd2d/vmlinux-8c6bc74c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c2cd7c92032f/bzImage-8c6bc74c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+aaeb1646d01d0358cb2a@...kaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in fsnotify_connector_destroy_workfn+0x108/0x160 fs/notify/mark.c:323
 fsnotify_connector_destroy_workfn+0x108/0x160 fs/notify/mark.c:323
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xb91/0x1d80 kernel/workqueue.c:3321
 worker_thread+0xedf/0x1590 kernel/workqueue.c:3402
 kthread+0xd5c/0xf00 kernel/kthread.c:464
 ret_from_fork+0x1e0/0x310 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x81b/0xec0 mm/slub.c:4204
 fsnotify_attach_connector_to_object fs/notify/mark.c:663 [inline]
 fsnotify_add_mark_list fs/notify/mark.c:746 [inline]
 fsnotify_add_mark_locked+0x862/0x1a90 fs/notify/mark.c:821
 fsnotify_add_inode_mark_locked include/linux/fsnotify_backend.h:888 [inline]
 inotify_new_watch fs/notify/inotify/inotify_user.c:620 [inline]
 inotify_update_watch fs/notify/inotify/inotify_user.c:647 [inline]
 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:781 [inline]
 __se_sys_inotify_add_watch+0x129c/0x1760 fs/notify/inotify/inotify_user.c:729
 __x64_sys_inotify_add_watch+0x97/0xe0 fs/notify/inotify/inotify_user.c:729
 x64_sys_call+0x330f/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 4808 Comm: kworker/u8:25 Tainted: G      D W           6.16.0-rc1-syzkaller-00236-g8c6bc74c7f89 #0 PREEMPT(undef) 
Tainted: [D]=DIE, [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound fsnotify_connector_destroy_workfn

=====================================================


---
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