[syzbot] [fs?] KCSAN: data-race in pipe_poll / pipe_release (7)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1fb918967b56 Merge tag 'for-6.11-rc3-tag' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=119e0ad5980000
kernel config: https://syzkaller.appspot.com/x/.config?x=77bd8f74037eecb
dashboard link: https://syzkaller.appspot.com/bug?extid=1f49e6ed8370198296d4
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/63f8e12ef21f/disk-1fb91896.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d776ae2f2dcd/vmlinux-1fb91896.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9636a1ac2746/bzImage-1fb91896.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1f49e6...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in pipe_poll / pipe_release

write to 0xffff888111d4fc68 of 4 bytes by task 12262 on cpu 1:
pipe_release+0xb3/0x1c0 fs/pipe.c:731
__fput+0x192/0x6f0 fs/file_table.c:422
____fput+0x15/0x20 fs/file_table.c:450
task_work_run+0x13a/0x1a0 kernel/task_work.c:228
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x5dd/0x1720 kernel/exit.c:882
do_group_exit+0x142/0x150 kernel/exit.c:1031
__do_sys_exit_group kernel/exit.c:1042 [inline]
__se_sys_exit_group kernel/exit.c:1040 [inline]
__x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1040
x64_sys_call+0x2d5d/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888111d4fc68 of 4 bytes by task 3249 on cpu 0:
pipe_poll+0x17d/0x260 fs/pipe.c:689
vfs_poll include/linux/poll.h:84 [inline]
do_select+0x959/0xfa0 fs/select.c:538
core_sys_select+0x362/0x530 fs/select.c:681
do_pselect fs/select.c:763 [inline]
__do_sys_pselect6 fs/select.c:804 [inline]
__se_sys_pselect6+0x213/0x280 fs/select.c:795
__x64_sys_pselect6+0x78/0x90 fs/select.c:795
x64_sys_call+0x26f7/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:271
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3249 Comm: syz-executor Not tainted 6.11.0-rc3-syzkaller-00066-g1fb918967b56 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.