[moderation] [fs?] KCSAN: data-race in pipe_poll / pipe_release (10)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a79be02bba5c Fix mis-uses of 'cc-option' for warning disab..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=149c4574580000
kernel config: https://syzkaller.appspot.com/x/.config?x=85dd0f8b81b9d41f
dashboard link: https://syzkaller.appspot.com/bug?extid=2abb82c72d24b0163531
compiler: Debian clang version 15.0.6, Debian LLD 15.0.6
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/90db06ed4884/disk-a79be02b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9a7e1a6cc767/vmlinux-a79be02b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8d1df5219ca4/bzImage-a79be02b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2abb82...@syzkaller.appspotmail.com

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

write to 0xffff8881185f7668 of 4 bytes by task 27279 on cpu 1:
pipe_release+0xad/0x1c0 fs/pipe.c:732
__fput+0x2ac/0x640 fs/file_table.c:465
____fput+0x1c/0x30 fs/file_table.c:493
task_work_run+0x13c/0x1b0 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x5d8/0x17e0 kernel/exit.c:953
do_group_exit+0x142/0x150 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1111
x64_sys_call+0x2e03/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881185f7668 of 4 bytes by task 3292 on cpu 0:
pipe_poll+0x183/0x270 fs/pipe.c:690
vfs_poll include/linux/poll.h:82 [inline]
select_poll_one fs/select.c:480 [inline]
do_select+0x92b/0xfc0 fs/select.c:536
core_sys_select+0x4c3/0x6d0 fs/select.c:677
do_pselect fs/select.c:759 [inline]
__do_sys_pselect6 fs/select.c:802 [inline]
__se_sys_pselect6+0x212/0x270 fs/select.c:793
__x64_sys_pselect6+0x78/0x90 fs/select.c:793
x64_sys_call+0x1c26/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:271
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3292 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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[syzbot]

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