[moderation] [fs?] KCSAN: data-race in pipe_poll / pipe_release (9)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 05dbaf8dd8bf Merge tag 'x86-urgent-2025-01-28' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11a9a924580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8ebd5d2ccdb8d898
dashboard link: https://syzkaller.appspot.com/bug?extid=5ca9e5560e119c051578
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
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/ea44ceba50b1/disk-05dbaf8d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5a339cb6a7e6/vmlinux-05dbaf8d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dc054132a354/bzImage-05dbaf8d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5ca9e5...@syzkaller.appspotmail.com

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

write to 0xffff88814d5cc8a8 of 4 bytes by task 8457 on cpu 0:
pipe_release+0xad/0x1c0 fs/pipe.c:732
__fput+0x2ac/0x640 fs/file_table.c:450
____fput+0x1c/0x30 fs/file_table.c:478
task_work_run+0x13a/0x1a0 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x5d8/0x17f0 kernel/exit.c:938
do_group_exit+0x142/0x150 kernel/exit.c:1087
__do_sys_exit_group kernel/exit.c:1098 [inline]
__se_sys_exit_group kernel/exit.c:1096 [inline]
__x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1096
x64_sys_call+0x2db8/0x2dc0 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 0xffff88814d5cc8a8 of 4 bytes by task 3283 on cpu 1:
pipe_poll+0x173/0x250 fs/pipe.c:690
vfs_poll include/linux/poll.h:82 [inline]
select_poll_one fs/select.c:480 [inline]
do_select+0x8d4/0xfc0 fs/select.c:536
core_sys_select+0x362/0x530 fs/select.c:677
do_pselect fs/select.c:759 [inline]
__do_sys_pselect6 fs/select.c:802 [inline]
__se_sys_pselect6+0x21b/0x280 fs/select.c:793
__x64_sys_pselect6+0x78/0x90 fs/select.c:793
x64_sys_call+0x2ac2/0x2dc0 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: 1 UID: 0 PID: 3283 Comm: syz-executor Not tainted 6.13.0-syzkaller-09338-g05dbaf8dd8bf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================


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[syzbot]

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