[moderation] [fs?] KCSAN: data-race in pipe_double_lock / pipe_release (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2e1b3cc9d7f7 Merge tag 'arm-fixes-6.12-2' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14830d87980000
kernel config: https://syzkaller.appspot.com/x/.config?x=8028551073794907
dashboard link: https://syzkaller.appspot.com/bug?extid=df6955318ab0bcec41f9
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/db41c80e5f7f/disk-2e1b3cc9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/64ccdea97c94/vmlinux-2e1b3cc9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c03d235d42cf/bzImage-2e1b3cc9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+df6955...@syzkaller.appspotmail.com

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

read-write to 0xffff888116cf7c6c of 4 bytes by task 15359 on cpu 1:
put_pipe_info fs/pipe.c:712 [inline]
pipe_release+0x15e/0x1c0 fs/pipe.c:742
__fput+0x17a/0x6d0 fs/file_table.c:431
____fput+0x1c/0x30 fs/file_table.c:459
task_work_run+0x13a/0x1a0 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888116cf7c6c of 4 bytes by task 15360 on cpu 0:
pipe_lock fs/pipe.c:91 [inline]
pipe_double_lock+0x5b/0xa0 fs/pipe.c:112
link_pipe fs/splice.c:1891 [inline]
do_tee+0x2e9/0x960 fs/splice.c:1994
__do_sys_tee fs/splice.c:2022 [inline]
__se_sys_tee fs/splice.c:2006 [inline]
__x64_sys_tee+0xc5/0x160 fs/splice.c:2006
x64_sys_call+0x16d3/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:277
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: 0x00000002 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 15360 Comm: syz.6.11624 Tainted: G W 6.12.0-rc6-syzkaller-00077-g2e1b3cc9d7f7 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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[syzbot]

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