[moderation] [fs?] KCSAN: data-race in pipe_lock / pipe_release (15)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3022e9d00ebe Merge tag 'sched_ext-for-6.12-rc7-fixes' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a94ce8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=29fedde79f609854
dashboard link: https://syzkaller.appspot.com/bug?extid=90e7acbb2c8800fe6b7f
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/12ca7a216979/disk-3022e9d0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3afa2bcfd596/vmlinux-3022e9d0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a91dd258e5ba/bzImage-3022e9d0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+90e7ac...@syzkaller.appspotmail.com

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

read-write to 0xffff888105cd22ac of 4 bytes by task 9016 on cpu 0:
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_sync+0x43/0x60 fs/file_table.c:516
__do_sys_close fs/open.c:1567 [inline]
__se_sys_close+0xf9/0x1a0 fs/open.c:1552
__x64_sys_close+0x1f/0x30 fs/open.c:1552
x64_sys_call+0x25cb/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:4
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 0xffff888105cd22ac of 4 bytes by task 9014 on cpu 1:
pipe_lock+0x17/0x50 fs/pipe.c:91
ipipe_prep fs/splice.c:1677 [inline]
splice_pipe_to_pipe fs/splice.c:1752 [inline]
do_splice+0x200/0x1120 fs/splice.c:1331
__do_splice fs/splice.c:1436 [inline]
__do_sys_splice fs/splice.c:1652 [inline]
__se_sys_splice+0x24c/0x390 fs/splice.c:1634
__x64_sys_splice+0x78/0x90 fs/splice.c:1634
x64_sys_call+0x2945/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:276
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: 1 UID: 0 PID: 9014 Comm: syz.5.1564 Not tainted 6.12.0-rc7-syzkaller-00012-g3022e9d00ebe #0
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.