[moderation] [fs?] KCSAN: data-race in fifo_open / wait_for_partner (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b47bc037bd4 Merge tag 'pinctrl-v6.7-2' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16dd9eb4e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=585869067cd7ce59
dashboard link: https://syzkaller.appspot.com/bug?extid=b7d953e0f3c3d6973332
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org 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/231e21487056/disk-3b47bc03.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/eae871bb6b73/vmlinux-3b47bc03.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0c20f8f08d47/bzImage-3b47bc03.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b7d953...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in fifo_open / wait_for_partner

read-write to 0xffff888152e9d7ec of 4 bytes by task 19661 on cpu 0:
fifo_open+0xa0/0x5e0 fs/pipe.c:1118
do_dentry_open+0x635/0xbd0 fs/open.c:948
vfs_open+0x4a/0x50 fs/open.c:1082
do_open fs/namei.c:3622 [inline]
path_openat+0x1819/0x1d70 fs/namei.c:3779
do_filp_open+0xf6/0x200 fs/namei.c:3809
do_sys_openat2+0xab/0x110 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1466
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888152e9d7ec of 4 bytes by task 19670 on cpu 1:
pipe_unlock fs/pipe.c:96 [inline]
wait_for_partner+0xc6/0x1d0 fs/pipe.c:1092
fifo_open+0x483/0x5e0 fs/pipe.c:1162
do_dentry_open+0x635/0xbd0 fs/open.c:948
vfs_open+0x4a/0x50 fs/open.c:1082
do_open fs/namei.c:3622 [inline]
path_openat+0x1819/0x1d70 fs/namei.c:3779
do_filp_open+0xf6/0x200 fs/namei.c:3809
do_sys_openat2+0xab/0x110 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1466
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000001 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19670 Comm: syz-executor.3 Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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[syzbot]

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