[moderation] [fs?] KCSAN: data-race in fifo_open / wait_for_partner (5)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 18737353cca0 Merge tag 'edac_urgent_for_v6.9_rc2' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1027cdc3180000
kernel config: https://syzkaller.appspot.com/x/.config?x=aa27611f143168c9
dashboard link: https://syzkaller.appspot.com/bug?extid=6f8fb953e2a2f8a0a8ff
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/736d9b554211/disk-18737353.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/33808fe02e70/vmlinux-18737353.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1b59be54e42c/bzImage-18737353.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6f8fb9...@syzkaller.appspotmail.com

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

read-write to 0xffff88811122c96c of 4 bytes by task 17514 on cpu 1:
fifo_open+0xa0/0x5e0 fs/pipe.c:1116
do_dentry_open+0x63c/0xbe0 fs/open.c:955
vfs_open+0x4a/0x60 fs/open.c:1089
do_open fs/namei.c:3642 [inline]
path_openat+0x18ba/0x1d80 fs/namei.c:3799
do_filp_open+0xf7/0x200 fs/namei.c:3826
file_open_name+0xf6/0x120 fs/open.c:1351
acct_on kernel/acct.c:226 [inline]
__do_sys_acct kernel/acct.c:305 [inline]
__se_sys_acct+0xec/0x420 kernel/acct.c:292
__x64_sys_acct+0x1f/0x30 kernel/acct.c:292
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

read to 0xffff88811122c96c of 4 bytes by task 17521 on cpu 0:
pipe_unlock fs/pipe.c:98 [inline]
wait_for_partner+0xc7/0x1e0 fs/pipe.c:1090
fifo_open+0x483/0x5e0 fs/pipe.c:1160
do_dentry_open+0x63c/0xbe0 fs/open.c:955
vfs_open+0x4a/0x60 fs/open.c:1089
do_open fs/namei.c:3642 [inline]
path_openat+0x18ba/0x1d80 fs/namei.c:3799
do_filp_open+0xf7/0x200 fs/namei.c:3826
do_sys_openat2+0xab/0x120 fs/open.c:1406
do_sys_open fs/open.c:1421 [inline]
__do_sys_open fs/open.c:1429 [inline]
__se_sys_open fs/open.c:1425 [inline]
__x64_sys_open+0xe6/0x110 fs/open.c:1425
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

value changed: 0x00000001 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17521 Comm: syz-executor.1 Tainted: G W 6.9.0-rc1-syzkaller-00379-g18737353cca0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================


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