[moderation] [fs?] KCSAN: data-race in aio_read_events / iocb_put (13)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 24d479d26b25 Linux 6.19-rc6
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=112d33fa580000
kernel config: https://syzkaller.appspot.com/x/.config?x=676c6f0212d0c041
dashboard link: https://syzkaller.appspot.com/bug?extid=afa258ce86594613760c
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
CC: [bc...@kvack.org bra...@kernel.org ja...@suse.cz linu...@kvack.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/e47d2b960e97/disk-24d479d2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/75c59e1fc76a/vmlinux-24d479d2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e42579adf478/bzImage-24d479d2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+afa258...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in aio_read_events / iocb_put

write to 0xffff8881056e6008 of 4 bytes by task 12674 on cpu 0:
aio_read_events_ring fs/aio.c:1285 [inline]
aio_read_events+0x2f7/0x400 fs/aio.c:1298
read_events fs/aio.c:1334 [inline]
do_io_getevents+0x11b/0x450 fs/aio.c:2230
__do_sys_io_getevents fs/aio.c:2263 [inline]
__se_sys_io_getevents fs/aio.c:2251 [inline]
__x64_sys_io_getevents+0xca/0x190 fs/aio.c:2251
x64_sys_call+0x1893/0x3000 arch/x86/include/generated/asm/syscalls_64.h:209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881056e6008 of 4 bytes by task 12671 on cpu 1:
aio_complete fs/aio.c:1161 [inline]
iocb_put+0x17a/0x680 fs/aio.c:1209
io_submit_one+0xbcb/0x1350 fs/aio.c:2056
__do_sys_io_submit fs/aio.c:2112 [inline]
__se_sys_io_submit+0xfb/0x280 fs/aio.c:2082
__x64_sys_io_submit+0x43/0x50 fs/aio.c:2082
x64_sys_call+0x2e40/0x3000 arch/x86/include/generated/asm/syscalls_64.h:210
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000014 -> 0x0000001b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 12671 Comm: syz.7.7949 Tainted: G W syzkaller #0 PREEMPT(voluntary)
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================


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