[syzbot] [io-uring?] KCSAN: data-race in __se_sys_io_uring_register / io_sqe_files_register (3)

[syzbot <syzbot+5a486fef3de40e0d8c76@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    2d5404caa8c7 Linux 6.12-rc7
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10e838c0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=29fedde79f609854
dashboard link: https://syzkaller.appspot.com/bug?extid=5a486fef3de40e0d8c76
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/15a7713979b8/disk-2d5404ca.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b51c4f695d4a/vmlinux-2d5404ca.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e8c0f17bc00b/bzImage-2d5404ca.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5a486fef3de40e0d8c76@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __se_sys_io_uring_register / io_sqe_files_register

read-write to 0xffff8881021940b8 of 4 bytes by task 5923 on cpu 1:
 io_sqe_files_register+0x2c4/0x3b0 io_uring/rsrc.c:713
 __io_uring_register io_uring/register.c:403 [inline]
 __do_sys_io_uring_register io_uring/register.c:611 [inline]
 __se_sys_io_uring_register+0x8d0/0x1280 io_uring/register.c:591
 __x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:591
 x64_sys_call+0x202/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:428
 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 0xffff8881021940b8 of 4 bytes by task 5924 on cpu 0:
 __do_sys_io_uring_register io_uring/register.c:613 [inline]
 __se_sys_io_uring_register+0xe4a/0x1280 io_uring/register.c:591
 __x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:591
 x64_sys_call+0x202/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:428
 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: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5924 Comm: syz.1.1000 Not tainted 6.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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