[moderation] [input?] KCSAN: data-race in evdev_pass_values / evdev_poll (7)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 994d5c58e50e Merge tag 'hardening-v6.7-rc4' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=159022f8e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=efc18f367a3f97fa
dashboard link: https://syzkaller.appspot.com/bug?extid=369d2969218bc52f57db
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [dmitry....@gmail.com linux...@vger.kernel.org linux-...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/77b2fa385c10/disk-994d5c58.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a10e02299372/vmlinux-994d5c58.xz
kernel image: https://storage.googleapis.com/syzbot-assets/73ebc6f961cc/bzImage-994d5c58.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+369d29...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in evdev_pass_values / evdev_poll

write to 0xffff888102bb9808 of 4 bytes by task 11376 on cpu 1:
__pass_event drivers/input/evdev.c:239 [inline]
evdev_pass_values+0x3a8/0x510 drivers/input/evdev.c:278
evdev_events+0x90/0xd0 drivers/input/evdev.c:306
input_to_handler drivers/input/input.c:129 [inline]
input_pass_values+0x305/0x770 drivers/input/input.c:161
input_event_dispose+0x243/0x310 drivers/input/input.c:378
input_handle_event+0xac0/0xaf0 drivers/input/input.c:406
input_inject_event+0xd1/0xf0 drivers/input/input.c:465
evdev_write+0x332/0x410 drivers/input/evdev.c:530
vfs_write+0x27a/0x790 fs/read_write.c:582
ksys_write+0xeb/0x1a0 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:646
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 0xffff888102bb9808 of 4 bytes by task 2763 on cpu 0:
evdev_poll+0xe1/0x110 drivers/input/evdev.c:623
vfs_poll include/linux/poll.h:88 [inline]
do_select+0x954/0xf90 fs/select.c:538
core_sys_select+0x361/0x520 fs/select.c:681
do_pselect fs/select.c:763 [inline]
__do_sys_pselect6 fs/select.c:804 [inline]
__se_sys_pselect6+0x213/0x280 fs/select.c:795
__x64_sys_pselect6+0x78/0x90 fs/select.c:795
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: 0x0000001e -> 0x00000020

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2763 Comm: acpid Tainted: G W 6.7.0-rc3-syzkaller-00134-g994d5c58e50e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

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