[moderation] [serial?] KCSAN: data-race in __se_sys_ioctl / __tty_hangup (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: bee0e7762ad2 Merge tag 'for-linus-iommufd' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14c9a986e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=ac34c1f29a8029df
dashboard link: https://syzkaller.appspot.com/bug?extid=78cbd9047e9c2f144fbc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [gre...@linuxfoundation.org jiri...@kernel.org 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/233be5f65dd2/disk-bee0e776.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/94423738a289/vmlinux-bee0e776.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0b977463fa9a/bzImage-bee0e776.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+78cbd9...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __se_sys_ioctl / __tty_hangup

write to 0xffff8881099686b0 of 8 bytes by task 18867 on cpu 1:
__tty_hangup+0x1e8/0x530 drivers/tty/tty_io.c:621
tty_vhangup drivers/tty/tty_io.c:700 [inline]
tty_ioctl+0x60a/0xbc0 drivers/tty/tty_io.c:2720
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
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 0xffff8881099686b0 of 8 bytes by task 18869 on cpu 0:
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xa6/0x140 fs/ioctl.c:857
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
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: 0xffffffff84e96298 -> 0xffffffff84e96130

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18869 Comm: syz-executor.4 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #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.