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=15670d1ce80000
kernel config:
https://syzkaller.appspot.com/x/.config?x=ac34c1f29a8029df
dashboard link:
https://syzkaller.appspot.com/bug?extid=fbbe380cd0f9624f998b
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+fbbe38...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in n_tty_receive_char_flow_ctrl / tty_set_termios
write to 0xffff888149e75d22 of 1 bytes by task 14565 on cpu 0:
unset_locked_termios drivers/tty/tty_ioctl.c:220 [inline]
tty_set_termios+0x4c8/0x8a0 drivers/tty/tty_ioctl.c:340
set_termios+0x47e/0x4c0 drivers/tty/tty_ioctl.c:516
tty_mode_ioctl+0x3e1/0x590
n_tty_ioctl_helper+0x8d/0x240 drivers/tty/tty_ioctl.c:986
n_tty_ioctl+0xfd/0x200 drivers/tty/n_tty.c:2511
tty_ioctl+0x875/0xbc0 drivers/tty/tty_io.c:2789
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 0xffff888149e75d22 of 1 bytes by task 3160 on cpu 1:
n_tty_is_char_flow_ctrl drivers/tty/n_tty.c:1220 [inline]
n_tty_receive_char_flow_ctrl+0x58/0x190 drivers/tty/n_tty.c:1241
n_tty_lookahead_flow_ctrl+0xee/0x130 drivers/tty/n_tty.c:1516
tty_port_default_lookahead_buf+0x87/0xb0 drivers/tty/tty_port.c:59
lookahead_bufs drivers/tty/tty_buffer.c:427 [inline]
flush_to_ldisc+0x30c/0x400 drivers/tty/tty_buffer.c:497
process_one_work kernel/workqueue.c:2630 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
worker_thread+0x525/0x730 kernel/workqueue.c:2784
kthread+0x1d7/0x210 kernel/kthread.c:388
ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
value changed: 0xca -> 0x68
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3160 Comm: kworker/u4:0 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_unbound flush_to_ldisc
==================================================================
---
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