Hello,
syzbot found the following crash on:
HEAD commit: ef798c30 x86, kcsan: Enable KCSAN for x86
git tree:
https://github.com/google/ktsan.git kcsan
console output:
https://syzkaller.appspot.com/x/log.txt?x=15027646e00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=8077a73bd604a9d4
dashboard link:
https://syzkaller.appspot.com/bug?extid=6636788b7ec318c30f07
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [
gre...@linuxfoundation.org jsl...@suse.com
linux-...@vger.kernel.org el...@google.com]
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+663678...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in n_tty_receive_buf_common /
n_tty_receive_char_special
write to 0xffffc90000de9000 of 8 bytes by task 28 on cpu 0:
put_tty_queue drivers/tty/n_tty.c:320 [inline]
n_tty_receive_char_fast drivers/tty/n_tty.c:1451 [inline]
n_tty_receive_buf_fast drivers/tty/n_tty.c:1609 [inline]
__receive_buf drivers/tty/n_tty.c:1644 [inline]
n_tty_receive_buf_common+0x177a/0x1b00 drivers/tty/n_tty.c:1742
n_tty_receive_buf2+0x3d/0x60 drivers/tty/n_tty.c:1777
tty_ldisc_receive_buf+0x71/0xf0 drivers/tty/tty_buffer.c:461
tty_port_default_receive_buf+0x87/0xd0 drivers/tty/tty_port.c:38
receive_buf drivers/tty/tty_buffer.c:481 [inline]
flush_to_ldisc+0x1d5/0x260 drivers/tty/tty_buffer.c:533
process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
worker_thread+0xa0/0x800 kernel/workqueue.c:2415
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
read to 0xffffc90000de9000 of 8 bytes by task 8882 on cpu 1:
n_tty_receive_char_special+0xb67/0x1c10 drivers/tty/n_tty.c:1338
n_tty_receive_buf_fast drivers/tty/n_tty.c:1610 [inline]
__receive_buf drivers/tty/n_tty.c:1644 [inline]
n_tty_receive_buf_common+0x1844/0x1b00 drivers/tty/n_tty.c:1742
n_tty_receive_buf+0x3a/0x50 drivers/tty/n_tty.c:1771
tiocsti drivers/tty/tty_io.c:2197 [inline]
tty_ioctl+0xb75/0xe10 drivers/tty/tty_io.c:2573
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696
ksys_ioctl+0xbd/0xe0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:718
do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8882 Comm: syz-executor.2 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
==================================================================
---
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