syzbot


KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common (2)

Status: auto-closed as invalid on 2021/11/10 16:29
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 444d, last: 422d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common (4) 1 219d 219d 0/24 auto-closed as invalid on 2022/06/02 02:02
upstream KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common (5) 1 138d 138d 0/24 auto-closed as invalid on 2022/08/21 08:44
upstream KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common 1 1031d 1031d 0/24 auto-closed as invalid on 2020/04/15 15:43
upstream KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common (3) 4 291d 341d 0/24 auto-closed as invalid on 2022/03/21 13:14
upstream KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common (6) 1 62d 62d 0/24 auto-obsoleted due to no activity on 2022/11/05 11:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common

write to 0xffffc900009d505c of 1 bytes by task 15381 on cpu 1:
 n_tty_receive_buf_common+0x370/0x4e70 drivers/tty/n_tty.c:1664
 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1709
 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:471
 paste_selection+0x215/0x300 drivers/tty/vt/selection.c:408
 tioclinux+0xe5/0x450 drivers/tty/vt/vt.c:3204
 vt_ioctl+0x27f/0x2150 drivers/tty/vt/vt_ioctl.c:762
 tty_ioctl+0xa8e/0x11a0 drivers/tty/tty_io.c:2805
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffc900009d505c of 1 bytes by task 27830 on cpu 0:
 n_tty_kick_worker+0x2d/0x160 drivers/tty/n_tty.c:205
 n_tty_read+0x4a7/0x10c0 drivers/tty/n_tty.c:2094
 iterate_tty_read drivers/tty/tty_io.c:868 [inline]
 tty_read+0x199/0x420 drivers/tty/tty_io.c:944
 call_read_iter include/linux/fs.h:2157 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0x66c/0x750 fs/read_write.c:485
 ksys_read+0xd9/0x190 fs/read_write.c:623
 __do_sys_read fs/read_write.c:633 [inline]
 __se_sys_read fs/read_write.c:631 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27830 Comm: agetty Not tainted 5.15.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/10/06 16:21 upstream 60a9483534ed 0a63fd36 .config log report info KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common
ci2-upstream-kcsan-gce 2021/10/03 16:00 upstream 7b66f4393ad4 db0f5787 .config log report info KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common
ci2-upstream-kcsan-gce 2021/09/22 04:49 upstream 92477dd1faa6 169724fe .config log report info KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common
ci2-upstream-kcsan-gce 2021/09/14 17:15 upstream 1619b69edce1 07e953c1 .config log report info KCSAN: data-race in n_tty_kick_worker / n_tty_receive_buf_common
* Struck through repros no longer work on HEAD.