syzbot


KCSAN: data-race in __tty_hangup / tty_hung_up_p (6)

Status: auto-closed as invalid on 2021/11/19 04:32
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 407d, last: 407d
similar bugs (8):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (4) 3 549d 595d 0/24 auto-closed as invalid on 2021/06/30 05:54
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (8) 1 316d 316d 0/24 auto-closed as invalid on 2022/02/17 20:31
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (9) 1 149d 149d 0/24 auto-closed as invalid on 2022/08/03 23:21
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p 4 1071d 1090d 0/24 auto-closed as invalid on 2020/02/29 07:50
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (3) 1 659d 659d 0/24 auto-closed as invalid on 2021/03/12 04:16
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (7) 1 366d 366d 0/24 auto-closed as invalid on 2021/12/30 10:24
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (5) 1 497d 497d 0/24 auto-closed as invalid on 2021/08/21 03:58
upstream KCSAN: data-race in __tty_hangup / tty_hung_up_p (2) 1 841d 841d 0/24 auto-closed as invalid on 2020/09/11 06:18

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __tty_hangup / tty_hung_up_p

write to 0xffff888109132d28 of 8 bytes by task 22570 on cpu 0:
 __tty_hangup+0x247/0x650 drivers/tty/tty_io.c:630
 tty_vhangup+0x13/0x20 drivers/tty/tty_io.c:711
 pty_close+0x27b/0x2a0 drivers/tty/pty.c:79
 tty_release+0x255/0xa10 drivers/tty/tty_io.c:1771
 __fput+0x295/0x520 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888109132d28 of 8 bytes by task 22572 on cpu 1:
 tty_hung_up_p+0x1c/0x40 drivers/tty/tty_io.c:760
 n_tty_write+0x2b4/0xaf0 drivers/tty/n_tty.c:2282
 do_tty_write drivers/tty/tty_io.c:1038 [inline]
 file_tty_write+0x409/0x660 drivers/tty/tty_io.c:1110
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1131
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x7bc/0x900 fs/read_write.c:594
 ksys_write+0xd9/0x190 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:656
 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: 0xffffffff8308b4d8 -> 0xffffffff8308b3d8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22572 Comm: syz-executor.2 Not tainted 5.15.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/10/15 04:32 upstream 26d657410983 7aa5fe41 .config log report info KCSAN: data-race in __tty_hangup / tty_hung_up_p
* Struck through repros no longer work on HEAD.