syzbot


KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special (3)

Status: auto-closed as invalid on 2021/08/13 21:23
Subsystems: serial
[Documentation on labels]
Reported-by: syzbot+c8b476f28b4240b598d0@syzkaller.appspotmail.com
First crash: 1361d, last: 983d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special (2) serial 5 1403d 1446d 0/26 auto-closed as invalid on 2020/06/19 11:58
upstream KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special serial 1 1595d 1595d 0/26 closed as invalid on 2019/11/19 13:54

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

write to 0xffffc9000f4d5018 of 8 bytes by task 15578 on cpu 1:
 echo_char_raw drivers/tty/n_tty.c:841 [inline]
 eraser drivers/tty/n_tty.c:1076 [inline]
 n_tty_receive_char_special+0x1797/0x3ac0 drivers/tty/n_tty.c:1313
 n_tty_receive_buf_fast drivers/tty/n_tty.c:1607 [inline]
 __receive_buf drivers/tty/n_tty.c:1641 [inline]
 n_tty_receive_buf_common+0xe0c/0x1e20 drivers/tty/n_tty.c:1740
 n_tty_receive_buf+0x2b/0x40 drivers/tty/n_tty.c:1769
 tiocsti drivers/tty/tty_io.c:2315 [inline]
 tty_ioctl+0x968/0x1120 drivers/tty/tty_io.c:2721
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffc9000f4d5018 of 8 bytes by task 8 on cpu 0:
 echo_char_raw drivers/tty/n_tty.c:841 [inline]
 eraser drivers/tty/n_tty.c:1078 [inline]
 n_tty_receive_char_special+0x17f6/0x3ac0 drivers/tty/n_tty.c:1313
 n_tty_receive_buf_fast drivers/tty/n_tty.c:1607 [inline]
 __receive_buf drivers/tty/n_tty.c:1641 [inline]
 n_tty_receive_buf_common+0xe0c/0x1e20 drivers/tty/n_tty.c:1740
 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1775
 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:461
 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:481 [inline]
 flush_to_ldisc+0x1c5/0x2c0 drivers/tty/tty_buffer.c:533
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276
 worker_thread+0x636/0xae0 kernel/workqueue.c:2422
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

value changed: 0x00000000000005d9 -> 0x00000000000006b7

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
==================================================================

Crashes (191):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/07/09 21:22 upstream 3dbdb38e2869 8f5a7b8c .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/09 15:51 upstream 3dbdb38e2869 281e815f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/09 06:50 upstream 3dbdb38e2869 1b20171a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/07 19:09 upstream 3dbdb38e2869 95793bce .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/07 07:46 upstream 3dbdb38e2869 4846d5c1 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/06 07:57 upstream 3dbdb38e2869 6c4484eb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/04 05:46 upstream 3dbdb38e2869 55aa55c2 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/02 12:44 upstream 3dbdb38e2869 658ebc66 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/01 23:22 upstream e058a84bfddc 658ebc66 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/01 13:36 upstream dbe69e433722 658ebc66 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/07/01 03:57 upstream df04fbe8680b 38a885d1 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/30 08:52 upstream 007b350a5875 84fd4c77 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/29 20:04 upstream c54b245d0118 a4fccb01 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/29 01:52 upstream 122fa8c58831 9d2ab5df .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/28 06:24 upstream b4b27b9eed8e 9d2ab5df .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/27 00:40 upstream 625acffd7ae2 9d2ab5df .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/22 19:43 upstream 0c18f29aae7c aba2b2fb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/18 07:31 upstream fd0aa1a4567d aba2b2fb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/17 13:28 upstream 70585216fe77 aba2b2fb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/15 11:48 upstream 009c9aa5be65 8022d7e3 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/14 10:04 upstream 009c9aa5be65 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/14 01:03 upstream e4e453434a19 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/13 20:25 upstream 8ecfa36cd4db 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/12 11:52 upstream ad347abe4a98 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/11 10:33 upstream 06af8679449d 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/10 01:13 upstream cd1245d75ce9 1ba81399 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/09 20:47 upstream 368094df48e6 84fe5d96 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/08 02:30 upstream 614124bea77e b718257f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/07 14:44 upstream 614124bea77e e59537be .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/06 21:27 upstream decad3e1d1ed 500c2339 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/06 00:48 upstream f5b6eb1e0182 500c2339 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/05 11:01 upstream 9d32fa5d74b1 500c2339 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/04 10:27 upstream f88cd3fb9df2 966a236b .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/02 21:29 upstream 324c92e5e0ee 0740de69 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/02 07:45 upstream 231bc5390667 0740de69 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/02 05:00 upstream 231bc5390667 032639db .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/06/01 17:52 upstream c2131f7e73c9 032639db .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/05/31 10:16 upstream 8124c8a6b353 032639db .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/05/29 19:53 upstream f956cb99b938 325a8dab .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/05/27 12:30 upstream d7c5303fbc8a 858ea628 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/05/27 03:26 upstream 7ac3a1c1ae51 858ea628 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/05/26 08:44 upstream ad9f25d33860 93d3a9f6 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in n_tty_receive_char_special / n_tty_receive_char_special
2021/01/16 21:09 upstream 54c6247d06f1 65a7a854 .config console log report info ci2-upstream-kcsan-gce
2020/11/27 22:05 upstream 85a2c56cb445 486f93ef .config console log report info ci2-upstream-kcsan-gce
2020/06/27 02:51 upstream 1590a2e1c681 ffec44b5 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.