KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char

KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
Status: moderation: reported on 2020/12/06 12:03
Reported-by: syzbot+ae21a27816f424fd3dda@syzkaller.appspotmail.com
First crash: 399d, last: 14d

Sample crash report:

==================================================================
BUG: KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline

write to 0xffffc90012e1b000 of 8 bytes by task 29247 on cpu 1:
 put_tty_queue drivers/tty/n_tty.c:316 [inline]
 n_tty_receive_char_inline+0x66c/0x680 drivers/tty/n_tty.c:1423
 n_tty_receive_buf_standard drivers/tty/n_tty.c:1580 [inline]
 __receive_buf drivers/tty/n_tty.c:1643 [inline]
 n_tty_receive_buf_common+0x1893/0x1e20 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 0xffffc90012e1b000 of 8 bytes by task 23429 on cpu 0:
 put_tty_queue drivers/tty/n_tty.c:315 [inline]
 n_tty_receive_char_inline+0x646/0x680 drivers/tty/n_tty.c:1423
 n_tty_receive_buf_standard drivers/tty/n_tty.c:1580 [inline]
 __receive_buf drivers/tty/n_tty.c:1643 [inline]
 n_tty_receive_buf_common+0x1893/0x1e20 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: 0x0000000000000453 -> 0x0000000000000454

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 23429 Comm: kworker/u4:4 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 (60):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/10 06:52	upstream	3dbdb38e2869	8f5a7b8c	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/07/03 18:49	upstream	3dbdb38e2869	55aa55c2	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/30 13:56	upstream	007b350a5875	84fd4c77	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/24 04:48	upstream	7266f2030eb0	fe4ab389	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/19 22:49	upstream	913ec3c22ef4	aba2b2fb	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/14 07:20	upstream	e4e453434a19	1ba81399	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/12 00:05	upstream	f21b807c3cf8	1ba81399	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/06/02 07:39	upstream	231bc5390667	0740de69	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/25 14:31	upstream	1434a3127887	3c7fef33	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/20 20:02	upstream	f01da525b3de	c560a65d	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/19 23:18	upstream	c3d0e3fd41b7	a343ba6b	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/17 13:09	upstream	d07f6ca923ea	a2eb125d	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/11 19:11	upstream	88b06399c9c7	b3c3bb8e	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/11 16:19	upstream	1140ab592e2e	ca873091	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/08 19:21	upstream	dd860052c99b	bc5434be	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/06 14:28	upstream	8404c9fbc84b	06c27ff5	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/06 09:12	upstream	a79cdfba68a1	06c27ff5	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/04 07:33	upstream	5e321ded302d	09efdd63	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/03 16:32	upstream	9ccce092fc64	ad61f371	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/02 13:15	upstream	17ae69aba89d	77e2b668	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/05/01 16:12	upstream	9f67672a817e	77e2b668	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/30 00:31	upstream	8ca5297e7e38	77e2b668	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/25 18:44	upstream	d2d09fbe33f8	36c88236	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/23 01:05	upstream	90c911ad7445	590921a5	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/22 15:31	upstream	16fc44d6387e	33c28d03	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/22 04:59	upstream	16fc44d6387e	2bc8999a	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/19 19:45	upstream	bf05bf16c76b	4285c989	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/19 13:59	upstream	bf05bf16c76b	50f523d7	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/17 13:17	upstream	9cdbf6467424	7e2b734b	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/15 03:29	upstream	7f75285ca572	fcdb12ba	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/04/12 12:26	upstream	d434405aaab7	6a81331a	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/03/25 10:10	upstream	e138138003eb	6a383ecf	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/03/20 03:53	upstream	8b12a62a4e3e	3d01c4de	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/03/14 21:15	upstream	75013c6c52d8	cc1cff8f	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/03/10 15:04	upstream	05a59d79793d	26967e35	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/03/03 21:26	upstream	f69d02e37a85	06ed56cd	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/02/22 00:23	upstream	55f62bc87347	a659b3f1	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/02/05 20:26	upstream	dd86e7fa07a3	23a562df	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/01/28 00:46	upstream	76c057c84d28	a57db36f	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/01/21 11:52	upstream	75439bc439e0	d4f4eca5	.config	log	report	info	KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_inline
ci2-upstream-kcsan-gce	2021/01/10 04:48	upstream	2ff90100ace8	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/10 11:38	upstream	a2f5ea9e314b	2a55c22b	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/29 17:19	upstream	aae5ab854e38	a0092f9d	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/08 01:40	upstream	4429f14aeea9	cba33199	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/07 14:56	upstream	659caaf65dc9	cba33199	.config	log	report	info
ci2-upstream-kcsan-gce	2020/10/27 01:25	upstream	41ba50b0572e	8b3eaf58	.config	log	report	info
ci2-upstream-kcsan-gce	2020/10/02 09:06	upstream	fcadab740480	9602ddf4	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/23 12:07	upstream	805c6d3c1921	287cd75a	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/16 20:28	upstream	5925fa68fe82	77507d02	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/15 14:52	upstream	fc4f28bb3daf	9e681632	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/12 09:18	upstream	e8878ab82545	79fb24e2	.config	log	report
ci2-upstream-kcsan-gce	2020/09/06 11:16	upstream	dd9fb9bb3340	abf9ba4f	.config	log	report
ci2-upstream-kcsan-gce	2020/09/05 01:47	upstream	c70672d8d316	abf9ba4f	.config	log	report
ci2-upstream-kcsan-gce	2020/08/15 01:38	upstream	c9c9735c46f5	5ce13532	.config	log	report
ci2-upstream-kcsan-gce	2020/07/21 14:59	upstream	4fa640dc5230	e562dd8a	.config	log	report
ci2-upstream-kcsan-gce	2020/07/07 20:25	upstream	bfe91da29bfa	08fc4ef1	.config	log	report
ci2-upstream-kcsan-gce	2020/06/29 14:35	upstream	9ebcfadb0610	df01f6fc	.config	log	report
ci2-upstream-kcsan-gce	2020/06/29 11:11	upstream	9ebcfadb0610	3ff434cc	.config	log	report
ci2-upstream-kcsan-gce	2020/06/23 18:14	upstream	3e08a95294a4	6930bbef	.config	log	report
ci2-upstream-kcsan-gce	2020/06/20 11:12	upstream	672f9255a727	c655ec77	.config	log	report