KCSAN: data-race in exit_signals / mm_update_next

KCSAN: data-race in exit_signals / mm_update_next_owner (4)
Status: moderation: reported on 2020/11/12 15:07
Reported-by: syzbot+66ebc4dba60062669bed@syzkaller.appspotmail.com
First crash: 306d, last: 2d18h

similar bugs (3):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in exit_signals / mm_update_next_owner (3)	15	326d	463d	0/22	closed as invalid on 2020/06/18 14:24
upstream	KCSAN: data-race in exit_signals / mm_update_next_owner	2	538d	543d	0/22	closed as invalid on 2019/11/19 13:24
upstream	KCSAN: data-race in exit_signals / mm_update_next_owner (2)	4	487d	513d	0/22	closed as invalid on 2020/01/09 14:13

Sample crash report:

==================================================================
BUG: KCSAN: data-race in exit_signals / mm_update_next_owner

write to 0xffff88812c2f30ec of 4 bytes by task 30929 on cpu 0:
 exit_signals+0xe1/0x4a0 kernel/signal.c:2873
 do_exit+0x194/0x1560 kernel/exit.c:781
 do_group_exit+0x19b/0x1a0 kernel/exit.c:922
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:933
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:931
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:931
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812c2f30ec of 4 bytes by task 30934 on cpu 1:
 mm_update_next_owner+0x1d9/0x520 kernel/exit.c:388
 exit_mm+0x358/0x450 kernel/exit.c:500
 do_exit+0x3ff/0x1560 kernel/exit.c:812
 do_group_exit+0x19b/0x1a0 kernel/exit.c:922
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:933
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:931
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:931
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 30934 Comm: syz-executor.5 Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (105):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/04/18 13:26	upstream	c98ff1d0	7e2b734b	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/17 08:43	upstream	9cdbf646	7e2b734b	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/16 08:01	upstream	7e25f40e	c59079a6	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/15 18:59	upstream	7f75285c	c59079a6	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/15 00:38	upstream	7f75285c	fcdb12ba	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/04 02:03	upstream	d93a0d43	6a81331a	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/01 19:51	upstream	ffd9fb54	6a81331a	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/04/01 05:57	upstream	d19cc4bf	6a81331a	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/03/30 21:10	upstream	2bb25b3a	6a81331a	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/03/25 16:41	upstream	e1381380	6a383ecf	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/03/19 17:22	upstream	8b12a62a	2af9d324	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/03/11 04:52	upstream	a74e6a01	c2ca1f2a	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/03/10 19:39	upstream	05a59d79	764067f3	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/02/14 04:50	upstream	ac30d8ce	98682e5e	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/02/02 07:42	upstream	88bb507a	e6b95f32	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/02/01 19:04	upstream	1048ba83	e6b95f32	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/31 14:36	upstream	6642d600	fc9fd31e	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/26 01:05	upstream	f8ad8187	52e37319	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/23 02:54	upstream	83d09ad4	52e37319	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/21 19:58	upstream	9791581c	d4f4eca5	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/21 05:51	upstream	75439bc4	d4f4eca5	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/20 18:48	upstream	45dfb8a5	d4f4eca5	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/18 08:05	upstream	19c329f6	fd103621	.config	log	report	info	KCSAN: data-race in exit_signals / mm_update_next_owner
ci2-upstream-kcsan-gce	2021/01/17 05:50	upstream	54c6247d	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/15 16:46	upstream	14662050	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/12 17:36	upstream	a0d54b4f	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/11 17:21	upstream	7c53f6b6	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/07 14:00	upstream	71c061d2	c104d4a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/04 19:02	upstream	e71ba945	79264ae3	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/30 17:36	upstream	139711f0	ecb8c012	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/29 07:59	upstream	dea8dcf2	8259d56c	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/29 06:41	upstream	dea8dcf2	8259d56c	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/28 05:19	upstream	5c8fe583	2242f77f	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/26 01:52	upstream	5814bc2d	821e0b09	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/25 12:42	upstream	71c5f031	b982b3ea	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/25 07:42	upstream	3913d00a	c2c1d1dd	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/23 23:23	upstream	614cb589	c2c1d1dd	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/21 17:46	upstream	e37b12e4	04201c06	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/17 17:32	upstream	accefff5	04201c06	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/10 19:11	upstream	a2f5ea9e	2a55c22b	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/08 20:57	upstream	cd796ed3	40cc414d	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/08 01:35	upstream	cd796ed3	51a9082e	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/03 08:32	upstream	3bb61aa6	8c9190ef	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/02 16:08	upstream	509a1542	eff43e99	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/30 03:10	upstream	b6505459	a0092f9d	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/27 10:03	upstream	4df91062	5018c946	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/26 02:35	upstream	fa02fcd9	3f581b43	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/12 06:49	upstream	3d5e28bf	cca87986	.config	log	report	info
ci2-upstream-kcsan-gce	2020/06/19 00:44	upstream	1b504402	3ea11d3f	.config	log	report