KCSAN: data-race in do_signal_stop / prepare

KCSAN: data-race in do_signal_stop / prepare_signal
Status: moderation: reported on 2020/01/24 11:57
Reported-by: syzbot+60abfb3e5fb112d5a211@syzkaller.appspotmail.com
First crash: 546d, last: 23h04m

Sample crash report:

==================================================================
BUG: KCSAN: data-race in do_signal_stop / prepare_signal

write to 0xffff88812893a02c of 4 bytes by task 8240 on cpu 0:
 freezer_count include/linux/freezer.h:121 [inline]
 freezable_schedule include/linux/freezer.h:173 [inline]
 do_signal_stop+0x591/0x710 kernel/signal.c:2396
 get_signal+0xb31/0x15d0 kernel/signal.c:2631
 arch_do_signal_or_restart+0x2a/0x220 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x104/0x170 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x40/0x50 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812893a02c of 4 bytes by task 1770 on cpu 1:
 sig_task_ignored kernel/signal.c:94 [inline]
 sig_ignored kernel/signal.c:119 [inline]
 prepare_signal+0x872/0xd80 kernel/signal.c:962
 __send_signal+0x64/0x760 kernel/signal.c:1082
 send_signal+0x38e/0x3d0 kernel/signal.c:1242
 do_send_sig_info kernel/signal.c:1291 [inline]
 group_send_sig_info+0xe8/0x140 kernel/signal.c:1414
 kill_pid_info kernel/signal.c:1448 [inline]
 kill_proc_info kernel/signal.c:1465 [inline]
 kill_something_info kernel/signal.c:1562 [inline]
 __do_sys_kill kernel/signal.c:3691 [inline]
 __se_sys_kill+0xeb/0x400 kernel/signal.c:3685
 __x64_sys_kill+0x2d/0x40 kernel/signal.c:3685
 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: 1770 Comm: syz-executor.5 Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (322):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/04/22 12:47	upstream	16fc44d6	33c28d03	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/17 07:24	upstream	9cdbf646	7e2b734b	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/12 22:59	upstream	89698bec	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/11 19:49	upstream	7d900724	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/10 15:02	upstream	d4961772	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/02 08:26	upstream	1678e493	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/04/01 18:39	upstream	ffd9fb54	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/31 19:41	upstream	d19cc4bf	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/31 06:59	upstream	5e46d1b7	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/29 21:24	upstream	1e43c377	6a81331a	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/23 15:59	upstream	84196390	e613994b	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/22 18:45	upstream	0d02ec6b	8092f30d	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/19 21:17	upstream	8b12a62a	3d01c4de	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/18 03:36	upstream	6417f031	fdb2bb2c	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/12 10:28	upstream	f78d76e7	429d8a6b	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/09 17:28	upstream	144c79ef	26967e35	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/04 07:40	upstream	f69d02e3	d7e4e604	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/03/03 23:51	upstream	f69d02e3	06ed56cd	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/14 00:40	upstream	ac30d8ce	98682e5e	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/10 14:06	upstream	e0756cfc	9c8b8541	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/08 13:09	upstream	92bf2261	2ce644fc	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/06 12:12	upstream	1e0d27fc	0655e081	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/06 03:56	upstream	1e0d27fc	23a562df	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/02 23:59	upstream	3aaf0a27	624dad51	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/02/01 14:06	upstream	1048ba83	e6b95f32	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/01/30 22:33	upstream	8c947645	fc9fd31e	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/01/19 00:16	upstream	1e2a199f	63631df1	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/01/18 04:28	upstream	19c329f6	fd103621	.config	log	report	info	KCSAN: data-race in do_signal_stop / prepare_signal
ci2-upstream-kcsan-gce	2021/01/15 20:09	upstream	5ee88057	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/15 00:51	upstream	14662050	468dbb55	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/14 18:59	upstream	65f0d241	468dbb55	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/13 21:39	upstream	65f0d241	a945f0a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/13 11:24	upstream	e609571b	a945f0a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/12 19:14	upstream	e609571b	0cdd6185	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/11 11:26	upstream	7c53f6b6	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/10 21:28	upstream	0653161f	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/09 10:27	upstream	996e435f	a6c52263	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/08 21:21	upstream	6279d812	c104d4a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/04 19:50	upstream	36bbbd0e	79264ae3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/04 04:39	upstream	e71ba945	79264ae3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/02 00:18	upstream	eda809ae	79264ae3	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/31 14:57	upstream	f6e1ea19	79264ae3	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/29 08:26	upstream	dea8dcf2	8259d56c	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/29 02:51	upstream	c76e02c5	8259d56c	.config	log	report	info
ci2-upstream-kcsan-gce	2020/01/23 15:07	https://github.com/google/ktsan.git kcsan	245a4300	11ebf937	.config	log	report
ci2-upstream-kcsan-gce	2020/01/20 11:17	https://github.com/google/ktsan.git kcsan	245a4300	c40da18c	.config	log	report
ci2-upstream-kcsan-gce	2019/10/24 19:31	https://github.com/google/ktsan.git kcsan	05f22368	d01bb02a	.config	log	report