KCSAN: data-race in __send_signal / futex_wait_queue

KCSAN: data-race in __send_signal / futex_wait_queue_me (2)
Status: moderation: reported on 2020/07/04 22:52
Reported-by: syzbot+f7e11a83094efc0a1419@syzkaller.appspotmail.com
First crash: 365d, last: 17d

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __send_signal / futex_wait_queue_me				20	366d	406d	0/22	closed as invalid on 2020/06/18 14:24

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __send_signal / futex_wait_queue_me

write to 0xffff888105d490ac of 4 bytes by task 1734 on cpu 1:
 freezer_do_not_count include/linux/freezer.h:109 [inline]
 freezable_schedule include/linux/freezer.h:171 [inline]
 futex_wait_queue_me+0x198/0x260 kernel/futex.c:2606
 futex_wait+0x143/0x430 kernel/futex.c:2708
 do_futex+0x9d8/0x1ee0 kernel/futex.c:3732
 __do_sys_futex kernel/futex.c:3805 [inline]
 __se_sys_futex+0x21c/0x380 kernel/futex.c:3786
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3786
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888105d490ac of 4 bytes by task 1736 on cpu 0:
 __send_signal+0x282/0x760 kernel/signal.c:1138
 send_signal+0x281/0x390 kernel/signal.c:1284
 do_send_sig_info kernel/signal.c:1333 [inline]
 do_send_specific+0x13d/0x1c0 kernel/signal.c:3881
 do_tkill kernel/signal.c:3907 [inline]
 __do_sys_tgkill kernel/signal.c:3926 [inline]
 __se_sys_tgkill kernel/signal.c:3920 [inline]
 __x64_sys_tgkill+0x108/0x140 kernel/signal.c:3920
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00404040 -> 0x40404040

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1736 Comm: syz-fuzzer Tainted: G        W         5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (384):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/06/02 21:47	upstream	324c92e5	0740de69	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/30 23:45	upstream	8124c8a6	325a8dab	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/29 16:17	upstream	6799d4f2	325a8dab	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/29 08:35	upstream	6799d4f2	858ea628	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/28 19:25	upstream	5ff2756a	858ea628	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/28 01:47	upstream	97e5bf60	858ea628	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/27 12:46	upstream	d7c5303f	858ea628	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/26 10:16	upstream	ad9f25d3	750ce164	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/25 02:56	upstream	1434a312	3c7fef33	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/24 13:28	upstream	c4681547	3c7fef33	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/22 03:30	upstream	45af60e7	3c7fef33	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/20 17:21	upstream	f01da525	c560a65d	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/20 11:58	upstream	c3d0e3fd	c560a65d	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/17 22:16	upstream	8ac91e6c	a343ba6b	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/15 08:09	upstream	25a12987	8bdd5343	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/11 21:15	upstream	88b06399	b3c3bb8e	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/07 04:17	upstream	e4866123	06585184	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/06 15:06	upstream	8404c9fb	06585184	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/06 10:45	upstream	8404c9fb	06c27ff5	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/05 03:01	upstream	d665ea6e	06c27ff5	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/04 13:48	upstream	5e321ded	06c27ff5	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/05/03 04:55	upstream	9ccce092	77e2b668	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/30 01:00	upstream	8ca5297e	77e2b668	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/27 11:25	upstream	4a0225c3	805b5003	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/26 23:07	upstream	9f4ad9e4	8ee2dea6	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/26 09:36	upstream	9f4ad9e4	805b5003	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/25 07:30	upstream	2a1d7946	36c88236	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/23 13:04	upstream	18a3c5f7	17f0b706	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/22 23:41	upstream	90c911ad	590921a5	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/21 09:15	upstream	1fe5501b	95777977	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/19 23:08	upstream	7af08140	4285c989	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/18 09:43	upstream	c98ff1d0	7e2b734b	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/17 21:11	upstream	194cf482	7e2b734b	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/17 06:59	upstream	9cdbf646	7e2b734b	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/16 12:57	upstream	7e25f40e	7e2b734b	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/14 11:34	upstream	50987bec	3134b37f	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/13 19:34	upstream	89698bec	a184b83e	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/10 00:44	upstream	4e04e751	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/08 21:56	upstream	3fb4f979	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/08 08:42	upstream	454859c5	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/07 19:12	upstream	3a229812	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/04 22:28	upstream	e49d033b	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/03 13:20	upstream	d93a0d43	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/04/02 07:19	upstream	1678e493	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/03/31 19:15	upstream	d19cc4bf	6a81331a	.config	log	report	info	KCSAN: data-race in __send_signal / futex_wait_queue_me
ci2-upstream-kcsan-gce	2021/01/16 20:59	upstream	54c6247d	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2020/07/04 00:03	upstream	0c7d7d1f	51095195	.config	log	report
ci2-upstream-kcsan-gce	2020/06/30 22:39	upstream	7c30b859	c0383ebe	.config	log	report
ci2-upstream-kcsan-gce	2020/06/19 03:26	upstream	5e857ce6	bc258b50	.config	log	report