KCSAN: data-race in futex_wait_queue_me / prepare

KCSAN: data-race in futex_wait_queue_me / prepare_signal (2)
Status: moderation: reported on 2020/06/21 11:47
Reported-by: syzbot+730a2bbd66878efe4a5a@syzkaller.appspotmail.com
First crash: 302d, last: 17h04m

similar bugs (1):
Kernel	Title	Repro	Bisected	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in futex_wait_queue_me / prepare_signal			3	323d	334d	0/17	closed as invalid on 2019/11/19 13:54

Sample crash report:

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

write to 0xffff8881298d2064 of 4 bytes by task 8683 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+0x186/0x250 kernel/futex.c:2588
 futex_wait+0x145/0x390 kernel/futex.c:2690
 do_futex+0x145c/0x21c0 kernel/futex.c:3749
 __do_sys_futex kernel/futex.c:3810 [inline]
 __se_sys_futex+0x26d/0x330 kernel/futex.c:3778
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3778
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8881298d2064 of 4 bytes by task 8686 on cpu 0:
 sig_task_ignored kernel/signal.c:94 [inline]
 sig_ignored kernel/signal.c:119 [inline]
 prepare_signal+0x88d/0xdb0 kernel/signal.c:961
 __send_signal+0x64/0x7d0 kernel/signal.c:1081
 send_signal+0x398/0x3e0 kernel/signal.c:1241
 do_send_sig_info+0x9b/0xe0 kernel/signal.c:1290
 do_send_specific+0xc7/0x100 kernel/signal.c:3798
 do_tkill kernel/signal.c:3824 [inline]
 __do_sys_tgkill kernel/signal.c:3843 [inline]
 __se_sys_tgkill kernel/signal.c:3837 [inline]
 __x64_sys_tgkill+0x108/0x140 kernel/signal.c:3837
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8686 Comm: syz-fuzzer Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (344):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Maintainers
ci2-upstream-kcsan-gce	2020/09/23 19:37	upstream	805c6d3c	54289b08	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/23 08:47	upstream	805c6d3c	287cd75a	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/22 16:46	upstream	eff48dde	3e8f6c27	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/22 08:39	upstream	98477740	3e8f6c27	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/21 20:49	upstream	98477740	9e1fa68e	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/21 09:43	upstream	ba4f184e	c81d99c8	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 20:22	upstream	bdcf11de	9564d2e9	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 13:29	upstream	325d0eab	9564d2e9	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 12:07	upstream	325d0eab	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 10:00	upstream	325d0eab	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 07:57	upstream	325d0eab	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 03:56	upstream	325d0eab	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 02:06	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/20 00:53	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 21:55	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 19:38	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 17:29	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 12:27	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 10:37	upstream	eb5f95f1	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 09:13	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 07:21	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 03:40	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 01:56	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/19 00:51	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 22:30	upstream	92ab97ad	53ce8104	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 17:36	upstream	10b82d51	38962c8b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 10:58	upstream	10b82d51	38962c8b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 08:57	upstream	10b82d51	38962c8b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 06:39	upstream	4cbffc46	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 03:27	upstream	4cbffc46	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/18 01:22	upstream	4cbffc46	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 23:07	upstream	4cbffc46	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 21:36	upstream	4cbffc46	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 19:01	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 17:20	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 12:11	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 10:53	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 08:27	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 07:12	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/17 01:45	upstream	5925fa68	8247808b	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/16 23:40	upstream	5925fa68	77507d02	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/16 20:13	upstream	5925fa68	77507d02	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/16 17:16	upstream	fc4f28bb	77507d02	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/09/16 15:48	upstream	fc4f28bb	77507d02	.config	log	report	info	dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/06/20 10:25	upstream	672f9255	c655ec77	.config	log	report		dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2020/06/17 11:39	https://github.com/google/ktsan.git kcsan	7c3cd68e	b6c46f43	.config	log	report		dvhart@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de
ci2-upstream-kcsan-gce	2019/11/27 00:29	https://github.com/google/ktsan.git kcsan	ef798c30	1048481f	.config	log	report		arnd@arndb.de, christian@brauner.io, deepa.kernel@gmail.com, ebiederm@xmission.com, guro@fb.com, linux-kernel@vger.kernel.org, oleg@redhat.com