KCSAN: data-race in attach_to_pi_owner / futex_wait_queue

KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (6)
Status: auto-closed as invalid on 2021/01/21 10:32
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 227d, last: 227d

similar bugs (6):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (4)	3	372d	404d	0/22	auto-closed as invalid on 2020/08/28 22:57
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (2)	2	604d	605d	0/22	auto-closed as invalid on 2020/02/14 17:46
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me	1	633d	633d	0/22	closed as invalid on 2019/11/19 13:54
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (3)	3	473d	531d	0/22	auto-closed as invalid on 2020/06/18 14:03
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (5)	1	281d	281d	0/22	auto-closed as invalid on 2020/11/28 10:56
upstream	KCSAN: data-race in attach_to_pi_owner / futex_wait_queue_me (7)	1	86d	86d	0/22	auto-closed as invalid on 2021/06/11 04:30

Sample crash report:

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

read-write to 0xffff88801fda102c of 4 bytes by task 32376 on cpu 0:
 freezer_do_not_count include/linux/freezer.h:109 [inline]
 freezable_schedule include/linux/freezer.h:171 [inline]
 futex_wait_queue_me+0x17e/0x240 kernel/futex.c:2602
 futex_wait+0x145/0x3d0 kernel/futex.c:2704
 do_futex+0x105a/0x20c0 kernel/futex.c:3763
 __do_sys_futex kernel/futex.c:3826 [inline]
 __se_sys_futex+0x2a8/0x390 kernel/futex.c:3792
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3792
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88801fda102c of 4 bytes by task 32393 on cpu 1:
 attach_to_pi_owner+0x64/0x480 kernel/futex.c:1215
 futex_lock_pi_atomic+0x338/0x4f0 kernel/futex.c:1420
 futex_lock_pi+0x2bf/0x880 kernel/futex.c:2797
 do_futex+0x1fc/0x20c0 kernel/futex.c:3776
 __do_sys_futex kernel/futex.c:3826 [inline]
 __se_sys_futex+0x2a8/0x390 kernel/futex.c:3792
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3792
 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: 1 PID: 32393 Comm: syz-executor.4 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2020/12/17 10:27	upstream	accefff5b547	04201c06	.config	log	report			info