KCSAN: data-race in get_signal / ptrace_check

KCSAN: data-race in get_signal / ptrace_check_attach (2)
Status: auto-closed as invalid on 2021/07/07 23:21
Reported-by: syzbot+670667eef68c9ab0c5fc@syzkaller.appspotmail.com
First crash: 405d, last: 56d

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in get_signal / ptrace_check_attach				23	410d	605d	0/22	closed as invalid on 2020/06/18 14:24

Sample crash report:

==================================================================
BUG: KCSAN: data-race in get_signal / ptrace_check_attach

write to 0xffff888152dbc498 of 8 bytes by task 1865 on cpu 0:
 ptrace_signal kernel/signal.c:2542 [inline]
 get_signal+0xbd7/0x1610 kernel/signal.c:2723
 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+0x109/0x190 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+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888152dbc498 of 8 bytes by task 1866 on cpu 1:
 ptrace_freeze_traced kernel/ptrace.c:194 [inline]
 ptrace_check_attach+0x144/0x2c0 kernel/ptrace.c:264
 __do_sys_ptrace kernel/ptrace.c:1307 [inline]
 __se_sys_ptrace+0xd8/0x1b0 kernel/ptrace.c:1277
 __x64_sys_ptrace+0x51/0x60 kernel/ptrace.c:1277
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0x0000000000010000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1866 Comm: syz-executor.3 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (194):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/06/02 23:21	upstream	324c92e5e0ee	0740de69	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/06/02 05:41	upstream	231bc5390667	032639db	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/31 07:36	upstream	8124c8a6b353	325a8dab	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/30 14:19	upstream	b90e90f40b4f	325a8dab	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/29 21:41	upstream	f956cb99b938	325a8dab	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/29 16:19	upstream	6799d4f2da49	325a8dab	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/28 23:37	upstream	5ff2756afde0	858ea628	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/28 01:49	upstream	97e5bf604b7a	858ea628	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/27 07:45	upstream	7ac3a1c1ae51	858ea628	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/26 02:02	upstream	a050a6d2b7e8	93d3a9f6	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/24 13:26	upstream	c4681547bcce	3c7fef33	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/23 11:42	upstream	4d7620341eda	3c7fef33	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/22 03:58	upstream	45af60e7ced0	3c7fef33	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/20 19:25	upstream	f01da525b3de	c560a65d	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/20 13:11	upstream	c3d0e3fd41b7	c560a65d	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/20 10:29	upstream	c3d0e3fd41b7	a343ba6b	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/19 11:01	upstream	8ac91e6c6033	a343ba6b	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/17 09:45	upstream	d07f6ca923ea	a2eb125d	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/16 02:54	upstream	c12a29ed9094	f54a5c09	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/15 15:40	upstream	25a1298726e9	93f844de	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/13 17:26	upstream	c06a2ba62fc4	ecb594cb	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/12 18:50	upstream	dbb5afad100a	ed7d41c5	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/11 19:33	upstream	88b06399c9c7	b3c3bb8e	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/10 15:58	upstream	6efb943b8616	ca873091	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/10 11:02	upstream	6efb943b8616	bc5434be	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/10 08:27	upstream	9819f682e48c	bc5434be	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/09 18:22	upstream	b741596468b0	bc5434be	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/08 00:45	upstream	1ad77a05cfae	bc5434be	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/07 04:41	upstream	e48661230cc3	06585184	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/06 18:09	upstream	8404c9fbc84b	06585184	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/05 06:25	upstream	d665ea6ea86c	06c27ff5	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/04 00:37	upstream	6f8ee8d36d07	ad61f371	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/02 11:53	upstream	17ae69aba89d	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/05/01 03:05	upstream	65c61de9d090	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/30 01:18	upstream	8ca5297e7e38	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/29 10:57	upstream	d72cd4ad4174	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/29 00:42	upstream	68a32ba14177	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/28 06:15	upstream	e359bce39d90	77e2b668	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/28 03:29	upstream	e359bce39d90	805b5003	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/27 19:09	upstream	4a0225c3d208	805b5003	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/26 11:07	upstream	9f4ad9e425a1	805b5003	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/26 02:47	upstream	d2d09fbe33f8	2a82f1b3	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/25 19:05	upstream	d2d09fbe33f8	36c88236	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/24 02:16	upstream	8db5efb83fa9	17f0b706	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/04/23 15:11	upstream	18a3c5f7abfd	17f0b706	.config	log	report	info	KCSAN: data-race in get_signal / ptrace_check_attach
ci2-upstream-kcsan-gce	2021/01/14 05:24	upstream	65f0d2414b70	269d24e8	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/20 20:44	upstream	bdcf11de8f77	9564d2e9	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/20 05:49	upstream	325d0eab4f31	53ce8104	.config	log	report	info
ci2-upstream-kcsan-gce	2020/06/19 04:15	upstream	5e857ce6eae7	bc258b50	.config	log	report