KCSAN: data-race in shmem_mknod / vfs_getattr

KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
Status: moderation: reported on 2020/08/02 14:16
Reported-by: syzbot+7a06fc3f1c23166f7c87@syzkaller.appspotmail.com
First crash: 529d, last: 15h34m

Sample crash report:

==================================================================
BUG: KCSAN: data-race in shmem_mknod / vfs_getattr_nosec

write to 0xffff888103c79148 of 8 bytes by task 12680 on cpu 1:
 shmem_mknod+0xdc/0x170 mm/shmem.c:2840
 shmem_create+0x2f/0x40 mm/shmem.c:2891
 lookup_open fs/namei.c:3280 [inline]
 open_last_lookups fs/namei.c:3350 [inline]
 path_openat+0xd2c/0x1eb0 fs/namei.c:3556
 do_filp_open+0x105/0x220 fs/namei.c:3586
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1212
 do_sys_open fs/open.c:1228 [inline]
 __do_sys_openat fs/open.c:1244 [inline]
 __se_sys_openat fs/open.c:1239 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1239
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888103c79148 of 8 bytes by task 12678 on cpu 0:
 i_size_read include/linux/fs.h:891 [inline]
 generic_fillattr fs/stat.c:53 [inline]
 vfs_getattr_nosec+0x242/0x2f0 fs/stat.c:126
 vfs_getattr fs/stat.c:160 [inline]
 vfs_statx+0x138/0x2a0 fs/stat.c:225
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:412 [inline]
 __se_sys_newfstatat+0x63/0x260 fs/stat.c:406
 __x64_sys_newfstatat+0x51/0x60 fs/stat.c:406
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000001be4 -> 0x0000000000001bf8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12678 Comm: udevd Tainted: G        W         5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (851):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/11/29 11:48	upstream	d58071a8a76d	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/29 00:38	upstream	d06c942efea4	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/28 09:27	upstream	3498e7f2bb41	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/27 19:15	upstream	741392771338	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/26 23:03	upstream	c5c17547b778	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/26 09:24	upstream	a4849f6000e2	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/25 19:50	upstream	b501b85957de	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/25 17:53	upstream	5f53fa508db0	63eeac02	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/24 19:18	upstream	5f53fa508db0	545ab074	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/24 03:20	upstream	5d9f4cf36721	545ab074	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/22 13:56	upstream	136057256686	545ab074	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/22 12:42	upstream	136057256686	4eb20a4e	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/22 08:22	upstream	40c93d7fff6f	4eb20a4e	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/21 09:01	upstream	923dcc5eb0c1	4eb20a4e	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/20 20:48	upstream	61564e7b3abc	4eb20a4e	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/20 03:24	upstream	a90af8f15bdc	4eb20a4e	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/19 17:45	upstream	4c388a8e740d	3a9d0024	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/19 11:48	upstream	4c388a8e740d	31a30fc0	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/18 23:14	upstream	6fdf886424cf	31a30fc0	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/18 14:31	upstream	42eb8fdac2fc	31a30fc0	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/18 09:59	upstream	42eb8fdac2fc	cafff8b6	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/17 23:23	upstream	ee1703cda8dc	cafff8b6	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/16 22:55	upstream	8ab774587903	cafff8b6	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/16 10:30	upstream	8ab774587903	600426bd	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/15 16:06	upstream	8ab774587903	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/15 02:17	upstream	ce49bfc8d037	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/14 08:48	upstream	c8c109546a19	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/13 19:53	upstream	a9b9669d9822	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/13 06:43	upstream	66f4beaa6c1d	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/12 13:48	upstream	5833291ab6de	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/12 04:04	upstream	ca2ef2d9f2aa	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/11 07:57	upstream	debe436e77c7	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/10 20:45	upstream	89d714ab6043	75b04091	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/10 01:30	upstream	cb690f5238d7	55fa030c	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/09 20:42	upstream	d2f38a3c6507	59bcaf9a	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/09 06:01	upstream	e851dfae4371	8ab17e57	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/08 20:03	upstream	e851dfae4371	d29682f1	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/08 12:43	upstream	6b75d88fa81b	d29682f1	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/08 03:45	upstream	6b75d88fa81b	4c1be0be	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/07 11:41	upstream	b5013d084e03	4c1be0be	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/06 22:35	upstream	512b7931ad05	4c1be0be	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/11/05 20:34	upstream	fe91c4725aee	4c1be0be	.config	log	report	info	KCSAN: data-race in shmem_mknod / vfs_getattr_nosec
ci2-upstream-kcsan-gce	2021/01/17 14:20	upstream	0da0a8a0a0e1	813be542	.config	log	report	info
ci2-upstream-kcsan-gce	2020/08/01 04:31	upstream	7dc6fd0f3b84	8df85ed9	.config	log	report
ci2-upstream-kcsan-gce	2020/07/29 14:09	upstream	6ba1b005ffc3	19a8de55	.config	log	report
ci2-upstream-kcsan-gce	2020/06/18 15:50	upstream	1b5044021070	3ea11d3f	.config	log	report