KCSAN: data-race in list_lru_add / list_lru_count

KCSAN: data-race in list_lru_add / list_lru_count_node (5)
Status: auto-closed as invalid on 2021/09/03 02:37
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 110d, last: 89d

similar bugs (4):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in list_lru_add / list_lru_count_node (3)	3	270d	296d	0/22	auto-closed as invalid on 2021/02/28 22:07
upstream	KCSAN: data-race in list_lru_add / list_lru_count_node (2)	1	488d	488d	0/22	auto-closed as invalid on 2020/07/25 12:43
upstream	KCSAN: data-race in list_lru_add / list_lru_count_node	1	558d	558d	0/22	auto-closed as invalid on 2020/06/18 13:43
upstream	KCSAN: data-race in list_lru_add / list_lru_count_node (4)	5	158d	170d	0/22	auto-closed as invalid on 2021/06/20 16:41

Sample crash report:

==================================================================
BUG: KCSAN: data-race in list_lru_add / list_lru_count_node

write to 0xffff8881011fcba8 of 8 bytes by task 1823 on cpu 0:
 list_lru_add+0x26d/0x2c0 mm/list_lru.c:130
 d_lru_add fs/dcache.c:406 [inline]
 retain_dentry+0x226/0x260 fs/dcache.c:660
 dput+0x3d/0x360 fs/dcache.c:883
 done_path_create fs/namei.c:3650 [inline]
 do_mkdirat+0x128/0x200 fs/namei.c:3851
 __do_sys_mkdir fs/namei.c:3866 [inline]
 __se_sys_mkdir fs/namei.c:3864 [inline]
 __x64_sys_mkdir+0x32/0x40 fs/namei.c:3864
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881011fcba8 of 8 bytes by task 1822 on cpu 1:
 list_lru_count_node+0x28/0x30 mm/list_lru.c:195
 list_lru_count include/linux/list_lru.h:132 [inline]
 shrink_dcache_sb+0x1ed/0x2d0 fs/dcache.c:1297
 reconfigure_super+0x2aa/0x4f0 fs/super.c:889
 do_remount fs/namespace.c:2639 [inline]
 path_mount+0x1442/0x1ce0 fs/namespace.c:3227
 do_mount fs/namespace.c:3248 [inline]
 __do_sys_mount fs/namespace.c:3456 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3433
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3433
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1822 Comm: syz-executor.5 Not tainted 5.14.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
EXT4-fs error (device sda1): ext4_remount:5937: comm syz-executor.5: Abort forced by user
EXT4-fs (sda1): Remounting filesystem read-only

Crashes (3):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/24 16:10	upstream	f0fddcec6b62	4d1b57d4	.config	log	report	info	KCSAN: data-race in list_lru_add / list_lru_count_node
ci2-upstream-kcsan-gce	2021/07/15 11:00	upstream	8096acd7442e	b9a2f64e	.config	log	report	info	KCSAN: data-race in list_lru_add / list_lru_count_node
ci2-upstream-kcsan-gce	2021/07/03 21:37	upstream	3dbdb38e2869	55aa55c2	.config	log	report	info	KCSAN: data-race in list_lru_add / list_lru_count_node