KCSAN: data-race in inode_permission / inode

KCSAN: data-race in inode_permission / inode_permission (2)
Status: auto-closed as invalid on 2020/08/17 22:52
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 460d, last: 460d

similar bugs (4):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in inode_permission / inode_permission (4)	1	348d	313d	0/22	auto-closed as invalid on 2020/12/21 11:15
upstream	KCSAN: data-race in inode_permission / inode_permission (5)	12	139d	248d	0/22	auto-closed as invalid on 2021/07/04 17:17
upstream	KCSAN: data-race in inode_permission / inode_permission	27	562d	723d	0/22	auto-closed as invalid on 2020/06/11 10:47
upstream	KCSAN: data-race in inode_permission / inode_permission (3)	1	422d	422d	0/22	auto-closed as invalid on 2020/09/24 20:47

Sample crash report:

==================================================================
BUG: KCSAN: data-race in inode_permission / inode_permission

write to 0xffff8880b89e1aaa of 2 bytes by task 31167 on cpu 0:
 do_inode_permission fs/namei.c:402 [inline]
 inode_permission+0x314/0x330 fs/namei.c:463
 may_lookup fs/namei.c:1569 [inline]
 link_path_walk+0x14a/0x730 fs/namei.c:2125
 path_openat+0x199/0x20e0 fs/namei.c:3356
 do_filp_open+0xbd/0x1d0 fs/namei.c:3387
 do_sys_openat2+0x33c/0x4a0 fs/open.c:1179
 do_sys_open fs/open.c:1195 [inline]
 ksys_open include/linux/syscalls.h:1388 [inline]
 __do_sys_open fs/open.c:1201 [inline]
 __se_sys_open fs/open.c:1199 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1199
 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880b89e1aaa of 2 bytes by task 31154 on cpu 1:
 do_inode_permission fs/namei.c:396 [inline]
 inode_permission+0x41/0x330 fs/namei.c:463
 may_lookup fs/namei.c:1569 [inline]
 link_path_walk+0x14a/0x730 fs/namei.c:2125
 path_openat+0x199/0x20e0 fs/namei.c:3356
 do_filp_open+0xbd/0x1d0 fs/namei.c:3387
 do_sys_openat2+0x33c/0x4a0 fs/open.c:1179
 do_sys_open fs/open.c:1195 [inline]
 ksys_open include/linux/syscalls.h:1388 [inline]
 __do_sys_open fs/open.c:1201 [inline]
 __se_sys_open fs/open.c:1199 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1199
 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 31154 Comm: systemd-udevd Not tainted 5.8.0-rc5-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	2020/07/13 22:43	upstream	11ba468877bb	ce4c95b3	.config	log	report