KCSAN: data-race in d_invalidate / fast

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in d_invalidate / fast_dput (4) fs	6	4	261d	301d	0/29	auto-obsoleted due to no activity on 2025/01/05 15:13
upstream	KCSAN: data-race in d_invalidate / fast_dput (2) fs	6	1	420d	420d	0/29	auto-obsoleted due to no activity on 2024/07/09 14:03
upstream	KCSAN: data-race in d_invalidate / fast_dput (3) fs	6	2	347d	357d	0/29	auto-obsoleted due to no activity on 2024/09/21 03:13
upstream	KCSAN: data-race in d_invalidate / fast_dput fs	6	4	493d	540d	0/29	auto-obsoleted due to no activity on 2024/04/27 15:57

==================================================================
BUG: KCSAN: data-race in d_invalidate / fast_dput

write to 0xffff88811a980310 of 8 bytes by task 5415 on cpu 0:
 __d_drop fs/dcache.c:575 [inline]
 d_invalidate+0x5b/0x1c0 fs/dcache.c:1651
 lookup_fast+0x296/0x320 fs/namei.c:1782
 walk_component fs/namei.c:2134 [inline]
 link_path_walk+0x4ba/0x900 fs/namei.c:2506
 path_openat+0x1de/0x2170 fs/namei.c:4051
 do_filp_open+0x109/0x230 fs/namei.c:4082
 do_sys_openat2+0xa6/0x110 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1463
 x64_sys_call+0x1af/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811a980310 of 8 bytes by task 4841 on cpu 1:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:359 [inline]
 retain_dentry fs/dcache.c:752 [inline]
 fast_dput+0x5f/0x2c0 fs/dcache.c:848
 dput+0x24/0xd0 fs/dcache.c:905
 handle_mounts fs/namei.c:1640 [inline]
 step_into+0x5b2/0x820 fs/namei.c:1976
 walk_component fs/namei.c:2144 [inline]
 link_path_walk+0x571/0x900 fs/namei.c:2506
 path_openat+0x1de/0x2170 fs/namei.c:4051
 do_filp_open+0x109/0x230 fs/namei.c:4082
 do_sys_openat2+0xa6/0x110 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1463
 x64_sys_call+0x1af/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff8882375629f0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4841 Comm: udevd Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================