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BUG: KCSAN: data-race in set_nlink / set_nlink

read to 0xffff8881072d04b8 of 4 bytes by task 2974 on cpu 0:
 set_nlink+0x29/0xb0 fs/inode.c:-1
 kernfs_refresh_inode fs/kernfs/inode.c:179 [inline]
 kernfs_iop_permission+0x1e5/0x220 fs/kernfs/inode.c:287
 do_inode_permission fs/namei.c:583 [inline]
 inode_permission+0x2b4/0x3c0 fs/namei.c:653
 lookup_inode_permission_may_exec fs/namei.c:-1 [inline]
 may_lookup fs/namei.c:1961 [inline]
 link_path_walk+0x881/0xde0 fs/namei.c:2604
 path_lookupat+0x53/0x4c0 fs/namei.c:2812
 filename_lookup+0x18f/0x390 fs/namei.c:2842
 vfs_statx+0x96/0x170 fs/stat.c:357
 vfs_fstatat+0x118/0x170 fs/stat.c:377
 __do_sys_newfstatat fs/stat.c:542 [inline]
 __se_sys_newfstatat+0x55/0x3e0 fs/stat.c:536
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:536
 x64_sys_call+0xee6/0x2550 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff8881072d04b8 of 4 bytes by task 6962 on cpu 1:
 set_nlink+0x99/0xb0 fs/inode.c:449
 kernfs_refresh_inode fs/kernfs/inode.c:179 [inline]
 kernfs_iop_permission+0x1e5/0x220 fs/kernfs/inode.c:287
 do_inode_permission fs/namei.c:583 [inline]
 inode_permission+0x2b4/0x3c0 fs/namei.c:653
 lookup_inode_permission_may_exec fs/namei.c:-1 [inline]
 may_lookup fs/namei.c:1961 [inline]
 link_path_walk+0x881/0xde0 fs/namei.c:2604
 path_openat+0x142/0x11c0 fs/namei.c:5006
 do_file_open+0x16c/0x290 fs/namei.c:5039
 do_sys_openat2+0xa1/0x140 fs/open.c:1442
 do_sys_open fs/open.c:1448 [inline]
 __do_sys_openat fs/open.c:1464 [inline]
 __se_sys_openat fs/open.c:1459 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1459
 x64_sys_call+0x1f72/0x2550 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000008 -> 0x00000009

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6962 Comm: udevd Tainted: G                   Y syzkaller #0 PREEMPT(lazy) 
Tainted: [Y]=FORCED_BIND
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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