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BUG: KCSAN: data-race in set_nlink / set_nlink

read to 0xffff888115dd9388 of 4 bytes by task 3822 on cpu 0:
 set_nlink+0x2b/0xb0 fs/inode.c:-1
 kernfs_refresh_inode fs/kernfs/inode.c:180 [inline]
 kernfs_iop_permission+0x1d3/0x210 fs/kernfs/inode.c:288
 do_inode_permission fs/namei.c:526 [inline]
 inode_permission+0x18c/0x300 fs/namei.c:593
 may_lookup fs/namei.c:1835 [inline]
 link_path_walk+0x147/0x840 fs/namei.c:2441
 path_openat+0x1b4/0x2000 fs/namei.c:4000
 do_filp_open+0x115/0x240 fs/namei.c:4031
 do_sys_openat2+0xaa/0x110 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0xf8/0x120 fs/open.c:1455
 x64_sys_call+0x1ac/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff888115dd9388 of 4 bytes by task 3004 on cpu 1:
 set_nlink+0x98/0xb0 fs/inode.c:458
 kernfs_refresh_inode fs/kernfs/inode.c:180 [inline]
 kernfs_iop_permission+0x1d3/0x210 fs/kernfs/inode.c:288
 do_inode_permission fs/namei.c:526 [inline]
 inode_permission+0x18c/0x300 fs/namei.c:593
 may_lookup fs/namei.c:1835 [inline]
 link_path_walk+0x147/0x840 fs/namei.c:2441
 path_openat+0x1b4/0x2000 fs/namei.c:4000
 do_filp_open+0x115/0x240 fs/namei.c:4031
 do_sys_openat2+0xaa/0x110 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0xf8/0x120 fs/open.c:1455
 x64_sys_call+0x1ac/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000004 -> 0x00000003

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3004 Comm: udevd Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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