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BUG: KCSAN: data-race in generic_permission / kernfs_refresh_inode

read to 0xffff888125496258 of 2 bytes by task 7897 on cpu 0:
 acl_permission_check fs/namei.c:295 [inline]
 generic_permission+0x36/0x410 fs/namei.c:339
 kernfs_iop_permission+0x7d/0xa0 fs/kernfs/inode.c:286
 do_inode_permission fs/namei.c:384 [inline]
 inode_permission+0x241/0x370 fs/namei.c:449
 may_lookup fs/namei.c:1696 [inline]
 link_path_walk.part.0+0x622/0xa90 fs/namei.c:2071
 link_path_walk fs/namei.c:2256 [inline]
 path_lookupat.isra.0+0x77/0x5a0 fs/namei.c:2304
 filename_lookup+0x145/0x2b0 fs/namei.c:2335
 user_path_at_empty+0x4c/0x70 fs/namei.c:2615
 user_path_at include/linux/namei.h:49 [inline]
 vfs_statx+0xd9/0x190 fs/stat.c:187
 vfs_stat include/linux/fs.h:3249 [inline]
 __do_sys_newstat+0x51/0xb0 fs/stat.c:341
 __se_sys_newstat fs/stat.c:337 [inline]
 __x64_sys_newstat+0x3a/0x50 fs/stat.c:337
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff888125496258 of 2 bytes by task 3994 on cpu 1:
 kernfs_refresh_inode+0x42/0x140 fs/kernfs/inode.c:172
 kernfs_iop_permission+0x66/0xa0 fs/kernfs/inode.c:283
 do_inode_permission fs/namei.c:384 [inline]
 inode_permission+0x241/0x370 fs/namei.c:449
 may_lookup fs/namei.c:1696 [inline]
 link_path_walk.part.0+0x622/0xa90 fs/namei.c:2071
 link_path_walk fs/namei.c:2256 [inline]
 path_lookupat.isra.0+0x77/0x5a0 fs/namei.c:2304
 filename_lookup+0x145/0x2b0 fs/namei.c:2335
 user_path_at_empty+0x4c/0x70 fs/namei.c:2615
 do_readlinkat+0x84/0x220 fs/stat.c:399
 __do_sys_readlink fs/stat.c:432 [inline]
 __se_sys_readlink fs/stat.c:429 [inline]
 __x64_sys_readlink+0x51/0x70 fs/stat.c:429
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3994 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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