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BUG: KCSAN: data-race in kernfs_iop_permission / kernfs_link_sibling

read-write to 0xffff888101a3c040 of 8 bytes by task 26514 on cpu 1:
 kernfs_link_sibling+0x1e7/0x230 fs/kernfs/dir.c:387
 kernfs_add_one+0x260/0x390 fs/kernfs/dir.c:768
 kernfs_create_dir_ns+0x100/0x150 fs/kernfs/dir.c:1044
 sysfs_create_dir_ns+0xd7/0x1d0 fs/sysfs/dir.c:59
 create_dir lib/kobject.c:65 [inline]
 kobject_add_internal+0x47b/0x780 lib/kobject.c:233
 kobject_add_varg lib/kobject.c:368 [inline]
 kobject_add+0xdc/0x150 lib/kobject.c:420
 device_add+0x2ff/0xab0 drivers/base/core.c:3563
 device_add_disk+0x2b7/0x880 block/genhd.c:465
 add_disk include/linux/blkdev.h:741 [inline]
 loop_add+0x4b8/0x560 drivers/block/loop.c:2060
 loop_control_ioctl+0xc8/0x440 drivers/block/loop.c:2179
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xc9/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888101a3c040 of 8 bytes by task 2744 on cpu 0:
 kernfs_refresh_inode fs/kernfs/inode.c:181 [inline]
 kernfs_iop_permission+0x165/0x1b0 fs/kernfs/inode.c:289
 do_inode_permission fs/namei.c:461 [inline]
 inode_permission+0x184/0x300 fs/namei.c:528
 may_lookup fs/namei.c:1720 [inline]
 link_path_walk+0x19e/0x7e0 fs/namei.c:2267
 path_lookupat+0x72/0x2a0 fs/namei.c:2478
 filename_lookup+0x126/0x300 fs/namei.c:2508
 user_path_at_empty+0x42/0x110 fs/namei.c:2907
 do_readlinkat+0x92/0x210 fs/stat.c:477
 __do_sys_readlink fs/stat.c:510 [inline]
 __se_sys_readlink fs/stat.c:507 [inline]
 __x64_sys_readlink+0x47/0x50 fs/stat.c:507
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000007 -> 0x0000000000000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2744 Comm: udevd Not tainted 6.4.0-rc4-syzkaller-00031-g8b817fded42d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
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