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BUG: KCSAN: data-race in kernfs_iop_permission / kernfs_link_sibling

read-write to 0xffff888100c9b2c0 of 8 bytes by task 5987 on cpu 1:
 kernfs_link_sibling+0x1e7/0x230 fs/kernfs/dir.c:387
 kernfs_add_one+0x260/0x390 fs/kernfs/dir.c:770
 kernfs_create_dir_ns+0x100/0x150 fs/kernfs/dir.c:1046
 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:367 [inline]
 kobject_add+0xdc/0x150 lib/kobject.c:419
 device_add+0x2ff/0xab0 drivers/base/core.c:3563
 netdev_register_kobject+0xfc/0x230 net/core/net-sysfs.c:2043
 register_netdevice+0x903/0xcd0 net/core/dev.c:10051
 vxcan_newlink+0x356/0x400 drivers/net/can/vxcan.c:249
 rtnl_newlink_create net/core/rtnetlink.c:3472 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3689 [inline]
 rtnl_newlink+0xe83/0x1600 net/core/rtnetlink.c:3702
 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6424
 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2549
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6442
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 __sys_sendto+0x257/0x310 net/socket.c:2134
 __do_sys_sendto net/socket.c:2146 [inline]
 __se_sys_sendto net/socket.c:2142 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2142
 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 0xffff888100c9b2c0 of 8 bytes by task 6141 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
 vfs_statx+0xa9/0x300 fs/stat.c:238
 vfs_fstatat fs/stat.c:276 [inline]
 __do_sys_newfstatat fs/stat.c:446 [inline]
 __se_sys_newfstatat+0x8a/0x2a0 fs/stat.c:440
 __x64_sys_newfstatat+0x55/0x60 fs/stat.c:440
 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: 0x0000000000004a25 -> 0x0000000000004a26

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6141 Comm: udevd Not tainted 6.4.0-syzkaller-12415-g8fc3b8f082cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
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