KCSAN: data-race in ___d_drop / __d

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in ___d_drop / __d_lookup (3) fs	6				1	263d	263d	0/29	auto-obsoleted due to no activity on 2025/03/16 02:22
upstream	KCSAN: data-race in ___d_drop / __d_lookup (2) fs	6				2	625d	658d	0/29	auto-obsoleted due to no activity on 2024/02/27 04:23

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BUG: KCSAN: data-race in ___d_drop / __d_lookup

write to 0xffff88810a1493d0 of 8 bytes by task 2243 on cpu 0:
 __hlist_bl_del include/linux/list_bl.h:128 [inline]
 ___d_drop+0x106/0x220 fs/dcache.c:500
 __d_drop fs/dcache.c:507 [inline]
 d_invalidate+0x51/0x1c0 fs/dcache.c:1730
 simple_recursive_removal+0x27d/0x4f0 fs/libfs.c:286
 debugfs_remove+0x49/0x70 fs/debugfs/inode.c:765
 nsim_dev_port_debugfs_exit drivers/net/netdevsim/dev.c:426 [inline]
 __nsim_dev_port_del+0xe5/0x100 drivers/net/netdevsim/dev.c:1426
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1437 [inline]
 nsim_dev_reload_destroy+0x1a6/0x2c0 drivers/net/netdevsim/dev.c:1658
 nsim_dev_reload_down+0x77/0x90 drivers/net/netdevsim/dev.c:965
 devlink_reload+0xad/0x390 net/devlink/dev.c:362
 devlink_nl_cmd_reload+0x78d/0x8f0 net/devlink/dev.c:485
 genl_family_rcv_msg_doit net/netlink/genetlink.c:970 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1050 [inline]
 genl_rcv_msg+0x67d/0x720 net/netlink/genetlink.c:1067
 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2549
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1078
 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_sendmsg+0x37c/0x4d0 net/socket.c:2494
 ___sys_sendmsg net/socket.c:2548 [inline]
 __sys_sendmsg+0x1e9/0x270 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x46/0x50 net/socket.c:2584
 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 0xffff88810a1493d0 of 8 bytes by task 2764 on cpu 1:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:335 [inline]
 __d_lookup+0x10e/0x380 fs/dcache.c:2491
 lookup_fast+0x4c/0x290 fs/namei.c:1648
 walk_component fs/namei.c:1994 [inline]
 link_path_walk+0x3f4/0x7e0 fs/namei.c:2325
 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: 0xffff88810a2d3308 -> 0xffff888237aa8400

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2764 Comm: udevd Not tainted 6.5.0-rc1-syzkaller-00259-g831fe284d827 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
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