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BUG: KCSAN: data-race in rwsem_down_write_slowpath / rwsem_down_write_slowpath

write to 0xffffc90004c87a10 of 1 bytes by task 6329 on cpu 1:
 rwsem_try_write_lock kernel/locking/rwsem.c:676 [inline]
 rwsem_down_write_slowpath+0x3eb/0xab0 kernel/locking/rwsem.c:1189
 __down_write_common kernel/locking/rwsem.c:1347 [inline]
 __down_write kernel/locking/rwsem.c:1356 [inline]
 down_write+0xad/0xc0 kernel/locking/rwsem.c:1632
 kernfs_add_one+0x5a/0x350 fs/kernfs/dir.c:825
 __kernfs_create_file+0x145/0x180 fs/kernfs/file.c:1079
 sysfs_add_file_mode_ns+0x132/0x1b0 fs/sysfs/file.c:316
 create_files fs/sysfs/group.c:82 [inline]
 internal_create_group+0x43e/0x9e0 fs/sysfs/group.c:189
 internal_create_groups fs/sysfs/group.c:229 [inline]
 sysfs_create_groups+0x3f/0xf0 fs/sysfs/group.c:255
 setup_gid_attrs drivers/infiniband/core/sysfs.c:1118 [inline]
 ib_setup_port_attrs+0xee7/0x1480 drivers/infiniband/core/sysfs.c:1394
 add_one_compat_dev+0x297/0x390 drivers/infiniband/core/device.c:1002
 add_compat_devs drivers/infiniband/core/device.c:1060 [inline]
 enable_device_and_get+0x1cd/0x260 drivers/infiniband/core/device.c:1381
 ib_register_device+0x906/0xa80 drivers/infiniband/core/device.c:1503
 rxe_register_device+0x175/0x190 drivers/infiniband/sw/rxe/rxe_verbs.c:1549
 rxe_add+0x8e2/0x900 drivers/infiniband/sw/rxe/rxe.c:217
 rxe_net_add+0x62/0xb0 drivers/infiniband/sw/rxe/rxe_net.c:625
 rxe_newlink+0xdd/0x1a0 drivers/infiniband/sw/rxe/rxe.c:243
 nldev_newlink+0x3a8/0x430 drivers/infiniband/core/nldev.c:1858
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0x439/0x570 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
 netlink_unicast+0x5a9/0x680 net/netlink/af_netlink.c:1364
 netlink_sendmsg+0x5be/0x6f0 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x532/0x580 net/socket.c:2713
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2767
 __sys_sendmsg net/socket.c:2799 [inline]
 __do_sys_sendmsg net/socket.c:2804 [inline]
 __se_sys_sendmsg net/socket.c:2802 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2802
 x64_sys_call+0x22ab/0x2550 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90004c87a10 of 1 bytes by task 6430 on cpu 0:
 rwsem_down_write_slowpath+0x462/0xab0 kernel/locking/rwsem.c:1207
 __down_write_common kernel/locking/rwsem.c:1347 [inline]
 __down_write kernel/locking/rwsem.c:1356 [inline]
 down_write+0xad/0xc0 kernel/locking/rwsem.c:1632
 kernfs_remove_by_name_ns+0x6b/0x110 fs/kernfs/dir.c:1792
 kernfs_remove_by_name include/linux/kernfs.h:644 [inline]
 remove_files fs/sysfs/group.c:28 [inline]
 sysfs_remove_group+0xa5/0x170 fs/sysfs/group.c:328
 sysfs_remove_groups+0x3a/0x80 fs/sysfs/group.c:352
 device_remove_groups drivers/base/core.c:2918 [inline]
 device_remove_attrs+0x15a/0x1a0 drivers/base/core.c:3054
 device_del+0x357/0x790 drivers/base/core.c:3964
 netdev_unregister_kobject+0x239/0x250 net/core/net-sysfs.c:2308
 unregister_netdevice_many_notify+0x1195/0x1560 net/core/dev.c:12562
 unregister_netdevice_many net/core/dev.c:12600 [inline]
 unregister_netdevice_queue+0x1cd/0x200 net/core/dev.c:12401
 unregister_netdevice include/linux/netdevice.h:3487 [inline]
 __tun_detach+0x9e4/0xc90 drivers/net/tun.c:637
 tun_detach drivers/net/tun.c:653 [inline]
 tun_chr_close+0x5a/0x100 drivers/net/tun.c:3587
 __fput+0x29e/0x630 fs/file_table.c:512
 ____fput+0x1c/0x30 fs/file_table.c:540
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1e4/0x8c0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
 do_syscall_64+0x212/0x360 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6430 Comm: syz.6.736 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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