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BUG: KCSAN: data-race in rwsem_down_write_slowpath / rwsem_down_write_slowpath

write to 0xffffc9000127fb58 of 1 bytes by task 6338 on cpu 1:
 rwsem_try_write_lock kernel/locking/rwsem.c:653 [inline]
 rwsem_down_write_slowpath+0x3c9/0xa90 kernel/locking/rwsem.c:1159
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1591
 kernfs_remove_by_name_ns+0x5c/0xf0 fs/kernfs/dir.c:1717
 kernfs_remove_by_name include/linux/kernfs.h:633 [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
 destroy_gid_attrs drivers/infiniband/core/sysfs.c:1138 [inline]
 ib_free_port_attrs+0x8e/0x260 drivers/infiniband/core/sysfs.c:1362
 remove_one_compat_dev drivers/infiniband/core/device.c:1010 [inline]
 rdma_dev_exit_net+0x1aa/0x290 drivers/infiniband/core/device.c:1148
 ops_exit_list net/core/net_namespace.c:199 [inline]
 ops_undo_list+0x285/0x420 net/core/net_namespace.c:252
 setup_net+0x1f2/0x230 net/core/net_namespace.c:462
 copy_net_ns+0x310/0x450 net/core/net_namespace.c:581
 create_new_namespaces+0x20e/0x440 kernel/nsproxy.c:130
 unshare_nsproxy_namespaces+0xe6/0x120 kernel/nsproxy.c:226
 ksys_unshare+0x3f2/0x6f0 kernel/fork.c:3174
 __do_sys_unshare kernel/fork.c:3245 [inline]
 __se_sys_unshare kernel/fork.c:3243 [inline]
 __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3243
 x64_sys_call+0x1cef/0x3020 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc9000127fb58 of 1 bytes by task 6408 on cpu 0:
 rwsem_down_write_slowpath+0x43d/0xa90 kernel/locking/rwsem.c:1177
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0xab/0xc0 kernel/locking/rwsem.c:1591
 kernfs_remove_by_name_ns+0x5c/0xf0 fs/kernfs/dir.c:1717
 kernfs_remove_by_name include/linux/kernfs.h:633 [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
 destroy_port drivers/infiniband/core/sysfs.c:1233 [inline]
 ib_free_port_attrs+0x173/0x260 drivers/infiniband/core/sysfs.c:1363
 remove_one_compat_dev drivers/infiniband/core/device.c:1010 [inline]
 rdma_dev_exit_net+0x1aa/0x290 drivers/infiniband/core/device.c:1148
 ops_exit_list net/core/net_namespace.c:199 [inline]
 ops_undo_list+0x285/0x420 net/core/net_namespace.c:252
 setup_net+0x1f2/0x230 net/core/net_namespace.c:462
 copy_net_ns+0x310/0x450 net/core/net_namespace.c:581
 create_new_namespaces+0x20e/0x440 kernel/nsproxy.c:130
 unshare_nsproxy_namespaces+0xe6/0x120 kernel/nsproxy.c:226
 ksys_unshare+0x3f2/0x6f0 kernel/fork.c:3174
 __do_sys_unshare kernel/fork.c:3245 [inline]
 __se_sys_unshare kernel/fork.c:3243 [inline]
 __x64_sys_unshare+0x1f/0x30 kernel/fork.c:3243
 x64_sys_call+0x1cef/0x3020 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6408 Comm: syz.4.839 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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