KCSAN: data-race in kobject_put / kobject_uevent

Title	Replies (including bot)	Last reply
[syzbot] [kernel?] KCSAN: data-race in kobject_put / kobject_uevent_env (2)	3 (4)	2024/07/18 13:34

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in kobject_put / kobject_uevent_env kernel				1	129d	129d	0/27	auto-obsoleted due to no activity on 2024/06/05 16:52

llcp: llcp_sock_recvmsg: Recv datagram failed state 3 -6 0
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BUG: KCSAN: data-race in kobject_put / kobject_uevent_env

read-write to 0xffff888139ddec54 of 1 bytes by task 22621 on cpu 0:
 kobject_uevent_env+0x4e/0x550 lib/kobject_uevent.c:476
 kobject_uevent+0x1c/0x30 lib/kobject_uevent.c:641
 device_del+0x6fa/0x780 drivers/base/core.c:3886
 nfc_unregister_device+0x114/0x130 net/nfc/core.c:1183
 nci_unregister_device+0x14c/0x160 net/nfc/nci/core.c:1312
 virtual_ncidev_close+0x30/0x50 drivers/nfc/virtual_ncidev.c:172
 __fput+0x192/0x6f0 fs/file_table.c:422
 ____fput+0x15/0x20 fs/file_table.c:450
 task_work_run+0x13a/0x1a0 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888139ddec54 of 1 bytes by task 22615 on cpu 1:
 kobject_put+0x25/0x180 lib/kobject.c:733
 put_device+0x1f/0x30 drivers/base/core.c:3787
 nfc_put_device net/nfc/nfc.h:103 [inline]
 nfc_llcp_local_put+0x87/0xb0 net/nfc/llcp_core.c:196
 nfc_llcp_sock_free net/nfc/llcp_sock.c:1021 [inline]
 llcp_sock_destruct+0x14d/0x1a0 net/nfc/llcp_sock.c:966
 __sk_destruct+0x3d/0x440 net/core/sock.c:2175
 sk_destruct net/core/sock.c:2223 [inline]
 __sk_free+0x284/0x2d0 net/core/sock.c:2234
 sk_free+0x39/0x70 net/core/sock.c:2245
 sock_put include/net/sock.h:1879 [inline]
 llcp_sock_release+0x38f/0x3d0 net/nfc/llcp_sock.c:646
 __sock_release net/socket.c:659 [inline]
 sock_close+0x68/0x150 net/socket.c:1421
 __fput+0x192/0x6f0 fs/file_table.c:422
 ____fput+0x15/0x20 fs/file_table.c:450
 task_work_run+0x13a/0x1a0 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xbe/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x07 -> 0x0d

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22615 Comm: syz.0.6322 Tainted: G        W          6.10.0-syzkaller-01155-gd67978318827 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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