### [CVE-2025-38473](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-38473)
![](https://img.shields.io/static/v1?label=Product&message=Linux&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=&color=brightgreen)
![](https://img.shields.io/static/v1?label=Version&message=3.13%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Version&message=d97c899bde330cd1c76c3a162558177563a74362%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=blue)

### Description

In the Linux kernel, the following vulnerability has been resolved:Bluetooth: Fix null-ptr-deref in l2cap_sock_resume_cb()syzbot reported null-ptr-deref in l2cap_sock_resume_cb(). [0]l2cap_sock_resume_cb() has a similar problem that was fixed by commit1bff51ea59a9 ("Bluetooth: fix use-after-free error in lock_sock_nested()").Since both l2cap_sock_kill() and l2cap_sock_resume_cb() are executedunder l2cap_sock_resume_cb(), we can avoid the issue simply by checkingif chan->data is NULL.Let's not access to the killed socket in l2cap_sock_resume_cb().[0]:BUG: KASAN: null-ptr-deref in instrument_atomic_write include/linux/instrumented.h:82 [inline]BUG: KASAN: null-ptr-deref in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]BUG: KASAN: null-ptr-deref in l2cap_sock_resume_cb+0xb4/0x17c net/bluetooth/l2cap_sock.c:1711Write of size 8 at addr 0000000000000570 by task kworker/u9:0/52CPU: 1 UID: 0 PID: 52 Comm: kworker/u9:0 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPTHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025Workqueue: hci0 hci_rx_workCall trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:501 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_report+0x58/0x84 mm/kasan/report.c:524 kasan_report+0xb0/0x110 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189 __kasan_check_write+0x20/0x30 mm/kasan/shadow.c:37 instrument_atomic_write include/linux/instrumented.h:82 [inline] clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] l2cap_sock_resume_cb+0xb4/0x17c net/bluetooth/l2cap_sock.c:1711 l2cap_security_cfm+0x524/0xea0 net/bluetooth/l2cap_core.c:7357 hci_auth_cfm include/net/bluetooth/hci_core.h:2092 [inline] hci_auth_complete_evt+0x2e8/0xa4c net/bluetooth/hci_event.c:3514 hci_event_func net/bluetooth/hci_event.c:7511 [inline] hci_event_packet+0x650/0xe9c net/bluetooth/hci_event.c:7565 hci_rx_work+0x320/0xb18 net/bluetooth/hci_core.c:4070 process_one_work+0x7e8/0x155c kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3402 kthread+0x5fc/0x75c kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/w4zu/Debian_security