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 commit
1bff51ea59a9 ("Bluetooth: fix use-after-free error in lock_sock_nested()").
Since both l2cap_sock_kill() and l2cap_sock_resume_cb() are executed
under l2cap_sock_resume_cb(), we can avoid the issue simply by checking
if 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:1711
Write of size 8 at addr 0000000000000570 by task kworker/u9:0/52
CPU: 1 UID: 0 PID: 52 Comm: kworker/u9:0 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: hci0 hci_rx_work
Call 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
Metrics
Affected Vendors & Products
References
History
Tue, 29 Jul 2025 12:30:00 +0000
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threat_severity
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cvssV3_1
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Tue, 29 Jul 2025 08:00:00 +0000
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Linux
Linux linux Kernel |
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Vendors & Products |
Linux
Linux linux Kernel |
Mon, 28 Jul 2025 11:30:00 +0000
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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 commit 1bff51ea59a9 ("Bluetooth: fix use-after-free error in lock_sock_nested()"). Since both l2cap_sock_kill() and l2cap_sock_resume_cb() are executed under l2cap_sock_resume_cb(), we can avoid the issue simply by checking if 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:1711 Write of size 8 at addr 0000000000000570 by task kworker/u9:0/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u9:0 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: hci0 hci_rx_work Call 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 | |
Title | Bluetooth: Fix null-ptr-deref in l2cap_sock_resume_cb() | |
References |
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Status: PUBLISHED
Assigner: Linux
Published: 2025-07-28T11:21:34.880Z
Updated: 2025-07-28T11:21:34.880Z
Reserved: 2025-04-16T04:51:24.021Z
Link: CVE-2025-38473

No data.

Status : Awaiting Analysis
Published: 2025-07-28T12:15:29.123
Modified: 2025-07-29T14:14:29.590
Link: CVE-2025-38473
