In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen() l2cap_chan_close() removes the channel from conn->chan_l, which must be done under conn->lock. cleanup_listen() runs under the parent sk_lock, so acquiring conn->lock would invert the established conn->lock -> chan->lock -> sk_lock order. Instead of calling l2cap_chan_close() directly, schedule l2cap_chan_timeout with delay 0 to close the channel asynchronously. The timeout handler already acquires conn->lock and chan->lock in the correct order. The timer is only armed when chan->conn is still set: if it is already NULL, l2cap_conn_del() has already processed this channel (l2cap_chan_del + l2cap_sock_teardown_cb + l2cap_sock_close_cb), so there is nothing left to do. If l2cap_conn_del() races in after the timer is armed, __clear_chan_timer() inside l2cap_chan_del() cancels it; if the timer has already fired, the handler returns harmlessly because chan->conn was cleared.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | ADJACENT_NETWORK |
|---|---|
| Attack Complexity | LOW |
| Privileges Required | NONE |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | HIGH |
| Integrity Impact | HIGH |
| Availability Impact | HIGH |
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Type: Secondary
Exploitability Score: 2.8
Impact Score: 5.9
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
CWE-667
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384ab49c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384ab6140> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd2d39fd440> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd319c765c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384ab5880> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384ab5c40> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd2d39fd200> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd319c760c0> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd2d39fd740> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd384ab5bc0> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd2a2df8ac0> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd2a2dfab00> | Operating System |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* |