Medium · published February 27, 2025
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: handle NULL sock pointer in l2cap_sock_alloc
A NULL sock pointer is passed into l2cap_sock_alloc() when it is called
from l2cap_sock_new_connection_cb() and the error handling paths should
also be aware of it.
Seemingly a more elegant solution would be to swap bt_sock_alloc() and
l2cap_chan_create() calls since they are not interdependent to that moment
but then l2cap_chan_create() adds the soon to be deallocated and still
dummy-initialized channel to the global list accessible by many L2CAP
paths. The channel would be removed from the list in short period of time
but be a bit more straight-forward here and just check for NULL instead of
changing the order of function calls.
Found by Linux Verification Center (linuxtesting.org) with SVACE static
analysis tool.
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 5.4.287, < 5.4.291 | 5.4.291 |
| linux/linux_kernel | ≥ 5.10.231, < 5.10.235 | 5.10.235 |
| linux/linux_kernel | ≥ 5.15.174, < 5.15.179 | 5.15.179 |
| linux/linux_kernel | ≥ 6.1.120, < 6.1.129 | 6.1.129 |
| linux/linux_kernel | ≥ 6.6.66, < 6.6.78 | 6.6.78 |
| linux/linux_kernel | ≥ 6.12.5, < 6.12.14 | 6.12.14 |
| linux/linux_kernel | ≥ 6.13, < 6.13.3 | 6.13.3 |