Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas_tf: fix use-after-free in lbtf_free_adapter()
lbtf_free_adapter() calls timer_delete(&priv->command_timer), which does not wait for a running command_timer_fn() callback. lbtf_free_adapter() runs on the teardown path right before ieee80211_free_hw() frees priv, both in lbtf_remove_card() and in the probe error path. command_timer is armed by mod_timer() in lbtf_cmd() whenever a firmware command is sent. command_timer_fn() dereferences priv. If a command times out as the device is removed, command_timer_fn() runs concurrently with teardown and dereferences priv after it has been freed.
This is the same use-after-free that commit 03cc8f90d053 (“wifi: libertas: fix use-after-free in lbs_free_adapter()”) fixed in the sibling libertas driver. The libertas_tf variant has the identical pattern and was left unchanged. Use timer_delete_sync() so any in-flight callback completes before priv is freed.
Details
- Affected product:
- Debian 10 ELS , Debian 11 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.4.0 (+4 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Planned | — |
| Oracle Linux 9 UEK 7 | Planned | — |