Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
net: airoha: Fix potential use-after-free in airoha_ppe_deinit()
airoha_ppe_deinit() replaces the NPU pointer with NULL via rcu_replace_pointer() but does not wait for existing RCU readers to exit before calling ppe_deinit() and airoha_npu_put(). This can cause a use-after-free if a reader in an RCU read-side critical section still holds a reference to the NPU when it is freed.
The init path (airoha_ppe_init) already calls synchronize_rcu() after rcu_assign_pointer(), but the deinit path introduced in commit 6abcf751bc08 (“net: airoha: Fix schedule while atomic in airoha_ppe_deinit()”) omitted the matching barrier when switching from rcu_read_lock()/rcu_dereference() to rcu_replace_pointer().
Add synchronize_rcu() before ppe_deinit() to ensure all existing RCU readers have completed before the NPU resources are released.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , RHEL 7 ELS , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 2.6.32 (+8 more)