Linux Kernel Rxrpc Deadlock Vulnerability in AFS Module

A deadlock vulnerability has been identified in the Linux kernel within the AFS (Andrew File System) module, specifically in versions through 6.13.0-rc5. The issue arises because the AFS address list retains references to rxrpc_peer objects, which are freed under RCU (Read-Copy-Update) management. When an rxrpc_peer object is dereferenced and removed from the peer hash table, it requires a spinlock. However, this operation can conflict with the RCU cleanup process, leading to a potential deadlock scenario. The vulnerability has been acknowledged and addressed by modifying the locking mechanism to prevent such conflicts.

Impact

Exploitation of this vulnerability can lead to a deadlock situation, where the system becomes unresponsive due to conflicting lock management between the AFS module and the RCU cleanup process.