The vulnerability involves the Linux kernel's handling of BPF inode storage maps (BPF_MAP_TYPE_INODE_STORAGE) when the BPF LSM (Linux Security Module) is compiled in but not explicitly enabled at boot. Without BPF LSM initialization, a critical offset used in inode security is left at a default incorrect value, causing the kernel to overwrite a function pointer in the inode's RCU callback structure with NULL. This leads to a kernel panic when the RCU callback is later executed. The fix introduces a global flag indicating BPF LSM initialization status and prevents creation of inode storage maps if the BPF LSM is uninitialized, thereby avoiding the faulty state.

A privileged user can trigger a kernel panic by creating and updating a BPF_MAP_TYPE_INODE_STORAGE map when the BPF LSM is uninitialized. This results in a NULL pointer dereference during inode destruction, causing a denial of service via system crash. There is no indication of code execution or privilege escalation beyond causing a kernel panic.

A fix has been implemented in the Linux kernel that introduces a global flag to track BPF LSM initialization and prevents allocation of BPF inode storage maps if the BPF LSM is uninitialized. Users should apply the official kernel updates that include this fix. Patch status is not explicitly stated in the provided data; therefore, check the vendor advisory for current remediation guidance.