Linux Kernel LSM General Protection Fault Vulnerability in Legacy Parse Param Handling

A vulnerability in the Linux kernel's handling of legacy mount options can lead to a general protection fault. This issue arises within the Linux Security Module (LSM) framework, where the 'bail on fail' scheme fails to address scenarios where a security module returns an error code indicating unrecognized input. In this case, the Smack security module correctly acknowledges a mount option and returns 0, but subsequent BPF hook calls return -ENOPARAM, creating confusion. Additionally, the SELinux hook improperly indicates success by returning 1 instead of the expected 0, contributing to the issue.

Impact

Exploitation of this vulnerability causes a general protection fault, which can lead to a denial of service by crashing the system or causing instability.