Linux Kernel Use-After-Free Vulnerability in mshv_map_user_memory Error Path

A use-after-free vulnerability has been identified in the Linux kernel's Hyper-V management service (mshv) component. This issue arises in the error handling path of the mshv_map_user_memory() function. When an error occurs, the function directly frees a memory region using vfree(), but this leaves the MMU notifier still registered. Later, when userspace unmaps the memory, the notifier accesses the freed region, leading to a use-after-free condition and a potential kernel panic. The vulnerability affects the Linux kernel stable tree.

Impact

Exploitation of this vulnerability causes a use-after-free condition, which can lead to a kernel panic.

Remediation

The vulnerability has been fixed in the Linux kernel. Users can upgrade to the latest version to address this issue.