Linux Kernel NULL Pointer Dereference Vulnerability in Microsoft Azure Network Adapter Driver

A NULL pointer dereference vulnerability has been identified in the Linux kernel's Microsoft Azure Network Adapter (MANA) driver. This issue arises when queue allocation fails, leading to the error cleanup process freeing and nullifying certain pointers. Subsequent teardown operations can then inadvertently dereference these nullified pointers, causing a panic. The vulnerability is present in the Linux kernel stable tree, specifically in versions prior to the latest commit that addresses this issue.

Impact

Exploitation of this vulnerability leads to a NULL pointer dereference, causing a kernel panic.

Reproduction

The vulnerability can be reproduced by allocating queues for a network adapter using the MANA driver and then simulating a failure during the allocation process. This will cause the driver to free and nullify the queue pointers. Following this, the teardown process can be initiated, which will attempt to dereference the null pointers without performing the necessary NULL checks, leading to a kernel panic.

Remediation

Users can upgrade to the latest version of the Linux kernel stable tree, where this vulnerability has been addressed.