Linux Kernel QAT RSA Memory Leak Vulnerability

A memory leak vulnerability has been identified in the Linux kernel's crypto component, specifically within the QuickAssist Technology (QAT) RSA implementation. When an RSA key is used in form 2, as defined by PKCS #1 V2.1, certain parts of the private key remain in memory even after the transformation (TFM) is released. This issue arises because the explicit calls to free the buffers in the 'qat_rsa_exit_tfm()' function do not adequately clear all referenced buffers in the TFM context. The vulnerability has been addressed by replacing these explicit free calls with a single call to 'qat_rsa_clear_ctx()', which properly frees all associated buffers.

Impact

Exploitation of this vulnerability leads to a memory leak, where sensitive data such as private RSA key components are not properly cleared from memory, potentially allowing for unauthorized access to this information.