Linux Kernel Memory Leak Vulnerability in ELF Binary Loader

A memory leak vulnerability has been identified in the Linux kernel's ELF binary loader function, load_elf_binary(). This issue occurs when the interpreter ELF execution structure fails to allocate memory, leading the program to an error handling path that does not properly release the 'interpreter' file resource. As a result, unreferenced file objects remain in memory, causing a leak. The vulnerability has been addressed by modifying the error handling to ensure that file resources are correctly released, preventing the memory leak.

Impact

Exploitation of this vulnerability leads to a memory leak, where unreferenced objects are not properly released, potentially causing increased memory usage and degradation of system performance over time.

Reproduction

The vulnerability can be reproduced by executing a program that is managed by the ELF binary loader in the Linux kernel. When the loader attempts to process the ELF binary, it may encounter a failure in allocating memory for the interpreter execution structure. This failure triggers the original error handling path that does not release the 'interpreter' file resource, creating a memory leak. Monitoring tools like kmemleak can be used to detect the unreferenced objects left in memory, confirming the presence of the leak.

Remediation

Users can upgrade to the latest version of the Linux kernel where this vulnerability has been fixed. Instructions for downloading the patched version are available on the official Linux kernel website.