Linux Kernel NTFS3 Memory Leak Vulnerability

A memory leak vulnerability has been identified in the Linux kernel's NTFS3 file system handling. The issue arises in the 'ntfs_read_mft' function, where the 'ATTR_ROOT' label incorrectly sets the 'is_root' flag to true without also setting the 'NI_FLAG_DIR' flag. This inconsistency can lead to a memory leak, as the allocated memory for directory attributes is not properly freed. The problem was reported by the kernel's memory leak detector, 'kmemleak'.

Impact

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

Reproduction

The vulnerability can be reproduced by mounting an NTFS file system with a directory that has attributes triggering the 'ATTR_ROOT' label in the 'ntfs_read_mft' function. The 'is_root' flag will be set, but without the corresponding 'NI_FLAG_DIR' flag, creating the conditions for the memory leak. After the file system is unmounted, the 'kmemleak' tool will report the leaked memory as an unreferenced object, indicating that the allocated memory was not properly freed.

Remediation

Users can upgrade to the latest version of the Linux kernel where this vulnerability has been fixed. Instructions for upgrading the Linux kernel can be found in the official Linux kernel documentation.