Executive brief
A memory leak vulnerability was identified in the Linux kernel's HFS+ filesystem driver, which is used to read and write Apple-formatted disks. If a specific error occurs while mounting a disk, the system fails to release certain memory resources. Over time, repeated triggers of this flaw could lead to system instability or a denial-of-service by exhausting available system memory.
Technical details
A memory leak exists in the hfsplus filesystem driver due to an incorrect allocation pattern introduced during its conversion to the new mount API. Specifically, if setup_bdev_super() fails after a new superblock has been allocated by sget_fc() but before hfsplus_fill_super() takes ownership of the s_fs_info data, the memory is never freed. This vulnerability can be triggered by a local user with permissions to mount HFS+ filesystems. The fix involves ensuring sb->s_fs_info is explicitly freed in hfsplus_kill_super(). Patches have been released for various stable kernel branches including 6.18.16 and 6.19.6.
Affected products
- Linux Linux Kernel 6.13 to 6.18.16, 6.19 to 6.19.6
Timeline
- 2025-12-01: other: Patch authored
- 2026-05-06: disclosed: CVE published
- 2026-05-06: advisory