Vulnerability feed

Executive summary

This advisory describes a fix in the Linux kernel's dm-integrity device-mapper driver, where the superblock could be altered on disk while the device was suspended and the driver would then resume using values that no longer matched its in-memory structures. The advisory does not state a severity rating or exploitation status. The fix makes the driver refuse to resume if the geometry-defining superblock fields changed, and the advisory points to a kernel stable tree commit as the remedy.

Technical summary

The flaw is an input validation issue (inconsistent state after superblock modification) in dm-integrity's resume path, which re-reads the superblock without validating it. According to the commit message, an increased log2_sectors_per_block can push a journal index past the end of the journal and cause a 512-byte write through lowmem_page_address(NULL). The precondition is that the superblock on the underlying device is modified while the dm-integrity device is suspended. The fix snapshots the validated superblock in the constructor and rejects resume when geometry fields change. The advisory does not state affected or fixed version numbers, a CVSS score, workarounds, or detection guidance beyond the commit diff.

Summaries are generated by AI from the linked advisory text. Confirm versions and fixes at the source.

Summarized from git.kernel.org/stable/c/454b67fcc28c185…dfb9f067b04c28628ada

Score

No CVSS score published.

Affects

LinuxLinuxLinux kernelLinux dm-integrity