dm-pcache: only hand out initialized cache segments
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.18.50, 7.2.4
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: dm-pcache: only hand out initialized cache segments get_cache_segment() scans the segment map up to cache->n_segs, the physical device segment count, but cache_segs_init() only initializes the first cache_info->n_segs segments. A crafted image with cache_info->n_segs smaller than the device count leaves the remaining pcache_cache_segment structs zeroed (segment.data == NULL), and the allocator can hand one to cache_kset_close(), which writes through the returned segment's data pointer with no NULL check. Bound the allocator's search to cache_info->n_segs so only initialized segments are ever returned. A conforming cache sets n_segs equal to the device segment count, so this rejects nothing legitimate.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 · fixed in 83e3116283ed2c6a6a1fa662862a4b4d7d2701a2; From 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 · fixed in 692037ae1a7cfacc2f0c22c6e034c1dfee0e553f; From 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 · fixed in 2df0fc042e299bae3c0f60ea5cd2af9285658e9f
- Linux Linux
6.18
- KernelLinux
From 6.18.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4