{"id":"CVE-2026-80960","summary":"dm-pcache: validate on-media seg_num against the cache device size","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm-pcache: validate on-media seg_num against the cache device size\n\nseg_num is read from the crc32c-only superblock, so whoever supplies the\ncache device on a table load (CAP_SYS_ADMIN) controls it. It sizes\ncache-\u003esegments[] and is the value every later on-media segment id is\nbounded against, yet it is never checked against the device. Because\ncache_dev-\u003emapping is the direct map of the pmem, CACHE_DEV_SEGMENT() for\na segment id past the device resolves to ordinary kernel memory beyond\nthe mapping; a new-cache init reaching such an id has cache_seg_init() -\u003e\ncache_dev_zero_range() memset() 12 KiB over that memory -- an\nout-of-bounds write into the kernel heap at table load. A zero seg_num\nmakes the segment allocations ZERO_SIZE_PTR.\n\nReject a seg_num that is zero, larger than the device can hold, or larger\nthan PCACHE_CACHE_SEGS_MAX before it is used.","modified":"2026-09-13T03:47:04.515263517Z","published":"2026-09-11T19:42:27.182Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80960.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/62d92e45abe9e087370f9fc5d876b95673aced34"},{"type":"WEB","url":"https://git.kernel.org/stable/c/91b93fe5cf4d62d5ecc642a6c8f15a3c11b00e3c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e889c0ee81165fc90aad2979b51f930f77895703"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80960.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80960"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1d57628ff95b32d5cfa8d8f50e07690c161e9cf0"},{"fixed":"91b93fe5cf4d62d5ecc642a6c8f15a3c11b00e3c"},{"fixed":"e889c0ee81165fc90aad2979b51f930f77895703"},{"fixed":"62d92e45abe9e087370f9fc5d876b95673aced34"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80960.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.18.0"},{"fixed":"6.18.50"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80960.json"}}],"schema_version":"1.9.0"}