{"id":"CVE-2026-53062","revision":"0f9ae608aa994ac6b609528f23c69e6c","records":[{"revision":"0f9ae608aa994ac6b609528f23c69e6c","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-53062","aliases":[],"title":"dm cache policy smq: fix missing locks in invalidating cache blocks","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm cache policy smq: fix missing locks in invalidating cache blocks\n\nIn passthrough mode, the policy invalidate_mapping operation is called\nsimultaneously from multiple workers, thus it should be protected by a\nlock. Otherwise, we might end up with data races on the allocated blocks\ncounter, or even use-after-free issues with internal data structures\nwhen doing concurrent writes.\n\nNote that the existing FIXME in smq_invalidate_mapping() doesn't affect\npassthrough mode since migration tasks don't exist there, but would need\nattention if supporting fast device shrinking via suspend/resume without\ntarget reloading.\n\nReproduce steps:\n\n1. Create a cache device consisting of 1024 cache entries\n\ndmsetup create cmeta --table \"0 8192 linear /dev/sdc 0\"\ndmsetup create cdata --table \"0 131072 linear /dev/sdc 8192\"\ndmsetup create corig --table \"0 262144 linear /dev/sdc 262144\"\ndd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct\ndmsetup create cache --table \"0 262144 cache /dev/mapper/cmeta \\\n/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0\"\n\n2. Populate the cache, and record the number of cached blocks\n\nfio --name=populate --filename=/dev/mapper/cache --rw=randwrite --bs=4k \\\n--size=64m --direct=1\nnr_cached=$(dmsetup status cache | awk '{split($7, a, \"/\"); print a[1]}')\n\n3. Reload the cache into passthrough mode\n\ndmsetup suspend cache\ndmsetup reload cache --table \"0 262144 cache /dev/mapper/cmeta \\\n/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 passthrough smq 0\"\ndmsetup resume cache\n\n4. Write to the passthrough cache. By setting multiple jobs with I/O\n   size equal to the cache block size, cache blocks are invalidated\n   concurrently from different workers.\n\nfio --filename=/dev/mapper/cache --name=test --rw=randwrite --bs=64k \\\n--direct=1 --numjobs=2 --randrepeat=0 --size=64m\n\n5. Check if demoted matches cached block count. These numbers should\n   match but may differ due to the data race.\n\nnr_demoted=$(dmsetup status cache | awk '{print $12}')\necho \"$nr_cached, $nr_demoted\"","state":0,"publishedAt":"2026-06-24T16:30:06.189+00:00","modifiedAt":"2026-10-19T19:47:14.719+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/md/dm-cache-policy-smq.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"4991b5a08751e2e82488fb93ae08849b6aea10d9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"1b2bec4a7dcf5f00b7a1cbeeec8997841d783513\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"9a5fdfb9e57ec3a8ad2b8fce5e5ffa42d53b130e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"ac5ee99443891bdb161f5539606a66a1b5e72542\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"93627a29d4b66d4a2def938dfb8610cc80ae454b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"c348ae47d8e65f06429fa41adce9ad986b696766\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"2b62d0611c9af14a16bddf22df2612b4f40eb5a1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b29d4986d0da1a27cd35917cdb433672f5c95d7f\",\n                            \"lessThan\": \"2d1f7b65f5deedd2e6b09fdc6ea27f8375f24b45\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/md/dm-cache-policy-smq.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.12\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.12\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.258\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.209\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.175\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.141\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.91\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.33\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.10\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/4991b5a08751e2e82488fb93ae08849b6aea10d9","https://git.kernel.org/stable/c/1b2bec4a7dcf5f00b7a1cbeeec8997841d783513","https://git.kernel.org/stable/c/9a5fdfb9e57ec3a8ad2b8fce5e5ffa42d53b130e","https://git.kernel.org/stable/c/ac5ee99443891bdb161f5539606a66a1b5e72542","https://git.kernel.org/stable/c/93627a29d4b66d4a2def938dfb8610cc80ae454b","https://git.kernel.org/stable/c/c348ae47d8e65f06429fa41adce9ad986b696766","https://git.kernel.org/stable/c/2b62d0611c9af14a16bddf22df2612b4f40eb5a1","https://git.kernel.org/stable/c/2d1f7b65f5deedd2e6b09fdc6ea27f8375f24b45"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53062","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-53062","identifiers":["CVE-2026-53062"]},"retained":false,"historicalAffected":[]}],"coverage":[]}