{"id":"CVE-2026-98629","revision":"077ecafd111a4f6fba275086f9b177fd","records":[{"revision":"077ecafd111a4f6fba275086f9b177fd","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98629","aliases":[],"title":"net/sched: cls_u32: fix manual hash table handle IDR aliasing","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_u32: fix manual hash table handle IDR aliasing\n\nA u32 hash table created with an explicit handle ('tc filter add ...\nhandle 801: u32 divisor N') keys its IDR entry on the raw handle, while\nthe destroy paths free it under handle2id(handle). The two key domains\ndisagree for handles in the 0x800..0xFFF htid range:\nhandle2id() folds them back into the auto-allocated id space (1..0x7FF).\n\nA manual table therefore leaves its raw-keyed IDR entry unreachable on\ndelete (a permanent leak), and its delete can drop the idr entry of an\nunrelated live auto table. A later auto allocation can then hand out a\nhandle that aliases the live manual table; u32_lookup_ht() first-match\nroutes lookups and TCA_U32_LINK for that htid to the wrong table.\n\nKey the divisor-path alloc on handle2id(handle) so allocation and\nremoval share one key domain. A manual handle that maps onto an id\nalready in use is rejected with -ENOSPC, and auto allocation skips ids\nheld by live manual tables.\n\nConditions to recreate:\n ip link add test0 type dummy\n tc qdisc add dev test0 clsact\n tc filter add dev test0 ingress protocol ip pref 1 \\\n handle 801: u32 divisor 16\n tc filter add dev test0 ingress protocol ip pref 2 u32 divisor 16\n tc -d filter show dev test0 ingress | grep 'fh 801:'\n # unpatched: two live tables with handle 0x80100000 (the pref 2 root\n # hnode is auto-allocated id 1); patched: the auto hnode takes id 2.\n\nAlso tested with a poc with a live u32 table on the block, add/delete a manual\ntable 'handle 901: u32 divisor 1' twice; unpatched, the re-add fails with\n-ENOSPC because the raw key leaked on the first delete.","state":0,"publishedAt":"2026-10-18T15:19:50.589+00:00","modifiedAt":"2026-10-19T09:22:57.219+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 \"net/sched/cls_u32.c\"\n ],\n \"versions\": [\n {\n \"version\": \"9b2c3184e126b941dfa716b8128ed6db92a64e2f\",\n \"lessThan\": \"21fc07924e996e1e661268ca269c86b8d59d25b3\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"789f9963bd031c3a185605665b744912df8e7eda\",\n \"lessThan\": \"0fac292d93fdb313099e98cce928b3a524c92c94\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"73af53d82076bbe184d9ece9e14b0dc8599e6055\",\n \"lessThan\": \"54a454c5e41f5e2cb70c8163140ce095c5d5eefd\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"73af53d82076bbe184d9ece9e14b0dc8599e6055\",\n \"lessThan\": \"f6696481eedfd5752b4b56eed715d0b0fe48b9c5\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"73af53d82076bbe184d9ece9e14b0dc8599e6055\",\n \"lessThan\": \"2f898f9ec7c73c5697ee462681e7ea6984ee1f3d\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"73af53d82076bbe184d9ece9e14b0dc8599e6055\",\n \"lessThan\": \"0a5f5d9e94dead312d32c366b917c64e552b72f7\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"4403f9293ce9ecc2a55c688d84ee37e3ba0fc1a8\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"6.1.119\",\n \"lessThan\": \"6.1.189\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.63\",\n \"lessThan\": \"6.6.158\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.11.10\",\n \"lessThan\": \"6.12\",\n \"status\": \"affected\",\n \"versionType\": \"semver\"\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 \"net/sched/cls_u32.c\"\n ],\n \"versions\": [\n {\n \"version\": \"6.12\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"6.12\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.189\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.158\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.112\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.55\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.2.9\",\n \"lessThanOrEqual\": \"7.2.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.3\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/21fc07924e996e1e661268ca269c86b8d59d25b3","https://git.kernel.org/stable/c/0fac292d93fdb313099e98cce928b3a524c92c94","https://git.kernel.org/stable/c/54a454c5e41f5e2cb70c8163140ce095c5d5eefd","https://git.kernel.org/stable/c/f6696481eedfd5752b4b56eed715d0b0fe48b9c5","https://git.kernel.org/stable/c/2f898f9ec7c73c5697ee462681e7ea6984ee1f3d","https://git.kernel.org/stable/c/0a5f5d9e94dead312d32c366b917c64e552b72f7"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98629","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98629","identifiers":["CVE-2026-98629"]},"retained":false,"historicalAffected":[]}],"coverage":[]}