{"id":"CVE-2026-90073","revision":"8a4e25eadcf34ec1a216b9547d0bb073","records":[{"revision":"8a4e25eadcf34ec1a216b9547d0bb073","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90073","aliases":[],"title":"net/sched: hhf: clamp quantum before hhf_change() to avoid overflow","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: hhf: clamp quantum before hhf_change() to avoid overflow\n\nhhf_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) with no overflow\ncheck. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting\nMTU 2147483634) makes weight * quantum overflow the signed deficit in\nhhf_dequeue(), spinning forever.\n\nClamp q->quantum before hhf_change() so both the opt and !opt paths see\na sane quantum. Without this, bare \"tc qdisc add ... hhf\" succeeds with\na clamped quantum but \"tc qdisc add ... hhf limit 1000\" (any option\npresent) fails with -EINVAL because hhf_change() re-validates the\nunclamped default (sch_hhf.c:559). 256 matches fq_codel's floor and is\na sane minimum for a DRR quantum.\n\nConditions to recreate the bug: a device whose MTU (plus\nhard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy\ndevice with max_mtu == 0 accepting MTU 2147483634). Requires\nCAP_NET_ADMIN in a user namespace.","state":0,"publishedAt":"2026-09-17T16:05:53.562+00:00","modifiedAt":"2026-10-19T08:57:30.227+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/sch_hhf.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"2e0f0729f922c8de13801004e2131b57646c7c5f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"0c66223e90ddb4fd3700965a9241f2fde7bd6bc7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"20b65bf7ca06e48ec1d62ed8012f71205328dbe4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"dea2789a9d5ff38bdd77f2e64d550430899e2839\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"fa9c2055f0a60f801ccf286af53d387dc6202c3f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"99770b5d8e0e1c69b996f74a19d71afd2c4a9aa4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"2446644b0f6d045b01db6acbaf55552dbec8a59a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"10239edf86f137ce4c39b62ea9575e8053c549a0\",\n                            \"lessThan\": \"2164b512b97bb053e8ce4d6e95576f11bed6a005\",\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                        \"net/sched/sch_hhf.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.14\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.14\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.270\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.221\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.188\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.157\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.110\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.52\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\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/2e0f0729f922c8de13801004e2131b57646c7c5f","https://git.kernel.org/stable/c/0c66223e90ddb4fd3700965a9241f2fde7bd6bc7","https://git.kernel.org/stable/c/20b65bf7ca06e48ec1d62ed8012f71205328dbe4","https://git.kernel.org/stable/c/dea2789a9d5ff38bdd77f2e64d550430899e2839","https://git.kernel.org/stable/c/fa9c2055f0a60f801ccf286af53d387dc6202c3f","https://git.kernel.org/stable/c/99770b5d8e0e1c69b996f74a19d71afd2c4a9aa4","https://git.kernel.org/stable/c/2446644b0f6d045b01db6acbaf55552dbec8a59a","https://git.kernel.org/stable/c/2164b512b97bb053e8ce4d6e95576f11bed6a005"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90073","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90073","identifiers":["CVE-2026-90073"]},"retained":false,"historicalAffected":[]}],"coverage":[]}