{"id":"CVE-2026-98010","state":"PUBLISHED","title":"net/sched: drr: clamp quantum in change class","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: drr: clamp quantum in change class\n\ndrr_change_class() rejects explicit quantum==0 but falls back to\npsched_mtu() with no floor. With a crafted size table qdisc_pkt_len\nreaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless\ndevice) makes the deficit-refill loop spin under the qdisc lock.\n\nAdd clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the\nfallback path. The explicit-zero reject is preserved.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root drr\n  tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1","publishedAt":"2026-09-25T10:23:34.738Z","updatedAt":"2026-10-19T09:12:15.743Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"e2297bbf9cf6ece86f1d1f8c683517a994990f9e","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"560794ee6e040b6e1c4ac2b3c8909f341a4596ee","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"23fea7e6736b2e1c6f6f2f05cccf33d36834da73","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"b464affe9f9dfe41ac48930c376e3fb8596651b0","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"dc8b374214ef5bba4882bbd95b361e42555cfc0d","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"d43cded350fe1218493ad3d37a276aff14108ae6","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"8382abec0f1568d0a5590d75a3df92f23fcf5196","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_drr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.29","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.29","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_drr.c"]}],"references":["https://git.kernel.org/stable/c/e2297bbf9cf6ece86f1d1f8c683517a994990f9e","https://git.kernel.org/stable/c/560794ee6e040b6e1c4ac2b3c8909f341a4596ee","https://git.kernel.org/stable/c/23fea7e6736b2e1c6f6f2f05cccf33d36834da73","https://git.kernel.org/stable/c/b464affe9f9dfe41ac48930c376e3fb8596651b0","https://git.kernel.org/stable/c/dc8b374214ef5bba4882bbd95b361e42555cfc0d","https://git.kernel.org/stable/c/d43cded350fe1218493ad3d37a276aff14108ae6","https://git.kernel.org/stable/c/8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b","https://git.kernel.org/stable/c/8382abec0f1568d0a5590d75a3df92f23fcf5196"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98010.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98010","state":"PUBLISHED","datePublished":"2026-09-25T10:23:34.738Z","dateUpdated":"2026-10-19T09:12:15.743Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:19:56.068Z"},"containers":{"cna":{"title":"net/sched: drr: clamp quantum in change class","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: drr: clamp quantum in change class\n\ndrr_change_class() rejects explicit quantum==0 but falls back to\npsched_mtu() with no floor. With a crafted size table qdisc_pkt_len\nreaches ~2 GiB, so quantum=1 (or a zero psched_mtu on a headerless\ndevice) makes the deficit-refill loop spin under the qdisc lock.\n\nAdd clamp_t(u32, quantum, 256, 1<<20) after the zero reject and on the\nfallback path. The explicit-zero reject is preserved.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_DRR=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root drr\n  tc class add dev dummy0 parent 1: classid 1:1 drr quantum 1"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"e2297bbf9cf6ece86f1d1f8c683517a994990f9e","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"560794ee6e040b6e1c4ac2b3c8909f341a4596ee","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"23fea7e6736b2e1c6f6f2f05cccf33d36834da73","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"b464affe9f9dfe41ac48930c376e3fb8596651b0","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"dc8b374214ef5bba4882bbd95b361e42555cfc0d","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"d43cded350fe1218493ad3d37a276aff14108ae6","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b","versionType":"git"},{"version":"13d2a1d2b032de08d7dcab6a1edcd47802681f96","status":"affected","lessThan":"8382abec0f1568d0a5590d75a3df92f23fcf5196","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_drr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.29","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.29","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_drr.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/e2297bbf9cf6ece86f1d1f8c683517a994990f9e"},{"url":"https://git.kernel.org/stable/c/560794ee6e040b6e1c4ac2b3c8909f341a4596ee"},{"url":"https://git.kernel.org/stable/c/23fea7e6736b2e1c6f6f2f05cccf33d36834da73"},{"url":"https://git.kernel.org/stable/c/b464affe9f9dfe41ac48930c376e3fb8596651b0"},{"url":"https://git.kernel.org/stable/c/dc8b374214ef5bba4882bbd95b361e42555cfc0d"},{"url":"https://git.kernel.org/stable/c/d43cded350fe1218493ad3d37a276aff14108ae6"},{"url":"https://git.kernel.org/stable/c/8f756ae1c87414ce9cc21b30e6e4c036d6e9e80b"},{"url":"https://git.kernel.org/stable/c/8382abec0f1568d0a5590d75a3df92f23fcf5196"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:12:15.743Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"5.10.271"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"5.15.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.1.189"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.29","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}