{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-56751", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T11:26:39.759Z", "datePublished": "2024-12-29T11:30:16.805Z", "dateUpdated": "2026-05-11T20:58:23.094Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T20:58:23.094Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: release nexthop on device removal\n\nThe CI is hitting some aperiodic hangup at device removal time in the\npmtu.sh self-test:\n\nunregister_netdevice: waiting for veth_A-R1 to become free. Usage count = 6\nref_tracker: veth_A-R1@ffff888013df15d8 has 1/5 users at\n\tdst_init+0x84/0x4a0\n\tdst_alloc+0x97/0x150\n\tip6_dst_alloc+0x23/0x90\n\tip6_rt_pcpu_alloc+0x1e6/0x520\n\tip6_pol_route+0x56f/0x840\n\tfib6_rule_lookup+0x334/0x630\n\tip6_route_output_flags+0x259/0x480\n\tip6_dst_lookup_tail.constprop.0+0x5c2/0x940\n\tip6_dst_lookup_flow+0x88/0x190\n\tudp_tunnel6_dst_lookup+0x2a7/0x4c0\n\tvxlan_xmit_one+0xbde/0x4a50 [vxlan]\n\tvxlan_xmit+0x9ad/0xf20 [vxlan]\n\tdev_hard_start_xmit+0x10e/0x360\n\t__dev_queue_xmit+0xf95/0x18c0\n\tarp_solicit+0x4a2/0xe00\n\tneigh_probe+0xaa/0xf0\n\nWhile the first suspect is the dst_cache, explicitly tracking the dst\nowing the last device reference via probes proved such dst is held by\nthe nexthop in the originating fib6_info.\n\nSimilar to commit f5b51fe804ec (\"ipv6: route: purge exception on\nremoval\"), we need to explicitly release the originating fib info when\ndisconnecting a to-be-removed device from a live ipv6 dst: move the\nfib6_info cleanup into ip6_dst_ifdown().\n\nTested running:\n\n./pmtu.sh cleanup_ipv6_exception\n\nin a tight loop for more than 400 iterations with no spat, running an\nunpatched kernel I observed a splat every ~10 iterations." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/route.c" ], "versions": [ { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "77aa9855a878fb43f547ddfbda3127a1e88ad31a", "status": "affected", "versionType": "git" }, { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "b2f26a27ea3f72f75d18330f76f5d1007c791848", "status": "affected", "versionType": "git" }, { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "43e25adc80269f917d2a195f0d59f74cdd182955", "status": "affected", "versionType": "git" }, { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "a3c3f8a4d025acc8c857246ec2b812c59102487a", "status": "affected", "versionType": "git" }, { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "0e4c6faaef8a24b762a24ffb767280e263ef8e10", "status": "affected", "versionType": "git" }, { "version": "f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74", "lessThan": "eb02688c5c45c3e7af7e71f036a7144f5639cbfe", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/route.c" ], "versions": [ { "version": "5.3", "status": "affected" }, { "version": "0", "lessThan": "5.3", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.181", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.120", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.64", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.11", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.2", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "5.15.181" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.1.120" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.6.64" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.11.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.12.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.13" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/77aa9855a878fb43f547ddfbda3127a1e88ad31a" }, { "url": "https://git.kernel.org/stable/c/b2f26a27ea3f72f75d18330f76f5d1007c791848" }, { "url": "https://git.kernel.org/stable/c/43e25adc80269f917d2a195f0d59f74cdd182955" }, { "url": "https://git.kernel.org/stable/c/a3c3f8a4d025acc8c857246ec2b812c59102487a" }, { "url": "https://git.kernel.org/stable/c/0e4c6faaef8a24b762a24ffb767280e263ef8e10" }, { "url": "https://git.kernel.org/stable/c/eb02688c5c45c3e7af7e71f036a7144f5639cbfe" } ], "title": "ipv6: release nexthop on device removal", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T20:53:42.799Z" } } ] } }