{"api_version":"1","generated_at":"2026-09-09T06:27:26+00:00","cve":"CVE-2026-80841","urls":{"html":"https://cve.report/CVE-2026-80841","api":"https://cve.report/api/cve/CVE-2026-80841.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-80841","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-80841"},"summary":{"title":"net/packet: defer vmalloc TX_RING free until skbs finish","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: defer vmalloc TX_RING free until skbs finish\n\nAF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb\npage references preserve page-backed ring blocks after pg_vec is freed,\nbut they do not preserve a vmalloc mapping.\n\ntpacket_destruct_skb() currently drops the pending reference before\nwriting the timestamp and TP_STATUS_AVAILABLE to the frame. Move the\ndecrement after those stores. The smp_wmb() in __packet_set_status()\norders the frame stores before the decrement.\n\nAlso recheck pending TX frames under pg_vec_lock before non-closing\nring replacement, so a racing send cannot add a pending skb between\nthe initial check and the ring swap.\n\nRing allocation can produce a mixture of page-backed and vmalloc-backed\nblocks. Allocate deferred-work storage during TX ring setup when the\nfirst vmalloc-backed block is encountered, and keep its pointer in the\npg_vec allocation header. If allocation fails, return -ENOMEM from ring\nsetup. On socket close, a non-NULL pointer identifies a vmalloc-backed\nvector without a scan. If TX skbs remain, defer the whole vector to\nsystem_long_wq.\n\nAfter pg_vec is detached, a late destructor can skip the pending\ndecrement. Use socket write-memory accounting as the deferred lifetime\ngate instead: an skb remains charged through its final sock_wfree(),\nafter all ring-frame accesses. The delayed work retains a socket\nreference and reschedules itself until no TX skbs remain.\n\nMove pending_refcnt release to packet_sock_destruct() so late skb\ndestructors and deferred cleanup can safely use it after\npacket_release(). Page-backed teardown remains synchronous, and no lock\nis added to the TX completion hot path.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-04 16:18:12","updated_at":"2026-09-04 16:18:12"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/0189dce07db2dc059ae0570e06758ec4233c6e11","name":"https://git.kernel.org/stable/c/0189dce07db2dc059ae0570e06758ec4233c6e11","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/550d00aa58193fb649a09a9c9e338c685adad784","name":"https://git.kernel.org/stable/c/550d00aa58193fb649a09a9c9e338c685adad784","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/992cc9f94ca924089a506ba9b327caa9af797529","name":"https://git.kernel.org/stable/c/992cc9f94ca924089a506ba9b327caa9af797529","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80841","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80841","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b013840810c221f2b0cf641d01531526052dc1fb 0189dce07db2dc059ae0570e06758ec4233c6e11 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b013840810c221f2b0cf641d01531526052dc1fb 550d00aa58193fb649a09a9c9e338c685adad784 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b013840810c221f2b0cf641d01531526052dc1fb 992cc9f94ca924089a506ba9b327caa9af797529 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.13 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.3 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"80841","cve":"CVE-2026-80841","epss":"0.001660000","percentile":"0.061330000","score_date":"2026-09-07","updated_at":"2026-09-08 00:05:27"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"0189dce07db2dc059ae0570e06758ec4233c6e11","status":"affected","version":"b013840810c221f2b0cf641d01531526052dc1fb","versionType":"git"},{"lessThan":"550d00aa58193fb649a09a9c9e338c685adad784","status":"affected","version":"b013840810c221f2b0cf641d01531526052dc1fb","versionType":"git"},{"lessThan":"992cc9f94ca924089a506ba9b327caa9af797529","status":"affected","version":"b013840810c221f2b0cf641d01531526052dc1fb","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/packet/af_packet.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.14"},{"lessThan":"3.14","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.13","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.3","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.13","versionStartIncluding":"3.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.3","versionStartIncluding":"3.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"3.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: defer vmalloc TX_RING free until skbs finish\n\nAF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb\npage references preserve page-backed ring blocks after pg_vec is freed,\nbut they do not preserve a vmalloc mapping.\n\ntpacket_destruct_skb() currently drops the pending reference before\nwriting the timestamp and TP_STATUS_AVAILABLE to the frame. Move the\ndecrement after those stores. The smp_wmb() in __packet_set_status()\norders the frame stores before the decrement.\n\nAlso recheck pending TX frames under pg_vec_lock before non-closing\nring replacement, so a racing send cannot add a pending skb between\nthe initial check and the ring swap.\n\nRing allocation can produce a mixture of page-backed and vmalloc-backed\nblocks. Allocate deferred-work storage during TX ring setup when the\nfirst vmalloc-backed block is encountered, and keep its pointer in the\npg_vec allocation header. If allocation fails, return -ENOMEM from ring\nsetup. On socket close, a non-NULL pointer identifies a vmalloc-backed\nvector without a scan. If TX skbs remain, defer the whole vector to\nsystem_long_wq.\n\nAfter pg_vec is detached, a late destructor can skip the pending\ndecrement. Use socket write-memory accounting as the deferred lifetime\ngate instead: an skb remains charged through its final sock_wfree(),\nafter all ring-frame accesses. The delayed work retains a socket\nreference and reschedules itself until no TX skbs remain.\n\nMove pending_refcnt release to packet_sock_destruct() so late skb\ndestructors and deferred cleanup can safely use it after\npacket_release(). Page-backed teardown remains synchronous, and no lock\nis added to the TX completion hot path."}],"providerMetadata":{"dateUpdated":"2026-09-04T15:54:51.459Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/0189dce07db2dc059ae0570e06758ec4233c6e11"},{"url":"https://git.kernel.org/stable/c/550d00aa58193fb649a09a9c9e338c685adad784"},{"url":"https://git.kernel.org/stable/c/992cc9f94ca924089a506ba9b327caa9af797529"}],"title":"net/packet: defer vmalloc TX_RING free until skbs finish","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-80841","datePublished":"2026-09-04T15:54:51.459Z","dateReserved":"2026-08-26T14:34:25.796Z","dateUpdated":"2026-09-04T15:54:51.459Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-04 16:18:12","lastModifiedDate":"2026-09-04 16:18:12","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"80841","Ordinal":"1","Title":"net/packet: defer vmalloc TX_RING free until skbs finish","CVE":"CVE-2026-80841","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"80841","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: defer vmalloc TX_RING free until skbs finish\n\nAF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb\npage references preserve page-backed ring blocks after pg_vec is freed,\nbut they do not preserve a vmalloc mapping.\n\ntpacket_destruct_skb() currently drops the pending reference before\nwriting the timestamp and TP_STATUS_AVAILABLE to the frame. Move the\ndecrement after those stores. The smp_wmb() in __packet_set_status()\norders the frame stores before the decrement.\n\nAlso recheck pending TX frames under pg_vec_lock before non-closing\nring replacement, so a racing send cannot add a pending skb between\nthe initial check and the ring swap.\n\nRing allocation can produce a mixture of page-backed and vmalloc-backed\nblocks. Allocate deferred-work storage during TX ring setup when the\nfirst vmalloc-backed block is encountered, and keep its pointer in the\npg_vec allocation header. If allocation fails, return -ENOMEM from ring\nsetup. On socket close, a non-NULL pointer identifies a vmalloc-backed\nvector without a scan. If TX skbs remain, defer the whole vector to\nsystem_long_wq.\n\nAfter pg_vec is detached, a late destructor can skip the pending\ndecrement. Use socket write-memory accounting as the deferred lifetime\ngate instead: an skb remains charged through its final sock_wfree(),\nafter all ring-frame accesses. The delayed work retains a socket\nreference and reschedules itself until no TX skbs remain.\n\nMove pending_refcnt release to packet_sock_destruct() so late skb\ndestructors and deferred cleanup can safely use it after\npacket_release(). Page-backed teardown remains synchronous, and no lock\nis added to the TX completion hot path.","Type":"Description","Title":"net/packet: defer vmalloc TX_RING free until skbs finish"}]}}}