CVE-2026-80841
In the Linux kernel, the following vulnerability has been resolved:
net/packet: defer vmalloc TX_RING free until skbs finish
AF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb page references preserve page-backed ring blocks after pg_vec is freed, but they do not preserve a vmalloc mapping.
tpacket_destruct_skb() currently drops the pending reference before writing the timestamp and TP_STATUS_AVAILABLE to the frame. Move the decrement after those stores. The smp_wmb() in __packet_set_status() orders the frame stores before the decrement.
Also recheck pending TX frames under pg_vec_lock before non-closing ring replacement, so a racing send cannot add a pending skb between the initial check and the ring swap.
Read full descriptionShow less
Ring allocation can produce a mixture of page-backed and vmalloc-backed blocks. Allocate deferred-work storage during TX ring setup when the first vmalloc-backed block is encountered, and keep its pointer in the pg_vec allocation header. If allocation fails, return -ENOMEM from ring setup. On socket close, a non-NULL pointer identifies a vmalloc-backed vector without a scan. If TX skbs remain, defer the whole vector to system_long_wq.
After pg_vec is detached, a late destructor can skip the pending decrement. Use socket write-memory accounting as the deferred lifetime gate instead: an skb remains charged through its final sock_wfree(), after all ring-frame accesses. The delayed work retains a socket reference and reschedules itself until no TX skbs remain.
Move pending_refcnt release to packet_sock_destruct() so late skb destructors and deferred cleanup can safely use it after packet_release(). Page-backed teardown remains synchronous, and no lock is added to the TX completion hot path.
CVSS
NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.17%
- Percentile among all scored CVEs: 6
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
References
- https://git.kernel.org/stable/c/0189dce07db2dc059ae0570e06758ec4233c6e11
- https://git.kernel.org/stable/c/4ce6e2d2e38055b2012bd5fdb0c8a8183c8a1b0c
- https://git.kernel.org/stable/c/550d00aa58193fb649a09a9c9e338c685adad784
- https://git.kernel.org/stable/c/992cc9f94ca924089a506ba9b327caa9af797529
- https://git.kernel.org/stable/c/debf9f50140b3df3949ebcb97d4450f8993fe32d
- https://git.kernel.org/stable/c/ed25ed29034ddc3dbe451ccbaa58ab9932f99d8b
Raw JSON (NVD)
Show
{
"id": "CVE-2026-80841",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "debf9f50140b3df3949ebcb97d4450f8993fe32d",
"versionType": "git"
},
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "4ce6e2d2e38055b2012bd5fdb0c8a8183c8a1b0c",
"versionType": "git"
},
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "ed25ed29034ddc3dbe451ccbaa58ab9932f99d8b",
"versionType": "git"
},
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "0189dce07db2dc059ae0570e06758ec4233c6e11",
"versionType": "git"
},
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "550d00aa58193fb649a09a9c9e338c685adad784",
"versionType": "git"
},
{
"status": "affected",
"version": "b013840810c221f2b0cf641d01531526052dc1fb",
"lessThan": "992cc9f94ca924089a506ba9b327caa9af797529",
"versionType": "git"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.14"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.111",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.51",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.13",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2.3",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/packet/af_packet.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-04T16:18:12.607",
"references": [
{
"url": "https://git.kernel.org/stable/c/0189dce07db2dc059ae0570e06758ec4233c6e11",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/4ce6e2d2e38055b2012bd5fdb0c8a8183c8a1b0c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/550d00aa58193fb649a09a9c9e338c685adad784",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/992cc9f94ca924089a506ba9b327caa9af797529",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/debf9f50140b3df3949ebcb97d4450f8993fe32d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ed25ed29034ddc3dbe451ccbaa58ab9932f99d8b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"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."
}
],
"lastModified": "2026-10-03T11:17:40.417",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}