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CVE-2026-98850

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/packet: prevent TX_RING byte count overflow tpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds each valid packet length to the signed int len_sum. Userspace can recycle completed frames concurrently, so a single blocking send call is not bounded by the ring size. After enough successful transmissions len_sum wraps into the negative range. In particular, 65536 65535-byte frames followed by a 65007-byte frame produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats that as an impossible return and triggers a BUG. On systems configured to panic on oops, a CAP_NET_RAW holder can panic the host kernel. Stop before the next frame would make the byte count exceed INT_MAX. The positive short count leaves that frame pending for a later send call. A two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build of Linux 7.3-rc4. With this change, the same reproducer returned the expected positive short count without an oops.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-10-18 16:17:39.390000
Last modified
2026-10-30 13:21:30.597000
View original CVE JSON
{
  "id": "CVE-2026-98850",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-18T16:17:39.390",
  "lastModified": "2026-10-30T13:21:30.597",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: prevent TX_RING byte count overflow\n\ntpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds\neach valid packet length to the signed int len_sum. Userspace can\nrecycle completed frames concurrently, so a single blocking send call\nis not bounded by the ring size.\n\nAfter enough successful transmissions len_sum wraps into the negative\nrange. In particular, 65536 65535-byte frames followed by a 65007-byte\nframe produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats\nthat as an impossible return and triggers a BUG. On systems configured\nto panic on oops, a CAP_NET_RAW holder can panic the host kernel.\n\nStop before the next frame would make the byte count exceed INT_MAX.\nThe positive short count leaves that frame pending for a later send\ncall.\n\nA two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build\nof Linux 7.3-rc4. With this change, the same reproducer returned the\nexpected positive short count without an oops."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/packet/af_packet.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "1e6ee93cea4b77253b1b81eb5759899f959ebee3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "70fefff0801d4c5405e515592d1e7ad1351530cd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "4848c175b5984e6358bcca794ac1dee4d527efcc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "ae169d318d5d23bac76ece90a7e2b5cb760ed043",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "be12b221c0301111eeb023be04add3c6ad7c21fe",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "69ca64bbb528898916f309552053c32a04a36ebc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "9fd63d284e251332f4874ef9023cde472f315f86",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1",
              "lessThan": "2cf81fc9505b148b1b70068303ea6ea4b1212403",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/packet/af_packet.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.31",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.31",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.273",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.224",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.113",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.56",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.10",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1e6ee93cea4b77253b1b81eb5759899f959ebee3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2cf81fc9505b148b1b70068303ea6ea4b1212403",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4848c175b5984e6358bcca794ac1dee4d527efcc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/69ca64bbb528898916f309552053c32a04a36ebc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/70fefff0801d4c5405e515592d1e7ad1351530cd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9fd63d284e251332f4874ef9023cde472f315f86",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ae169d318d5d23bac76ece90a7e2b5cb760ed043",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/be12b221c0301111eeb023be04add3c6ad7c21fe",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}