FKIE_CVE-2026-80742

Vulnerability from fkie_nvd - Published: 2026-09-03 13:06 - Updated: 2026-09-03 13:06
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: af_packet: Don't send zero-byte data in tpacket_snd(). syzbot reported a WARNING in __dev_queue_xmit() triggered via tpacket_snd(): skb_assert_len WARNING: at include/linux/skbuff.h:2753 skb_assert_len WARNING: at __dev_queue_xmit+0x21bc/0x4970 net/core/dev.c:4781 Call Trace: <TASK> dev_queue_xmit include/linux/netdevice.h:3448 [inline] packet_xmit+0x243/0x310 net/packet/af_packet.c:276 tpacket_snd net/packet/af_packet.c:2907 [inline] packet_sendmsg+0x28d6/0x4eb0 net/packet/af_packet.c:3134 When sending 0-byte packets via TPACKET ring buffer on devices with no hard header (e.g. dev->hard_header_len == 0), tpacket_fill_skb() populates an skb with skb->len == 0 and returns 0. tpacket_snd() then forwards this empty skb to packet_xmit(), causing __dev_queue_xmit() to hit skb_assert_len(skb). Similar checks exist in packet_snd() via commit dc633700f00f ("net/af_packet: check len when min_header_len equals to 0") and in packet_sendmsg_spkt() via commit 6a341729fb31 ("af_packet: Don't send zero-byte data in packet_sendmsg_spkt()."). Return -EINVAL in tpacket_fill_skb() when skb->len is zero to reject zero-length packets in tpacket_snd().
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1fc70b3d513bafb16b17540178870ef46e81c0bb
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3fa110f9e2ea96f567f2194c673c4bc327640111
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6bcd76c134c55c697148acb5c0194e9666abdf84
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7521e691c7c4f2231634c95053281ac888d1f452
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/80a702964467b998d254f16cc61c2c9a20540c9d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/98c5914d6b7bd4b4675535908e57dea31f1efd6a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/dde212f8622f5cb36223fff1ebd6e6f2a3dc61fe
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f09ac5682f1bb67981fcb6ead4d3cfe439225876
Impacted products
Vendor Product Version
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{
  "affected": [
    {
      "affectedData": [
        {
          "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": "dde212f8622f5cb36223fff1ebd6e6f2a3dc61fe",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "80a702964467b998d254f16cc61c2c9a20540c9d",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "7521e691c7c4f2231634c95053281ac888d1f452",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "1fc70b3d513bafb16b17540178870ef46e81c0bb",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "3fa110f9e2ea96f567f2194c673c4bc327640111",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "98c5914d6b7bd4b4675535908e57dea31f1efd6a",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "f09ac5682f1bb67981fcb6ead4d3cfe439225876",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "6bcd76c134c55c697148acb5c0194e9666abdf84",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "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": "2.6.12"
            },
            {
              "lessThan": "2.6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.266",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.217",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.184",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.153",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.105",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naf_packet: Don\u0027t send zero-byte data in tpacket_snd().\n\nsyzbot reported a WARNING in __dev_queue_xmit() triggered via tpacket_snd():\n\nskb_assert_len\nWARNING: at include/linux/skbuff.h:2753 skb_assert_len\nWARNING: at __dev_queue_xmit+0x21bc/0x4970 net/core/dev.c:4781\n\nCall Trace:\n \u003cTASK\u003e\n dev_queue_xmit include/linux/netdevice.h:3448 [inline]\n packet_xmit+0x243/0x310 net/packet/af_packet.c:276\n tpacket_snd net/packet/af_packet.c:2907 [inline]\n packet_sendmsg+0x28d6/0x4eb0 net/packet/af_packet.c:3134\n\nWhen sending 0-byte packets via TPACKET ring buffer on devices with no\nhard header (e.g. dev-\u003ehard_header_len == 0), tpacket_fill_skb()\npopulates an skb with skb-\u003elen == 0 and returns 0. tpacket_snd() then\nforwards this empty skb to packet_xmit(), causing __dev_queue_xmit() to\nhit skb_assert_len(skb).\n\nSimilar checks exist in packet_snd() via commit dc633700f00f\n(\"net/af_packet: check len when min_header_len equals to 0\") and in\npacket_sendmsg_spkt() via commit 6a341729fb31 (\"af_packet: Don\u0027t send\nzero-byte data in packet_sendmsg_spkt().\").\n\nReturn -EINVAL in tpacket_fill_skb() when skb-\u003elen is zero to reject\nzero-length packets in tpacket_snd()."
    }
  ],
  "id": "CVE-2026-80742",
  "lastModified": "2026-09-03T13:06:13.437",
  "metrics": {},
  "published": "2026-09-03T13:06:13.437",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1fc70b3d513bafb16b17540178870ef46e81c0bb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3fa110f9e2ea96f567f2194c673c4bc327640111"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6bcd76c134c55c697148acb5c0194e9666abdf84"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7521e691c7c4f2231634c95053281ac888d1f452"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/80a702964467b998d254f16cc61c2c9a20540c9d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/98c5914d6b7bd4b4675535908e57dea31f1efd6a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/dde212f8622f5cb36223fff1ebd6e6f2a3dc61fe"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f09ac5682f1bb67981fcb6ead4d3cfe439225876"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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