{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2023-53338",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2023-53338"
  ],
  "published": "2025-09-17T14:57:20Z",
  "summary": "lwt: Fix return values of BPF xmit ops",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nlwt: Fix return values of BPF xmit ops\n\nBPF encap ops can return different types of positive values, such like\nNET_RX_DROP, NET_XMIT_CN, NETDEV_TX_BUSY, and so on, from function\nskb_do_redirect and bpf_lwt_xmit_reroute. At the xmit hook, such return\nvalues would be treated implicitly as LWTUNNEL_XMIT_CONTINUE in\nip(6)_finish_output2. When this happens, skbs that have been freed would\ncontinue to the neighbor subsystem, causing use-after-free bug and\nkernel crashes.\n\nTo fix the incorrect behavior, skb_do_redirect return values can be\nsimply discarded, the same as tc-egress behavior. On the other hand,\nbpf_lwt_xmit_reroute returns useful errors to local senders, e.g. PMTU\ninformation. Thus convert its return values to avoid the conflict with\nLWTUNNEL_XMIT_CONTINUE.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.21-1+rpt1",
        "1:6.1.47-1+rpt2",
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi1-rpi-v6",
            "binary_version": "1:6.1.21-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi1-rpi-v7",
            "binary_version": "1:6.1.21-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi1-rpi-v7l",
            "binary_version": "1:6.1.21-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi1-rpi-v8",
            "binary_version": "1:6.1.21-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.21-1+rpt1": {
            "linux_commit": "0afb5e98488aed7017b9bf321b575d0177feb7ed",
            "upstream_version": "6.1.21",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.53"
          },
          "1:6.1.47-1+rpt2": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.53"
          },
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.53",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-53338"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/67f8f2bae8e7ac72e09def2b667e44704c4d1ee1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a97f221651fcdc891166e9bc270e3d9bfa5a0080"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e3f647e4b642f9f6d32795a16f92c116c138d2af"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/065d5f17096ec9161180e2c890afdff4dc6125f2"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d68c17402442f5f494a2c3ebde5cb82f6aa9160a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/65583f9e070db7bece20710cfa2e3daeb0b831d9"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/29b22badb7a84b783e3a4fffca16f7768fb31205"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T11:24:39Z"
  }
}