{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2023-53641",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2023-53641"
  ],
  "published": "2025-10-07T15:20:13Z",
  "summary": "wifi: ath9k: hif_usb: fix memory leak of remain_skbs",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath9k: hif_usb: fix memory leak of remain_skbs\n\nhif_dev->remain_skb is allocated and used exclusively in\nath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is\nprocessed and subsequently freed (in error paths) only during the next\ncall of ath9k_hif_usb_rx_stream().\n\nSo, if the urbs are deallocated between those two calls due to the device\ndeinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream()\nis not called next time and the allocated remain_skb is leaked. Our local\nSyzkaller instance was able to trigger that.\n\nremain_skb makes sense when receiving two consecutive urbs which are\nlogically linked together, i.e. a specific data field from the first skb\nindicates a cached skb to be allocated, memcpy'd with some data and\nsubsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs\ndeallocation supposedly makes that link irrelevant so we need to free the\ncached skb in those cases.\n\nFix the leak by introducing a function to explicitly free remain_skb (if\nit is not NULL) when the rx urbs have been deallocated. remain_skb is NULL\nwhen it has not been allocated at all (hif_dev struct is kzalloced) or\nwhen it has been processed in next call to ath9k_hif_usb_rx_stream().\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.21-1+rpt1"
      ],
      "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"
          }
        ]
      },
      "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": "6.1.28"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-53641"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6719e3797ec52cd144c8a5ba8aaab36674800585"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d9899318660791141ea6002fda5577b2c5d7386e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/320d760a35273aa815d58b57e4fd9ba5279a3489"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/59073060fe0950c6ecbe12bdc06469dcac62128d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9b9356a3014123f0ce4b50d9278c1265173150ab"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f0931fc8f4b6847c72e170d2326861c0a081d680"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8f02d538878c9b1501f624595eb22ee4e5e0ff84"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/7654cc03eb699297130b693ec34e25f77b17c947"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-12T04:54:46Z"
  }
}