{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-38460",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2025-38460"
  ],
  "published": "2025-07-25T15:35:02Z",
  "summary": "atm: clip: Fix potential null-ptr-deref in to_atmarpd().",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\natm: clip: Fix potential null-ptr-deref in to_atmarpd().\n\natmarpd is protected by RTNL since commit f3a0592b37b8 (\"[ATM]: clip\ncauses unregister hang\").\n\nHowever, it is not enough because to_atmarpd() is called without RTNL,\nespecially clip_neigh_solicit() / neigh_ops->solicit() is unsleepable.\n\nAlso, there is no RTNL dependency around atmarpd.\n\nLet's use a private mutex and RCU to protect access to atmarpd in\nto_atmarpd().",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "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": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.146",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-38460"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a4c5785feb979cd996a99cfaad8bf353b2e79301"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/70eac9ba7ce25d99c1d99bbf4ddb058940f631f9"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/3251ce3979f41bd228f77a7615f9dd616d06a110"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ee4d9e4ddf3f9c4ee2ec0a3aad6196ee36d30e57"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/06935c50cfa3ac57cce80bba67b6d38ec1406e92"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/36caab990b69ef4eec1d81c52a19f080b7daa059"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f58e4270c73e7f086322978d585ea67c8076ce49"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/706cc36477139c1616a9b2b96610a8bb520b7119"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T12:19:11Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.0,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The race is driven from local context \u2014 an ATM socket's ATMARPD_CTRL open/close on one side and local packet transmission over the atm%d CLIP device (clip_start_xmit/clip_neigh_solicit) on the other. Received network packets can only supply one half of the race and give a remote party no influence over the teardown side, so Local is the accurate vector.\nAC:H - Scoring the security-meaningful attacker (unprivileged local user), the exploit requires being inside to_atmarpd() exactly while atmarpd_close() NULLs and frees the daemon's vcc \u2014 the daemon teardown is a system condition that an unprivileged attacker cannot induce, even though they can hammer the trigger path continuously.\nPR:L - No privileges are needed to reach the vulnerable function: any local user sending IP traffic to unresolved addresses on a configured CLIP interface drives clip_start_xmit()/clip_neigh_solicit() \u2192 to_atmarpd(). Only the administrative setup (SIOCMKCLIP/ATMARPD_CTRL, capable(CAP_NET_ADMIN)) is privileged, and that is the pre-existing deployment, not the attack.\nUI:N - No victim action is required \u2014 the attacker's own traffic triggers the vulnerable path, and the daemon-teardown condition is accounted for in Attack Complexity rather than user interaction.\nS:U - Both the flaw and its impact are confined to the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Winning the race leaves the racing thread operating on a freed struct atm_vcc/sock allocated from the generic kmalloc caches, and a use-after-free of a sprayable sock object can be leveraged to read kernel memory.\nI:H - The stale pointer is used for an atomic_add() write, an skb_queue_tail() list insertion into freed memory, and an indirect call through the freed sock's sk_data_ready() \u2014 a write primitive plus control-flow hijack after heap grooming.\nA:H - The minimum outcome is a kernel oops \u2014 a NULL (or freed) sock dereference in atm_force_charge()/skb_queue_tail() and a call through a NULL/garbage sk_data_ready pointer \u2014 panicking the system."
    }
  }
}