udp: clear skb->dev before running a sockmap verdict_CVE-2026-53184

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nudp: clear skb->dev before running a sockmap verdict\n\nOn the UDP receive path skb->dev is repurposed as dev_scratch (the\ntruesize/state cache set by udp_set_dev_scratch()), through the\nunion { struct net_device *dev; unsigned long dev_scratch; } in sk_buff.\n\nWhen a UDP socket is in a sockmap, sk_data_ready is\nsk_psock_verdict_data_ready(), which calls udp_read_skb() -> recv_actor()\n(sk_psock_verdict_recv) to run the attached SK_SKB verdict program in softirq.\nIf that program calls a socket-lookup helper (bpf_sk_lookup_tcp/udp,\nbpf_skc_lookup_tcp), bpf_skc_lookup() does:\n\n\tif (skb->dev)\n\t\tcaller_net = dev_net(skb->dev);\n\nskb->dev still holds the dev_scratch value (a non-NULL integer), so dev_net()\ndereferences it as a struct net_device * and the kernel takes a general\nprotection fault on a non-canonical address in softirq:\n\n  Oops: general protection fault, probably for non-canonical address 0x1010000800004a0\n  CPU: 1 UID: 0 PID: 1406 Comm: syz.2.19 Not tainted 7.1.0-rc6 #1 PREEMPT(full)\n  RIP: 0010:bpf_skc_lookup net/core/filter.c:7033 [inline]\n  RIP: 0010:bpf_sk_lookup+0x45/0x160 net/core/filter.c:7047\n  Call Trace:\n   <IRQ>\n   bpf_prog_4675cb904b7071f8+0x12e/0x14e\n   bpf_prog_run_pin_on_cpu+0xc6/0x1f0\n   sk_psock_verdict_recv+0x1ba/0x350\n   udp_read_skb+0x31a/0x370\n   sk_psock_verdict_data_ready+0x2e3/0x600\n   __udp_enqueue_schedule_skb+0x4c8/0x650\n   udpv6_queue_rcv_one_skb+0x3ec/0x740\n   udp6_unicast_rcv_skb+0x11d/0x140\n   ip6_protocol_deliver_rcu+0x61e/0x950\n   ip6_input_finish+0xa9/0x150\n   NF_HOOK+0x286/0x2f0\n   ip6_input+0x117/0x220\n   NF_HOOK+0x286/0x2f0\n   __netif_receive_skb+0x85/0x200\n   process_backlog+0x374/0x9a0\n   __napi_poll+0x4f/0x1c0\n   net_rx_action+0x3b0/0x770\n   handle_softirqs+0x15a/0x460\n   do_softirq+0x57/0x80\n   </IRQ>\n\nThe rmem charge that dev_scratch accounted for is released by skb_recv_udp() on\ndequeue, just above, so the scratch is dead by the time recv_actor() runs. Clear\nskb->dev so bpf_skc_lookup() falls back to sock_net(skb->sk), which\nskb_set_owner_sk_safe() set just above.",
    "published": "2026-06-25T08:38:58.189Z",
    "modified": "2026-06-28T06:39:58.363Z",
    "type": "cve",
    "title": "udp: clear skb->dev before running a sockmap verdict",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/263779a6beff03b8b06f6d25566cb0f45af361f2\nhttps://git.kernel.org/stable/c/1b585673a2249f13678e7ac443ac683ba767e0b6\nhttps://git.kernel.org/stable/c/90d35188aaa92b8f8b23f66335e0e91bf60103a3\nhttps://git.kernel.org/stable/c/6822eed69572000a181fa4e31fceacc60918c471\nhttps://git.kernel.org/stable/c/7d6d92d000ebe3a845a17c165c1d3a70c5d84fe1\nhttps://git.kernel.org/stable/c/3c94f241f776562c489876ff506f366224565c21",
    "id": "CVE-2026-53184",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 965b57b469a589d64d81b1688b38dcb537011bb0\nLinux Linux 6.0",
    "sourceHref": "",
    "cvss": {
        "score": 7.5,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
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            "privilegesRequired": "",
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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "965b57b469a589d64d81b1688b38dcb537011bb0",
    "vendor": "Linux",
    "ai_description": "",
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    "ai_score": 0
}