{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-21706",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2025-21706"
  ],
  "published": "2025-02-27T02:06:37Z",
  "summary": "mptcp: pm: only set fullmesh for subflow endp",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: only set fullmesh for subflow endp\n\nWith the in-kernel path-manager, it is possible to change the 'fullmesh'\nflag. The code in mptcp_pm_nl_fullmesh() expects to change it only on\n'subflow' endpoints, to recreate more or less subflows using the linked\naddress.\n\nUnfortunately, the set_flags() hook was a bit more permissive, and\nallowed 'implicit' endpoints to get the 'fullmesh' flag while it is not\nallowed before.\n\nThat's what syzbot found, triggering the following warning:\n\n  WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 __mark_subflow_endp_available net/mptcp/pm_netlink.c:1496 [inline]\n  WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_pm_nl_fullmesh net/mptcp/pm_netlink.c:1980 [inline]\n  WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_nl_set_flags net/mptcp/pm_netlink.c:2003 [inline]\n  WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_pm_nl_set_flags+0x974/0xdc0 net/mptcp/pm_netlink.c:2064\n  Modules linked in:\n  CPU: 0 UID: 0 PID: 6499 Comm: syz.1.413 Not tainted 6.13.0-rc5-syzkaller-00172-gd1bf27c4e176 #0\n  Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\n  RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_netlink.c:1496 [inline]\n  RIP: 0010:mptcp_pm_nl_fullmesh net/mptcp/pm_netlink.c:1980 [inline]\n  RIP: 0010:mptcp_nl_set_flags net/mptcp/pm_netlink.c:2003 [inline]\n  RIP: 0010:mptcp_pm_nl_set_flags+0x974/0xdc0 net/mptcp/pm_netlink.c:2064\n  Code: 01 00 00 49 89 c5 e8 fb 45 e8 f5 e9 b8 fc ff ff e8 f1 45 e8 f5 4c 89 f7 be 03 00 00 00 e8 44 1d 0b f9 eb a0 e8 dd 45 e8 f5 90 <0f> 0b 90 e9 17 ff ff ff 89 d9 80 e1 07 38 c1 0f 8c c9 fc ff ff 48\n  RSP: 0018:ffffc9000d307240 EFLAGS: 00010293\n  RAX: ffffffff8bb72e03 RBX: 0000000000000000 RCX: ffff88807da88000\n  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\n  RBP: ffffc9000d307430 R08: ffffffff8bb72cf0 R09: 1ffff1100b842a5e\n  R10: dffffc0000000000 R11: ffffed100b842a5f R12: ffff88801e2e5ac0\n  R13: ffff88805c214800 R14: ffff88805c2152e8 R15: 1ffff1100b842a5d\n  FS:  00005555619f6500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 0000000020002840 CR3: 00000000247e6000 CR4: 00000000003526f0\n  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n  Call Trace:\n   <TASK>\n   genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]\n   genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]\n   genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210\n   netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542\n   genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219\n   netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]\n   netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347\n   netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891\n   sock_sendmsg_nosec net/socket.c:711 [inline]\n   __sock_sendmsg+0x221/0x270 net/socket.c:726\n   ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583\n   ___sys_sendmsg net/socket.c:2637 [inline]\n   __sys_sendmsg+0x269/0x350 net/socket.c:2669\n   do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n  RIP: 0033:0x7f5fe8785d29\n  Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\n  RSP: 002b:00007fff571f5558 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\n  RAX: ffffffffffffffda RBX: 00007f5fe8975fa0 RCX: 00007f5fe8785d29\n  RDX: 0000000000000000 RSI: 0000000020000480 RDI: 0000000000000007\n  RBP: 00007f5fe8801b08 R08: 0000000000000000 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\n  R13: 00007f5fe8975fa0 R14: 00007f5fe8975fa0 R15: 000000\n---truncated---",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt2",
        "1:6.1.47-1+rpt4",
        "1:6.1.54-1+rpt2",
        "1:6.1.58-1+rpt2",
        "1:6.1.63-1+rpt1",
        "1:6.1.73-1+rpt1",
        "1:6.6.20-1+rpt1",
        "1:6.6.28-1+rpt1",
        "1:6.6.31-1+rpt1",
        "1:6.6.47-1+rpt1",
        "1:6.6.51-1+rpt1",
        "1:6.6.51-1+rpt2",
        "1:6.6.51-1+rpt3",
        "1:6.6.62-1+rpt1",
        "1:6.6.74-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
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            "binary_version": "1:6.1.47-1+rpt4"
          },
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            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
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            "binary_version": "1:6.1.47-1+rpt4"
          },
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            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
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            "binary_version": "1:6.1.47-1+rpt4"
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            "binary_version": "1:6.1.54-1+rpt2"
          },
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            "binary_version": "1:6.1.58-1+rpt2"
          },
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          },
          {
            "binary_name": "linux-image-6.6.20+rpt-rpi-2712",
            "binary_version": "1:6.6.20-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.20+rpt-rpi-v8",
            "binary_version": "1:6.6.20-1+rpt1"
          },
          {
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            "binary_version": "1:6.6.28-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.28+rpt-rpi-v8",
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          },
          {
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          },
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          },
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          },
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            "binary_version": "1:6.6.51-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.6.51+rpt-rpi-2712",
            "binary_version": "1:6.6.51-1+rpt2"
          },
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            "binary_name": "linux-image-6.6.51+rpt-rpi-v8",
            "binary_version": "1:6.6.51-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.6.51+rpt-rpi-2712",
            "binary_version": "1:6.6.51-1+rpt3"
          },
          {
            "binary_name": "linux-image-6.6.51+rpt-rpi-v8",
            "binary_version": "1:6.6.51-1+rpt3"
          },
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            "binary_version": "1:6.6.62-1+rpt1"
          },
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            "binary_name": "linux-image-6.6.62+rpt-rpi-v8",
            "binary_version": "1:6.6.62-1+rpt1"
          },
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            "binary_name": "linux-image-6.6.74+rpt-rpi-2712",
            "binary_version": "1:6.6.74-1+rpt1"
          },
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            "binary_version": "1:6.6.74-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt2": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.129"
          },
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.129",
            "compiled_filter": false
          },
          "1:6.1.54-1+rpt2": {
            "linux_commit": "2906f7abdc03d4a92b6b0e2e0c87ea2a9dffe8f7",
            "upstream_version": "6.1.54",
            "assessment": "commit ancestry (strak rule)",
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          },
          "1:6.1.58-1+rpt2": {
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            "upstream_version": "6.1.58",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.129"
          },
          "1:6.1.63-1+rpt1": {
            "linux_commit": null,
            "upstream_version": "6.1.63",
            "assessment": "upstream version (no usable Linux commit)",
            "upstream_fixed": "6.1.129"
          },
          "1:6.1.73-1+rpt1": {
            "linux_commit": null,
            "upstream_version": "6.1.73",
            "assessment": "upstream version (no usable Linux commit)",
            "upstream_fixed": "6.1.129"
          },
          "1:6.6.20-1+rpt1": {
            "linux_commit": "6f16847710cc0502450788b9f12f0a14d3429668",
            "upstream_version": "6.6.20",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
          "1:6.6.28-1+rpt1": {
            "linux_commit": "0c341f47adc3578cd5f817aa20ee2b7f9ae6b23e",
            "upstream_version": "6.6.28",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
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            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
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            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
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            "assessment": "commit ancestry (strak rule)",
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          },
          "1:6.6.51-1+rpt2": {
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            "upstream_version": "6.6.51",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
          "1:6.6.51-1+rpt3": {
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            "upstream_version": "6.6.51",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
          "1:6.6.62-1+rpt1": {
            "linux_commit": "dd2394360860d15146c96635796a75b05bb32b61",
            "upstream_version": "6.6.62",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          },
          "1:6.6.74-1+rpt1": {
            "linux_commit": "a18d9ced4965462cb7b3b4252ada440395105308",
            "upstream_version": "6.6.74",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.6.78"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-21706"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/22b0734c9401a74ed4ebd9e8ef0da33e493852eb"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/de3b8d41d2547452c4cafb146d003fa4689fbaf2"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8ac344cbd84fda75e05e1f445f7f8fb24dc175e1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9e3d61620a3cd033319553b980ff3a350adbe1bc"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/1bb0d1348546ad059f55c93def34e67cb2a034a6"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-05-12T04:54:46Z"
  }
}
