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GHSA-5QR9-CJJ5-7M79

Vulnerability from github – Published: 2025-09-15 15:31 – Updated: 2025-12-03 21:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

xsk: check IFF_UP earlier in Tx path

Xsk Tx can be triggered via either sendmsg() or poll() syscalls. These two paths share a call to common function xsk_xmit() which has two sanity checks within. A pseudo code example to show the two paths:

__xsk_sendmsg() : xsk_poll(): if (unlikely(!xsk_is_bound(xs))) if (unlikely(!xsk_is_bound(xs))) return -ENXIO; return mask; if (unlikely(need_wait)) (...) return -EOPNOTSUPP; xsk_xmit() mark napi id (...) xsk_xmit()

xsk_xmit(): if (unlikely(!(xs->dev->flags & IFF_UP))) return -ENETDOWN; if (unlikely(!xs->tx)) return -ENOBUFS;

As it can be observed above, in sendmsg() napi id can be marked on interface that was not brought up and this causes a NULL ptr dereference:

[31757.505631] BUG: kernel NULL pointer dereference, address: 0000000000000018 [31757.512710] #PF: supervisor read access in kernel mode [31757.517936] #PF: error_code(0x0000) - not-present page [31757.523149] PGD 0 P4D 0 [31757.525726] Oops: 0000 [#1] PREEMPT SMP NOPTI [31757.530154] CPU: 26 PID: 95641 Comm: xdpsock Not tainted 6.2.0-rc5+ #40 [31757.536871] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [31757.547457] RIP: 0010:xsk_sendmsg+0xde/0x180 [31757.551799] Code: 00 75 a2 48 8b 00 a8 04 75 9b 84 d2 74 69 8b 85 14 01 00 00 85 c0 75 1b 48 8b 85 28 03 00 00 48 8b 80 98 00 00 00 48 8b 40 20 <8b> 40 18 89 85 14 01 00 00 8b bd 14 01 00 00 81 ff 00 01 00 00 0f [31757.570840] RSP: 0018:ffffc90034f27dc0 EFLAGS: 00010246 [31757.576143] RAX: 0000000000000000 RBX: ffffc90034f27e18 RCX: 0000000000000000 [31757.583389] RDX: 0000000000000001 RSI: ffffc90034f27e18 RDI: ffff88984cf3c100 [31757.590631] RBP: ffff88984714a800 R08: ffff88984714a800 R09: 0000000000000000 [31757.597877] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffffa [31757.605123] R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000000 [31757.612364] FS: 00007fb4c5931180(0000) GS:ffff88afdfa00000(0000) knlGS:0000000000000000 [31757.620571] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [31757.626406] CR2: 0000000000000018 CR3: 000000184b41c003 CR4: 00000000007706e0 [31757.633648] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [31757.640894] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [31757.648139] PKRU: 55555554 [31757.650894] Call Trace: [31757.653385] [31757.655524] sock_sendmsg+0x8f/0xa0 [31757.659077] ? sockfd_lookup_light+0x12/0x70 [31757.663416] __sys_sendto+0xfc/0x170 [31757.667051] ? do_sched_setscheduler+0xdb/0x1b0 [31757.671658] __x64_sys_sendto+0x20/0x30 [31757.675557] do_syscall_64+0x38/0x90 [31757.679197] entry_SYSCALL_64_after_hwframe+0x72/0xdc [31757.687969] Code: 8e f6 ff 44 8b 4c 24 2c 4c 8b 44 24 20 41 89 c4 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 3a 44 89 e7 48 89 44 24 08 e8 b5 8e f6 ff 48 [31757.707007] RSP: 002b:00007ffd49c73c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [31757.714694] RAX: ffffffffffffffda RBX: 000055a996565380 RCX: 00007fb4c5727c16 [31757.721939] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 [31757.729184] RBP: 0000000000000040 R08: 0000000000000000 R09: 0000000000000000 [31757.736429] R10: 0000000000000040 R11: 0000000000000293 R12: 0000000000000000 [31757.743673] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [31757.754940]

To fix this, let's make xsk_xmit a function that will be responsible for generic Tx, where RCU is handled accordingly and pull out sanity checks and xs->zc handling. Populate sanity checks to __xsk_sendmsg() and xsk_poll().

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-53240"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-09-15T15:15:51Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxsk: check IFF_UP earlier in Tx path\n\nXsk Tx can be triggered via either sendmsg() or poll() syscalls. These\ntwo paths share a call to common function xsk_xmit() which has two\nsanity checks within. A pseudo code example to show the two paths:\n\n__xsk_sendmsg() :                       xsk_poll():\nif (unlikely(!xsk_is_bound(xs)))        if (unlikely(!xsk_is_bound(xs)))\n    return -ENXIO;                          return mask;\nif (unlikely(need_wait))                (...)\n    return -EOPNOTSUPP;                 xsk_xmit()\nmark napi id\n(...)\nxsk_xmit()\n\nxsk_xmit():\nif (unlikely(!(xs-\u003edev-\u003eflags \u0026 IFF_UP)))\n\treturn -ENETDOWN;\nif (unlikely(!xs-\u003etx))\n\treturn -ENOBUFS;\n\nAs it can be observed above, in sendmsg() napi id can be marked on\ninterface that was not brought up and this causes a NULL ptr\ndereference:\n\n[31757.505631] BUG: kernel NULL pointer dereference, address: 0000000000000018\n[31757.512710] #PF: supervisor read access in kernel mode\n[31757.517936] #PF: error_code(0x0000) - not-present page\n[31757.523149] PGD 0 P4D 0\n[31757.525726] Oops: 0000 [#1] PREEMPT SMP NOPTI\n[31757.530154] CPU: 26 PID: 95641 Comm: xdpsock Not tainted 6.2.0-rc5+ #40\n[31757.536871] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019\n[31757.547457] RIP: 0010:xsk_sendmsg+0xde/0x180\n[31757.551799] Code: 00 75 a2 48 8b 00 a8 04 75 9b 84 d2 74 69 8b 85 14 01 00 00 85 c0 75 1b 48 8b 85 28 03 00 00 48 8b 80 98 00 00 00 48 8b 40 20 \u003c8b\u003e 40 18 89 85 14 01 00 00 8b bd 14 01 00 00 81 ff 00 01 00 00 0f\n[31757.570840] RSP: 0018:ffffc90034f27dc0 EFLAGS: 00010246\n[31757.576143] RAX: 0000000000000000 RBX: ffffc90034f27e18 RCX: 0000000000000000\n[31757.583389] RDX: 0000000000000001 RSI: ffffc90034f27e18 RDI: ffff88984cf3c100\n[31757.590631] RBP: ffff88984714a800 R08: ffff88984714a800 R09: 0000000000000000\n[31757.597877] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffffa\n[31757.605123] R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000000\n[31757.612364] FS:  00007fb4c5931180(0000) GS:ffff88afdfa00000(0000) knlGS:0000000000000000\n[31757.620571] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[31757.626406] CR2: 0000000000000018 CR3: 000000184b41c003 CR4: 00000000007706e0\n[31757.633648] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[31757.640894] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[31757.648139] PKRU: 55555554\n[31757.650894] Call Trace:\n[31757.653385]  \u003cTASK\u003e\n[31757.655524]  sock_sendmsg+0x8f/0xa0\n[31757.659077]  ? sockfd_lookup_light+0x12/0x70\n[31757.663416]  __sys_sendto+0xfc/0x170\n[31757.667051]  ? do_sched_setscheduler+0xdb/0x1b0\n[31757.671658]  __x64_sys_sendto+0x20/0x30\n[31757.675557]  do_syscall_64+0x38/0x90\n[31757.679197]  entry_SYSCALL_64_after_hwframe+0x72/0xdc\n[31757.687969] Code: 8e f6 ff 44 8b 4c 24 2c 4c 8b 44 24 20 41 89 c4 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 3a 44 89 e7 48 89 44 24 08 e8 b5 8e f6 ff 48\n[31757.707007] RSP: 002b:00007ffd49c73c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c\n[31757.714694] RAX: ffffffffffffffda RBX: 000055a996565380 RCX: 00007fb4c5727c16\n[31757.721939] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003\n[31757.729184] RBP: 0000000000000040 R08: 0000000000000000 R09: 0000000000000000\n[31757.736429] R10: 0000000000000040 R11: 0000000000000293 R12: 0000000000000000\n[31757.743673] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\n[31757.754940]  \u003c/TASK\u003e\n\nTo fix this, let\u0027s make xsk_xmit a function that will be responsible for\ngeneric Tx, where RCU is handled accordingly and pull out sanity checks\nand xs-\u003ezc handling. Populate sanity checks to __xsk_sendmsg() and\nxsk_poll().",
  "id": "GHSA-5qr9-cjj5-7m79",
  "modified": "2025-12-03T21:31:00Z",
  "published": "2025-09-15T15:31:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-53240"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1596dae2f17ec5c6e8c8f0e3fec78c5ae55c1e0b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cecc68559cd57fffb2be50685f262b9af2318e16"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ffe19750e68d0bb21e8110b398346eef20b156a7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}



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