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GHSA-3P6H-G5J4-C7H7

Vulnerability from github – Published: 2026-03-25 12:30 – Updated: 2026-07-14 15:31
VLAI
Details

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

net/sched: ets: fix divide by zero in the offload path

Offloading ETS requires computing each class' WRR weight: this is done by averaging over the sums of quanta as 'q_sum' and 'q_psum'. Using unsigned int, the same integer size as the individual DRR quanta, can overflow and even cause division by zero, like it happened in the following splat:

Oops: divide error: 0000 [#1] SMP PTI CPU: 13 UID: 0 PID: 487 Comm: tc Tainted: G E 6.19.0-virtme #45 PREEMPT(full) Tainted: [E]=UNSIGNED_MODULE Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets] Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 <41> f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44 RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246 RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660 RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000 FS: 00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0 Call Trace: ets_qdisc_change+0x870/0xf40 [sch_ets] qdisc_create+0x12b/0x540 tc_modify_qdisc+0x6d7/0xbd0 rtnetlink_rcv_msg+0x168/0x6b0 netlink_rcv_skb+0x5c/0x110 netlink_unicast+0x1d6/0x2b0 netlink_sendmsg+0x22e/0x470 _syssendmsg+0x38a/0x3c0 _sys_sendmsg+0x99/0xe0 __sys_sendmsg+0x8a/0xf0 do_syscall_64+0x111/0xf80 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f440b81c77e Code: 4d 89 d8 e8 d4 bc 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa RSP: 002b:00007fff951e4c10 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000481820 RCX: 00007f440b81c77e RDX: 0000000000000000 RSI: 00007fff951e4cd0 RDI: 0000000000000003 RBP: 00007fff951e4c20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff951f4fa8 R13: 00000000699ddede R14: 00007f440bb01000 R15: 0000000000486980 Modules linked in: sch_ets(E) netdevsim(E) ---[ end trace 0000000000000000 ]--- RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets] Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 <41> f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44 RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246 RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660 RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000 FS: 00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0 Kernel panic - not syncing: Fatal exception Kernel Offset: 0x30000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) ---[ end Kernel panic - not syncing: Fatal exception ]---

Fix this using 64-bit integers for 'q_sum' and 'q_psum'.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2026-23379"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-369"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-25T11:16:37Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: fix divide by zero in the offload path\n\nOffloading ETS requires computing each class\u0027 WRR weight: this is done by\naveraging over the sums of quanta as \u0027q_sum\u0027 and \u0027q_psum\u0027. Using unsigned\nint, the same integer size as the individual DRR quanta, can overflow and\neven cause division by zero, like it happened in the following splat:\n\n Oops: divide error: 0000 [#1] SMP PTI\n CPU: 13 UID: 0 PID: 487 Comm: tc Tainted: G            E       6.19.0-virtme #45 PREEMPT(full)\n Tainted: [E]=UNSIGNED_MODULE\n Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets]\n Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 \u003c41\u003e f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44\n RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246\n RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660\n RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe\n R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe\n R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000\n FS:  00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0\n Call Trace:\n  \u003cTASK\u003e\n  ets_qdisc_change+0x870/0xf40 [sch_ets]\n  qdisc_create+0x12b/0x540\n  tc_modify_qdisc+0x6d7/0xbd0\n  rtnetlink_rcv_msg+0x168/0x6b0\n  netlink_rcv_skb+0x5c/0x110\n  netlink_unicast+0x1d6/0x2b0\n  netlink_sendmsg+0x22e/0x470\n  ____sys_sendmsg+0x38a/0x3c0\n  ___sys_sendmsg+0x99/0xe0\n  __sys_sendmsg+0x8a/0xf0\n  do_syscall_64+0x111/0xf80\n  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n RIP: 0033:0x7f440b81c77e\n Code: 4d 89 d8 e8 d4 bc 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 \u003cc9\u003e c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa\n RSP: 002b:00007fff951e4c10 EFLAGS: 00000202 ORIG_RAX: 000000000000002e\n RAX: ffffffffffffffda RBX: 0000000000481820 RCX: 00007f440b81c77e\n RDX: 0000000000000000 RSI: 00007fff951e4cd0 RDI: 0000000000000003\n RBP: 00007fff951e4c20 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff951f4fa8\n R13: 00000000699ddede R14: 00007f440bb01000 R15: 0000000000486980\n  \u003c/TASK\u003e\n Modules linked in: sch_ets(E) netdevsim(E)\n ---[ end trace 0000000000000000 ]---\n RIP: 0010:ets_offload_change+0x11f/0x290 [sch_ets]\n Code: e4 45 31 ff eb 03 41 89 c7 41 89 cb 89 ce 83 f9 0f 0f 87 b7 00 00 00 45 8b 08 31 c0 45 01 cc 45 85 c9 74 09 41 6b c4 64 31 d2 \u003c41\u003e f7 f2 89 c2 44 29 fa 45 89 df 41 83 fb 0f 0f 87 c7 00 00 00 44\n RSP: 0018:ffffd0a180d77588 EFLAGS: 00010246\n RAX: 00000000ffffff38 RBX: ffff8d3d482ca000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffd0a180d77660\n RBP: ffffd0a180d77690 R08: ffff8d3d482ca2d8 R09: 00000000fffffffe\n R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffe\n R13: ffff8d3d472f2000 R14: 0000000000000003 R15: 0000000000000000\n FS:  00007f440b6c2740(0000) GS:ffff8d3dc9803000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000003cdd2000 CR3: 0000000007b58002 CR4: 0000000000172ef0\n Kernel panic - not syncing: Fatal exception\n Kernel Offset: 0x30000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)\n ---[ end Kernel panic - not syncing: Fatal exception ]---\n\nFix this using 64-bit integers for \u0027q_sum\u0027 and \u0027q_psum\u0027.",
  "id": "GHSA-3p6h-g5j4-c7h7",
  "modified": "2026-07-14T15:31:43Z",
  "published": "2026-03-25T12:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23379"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3912871344d6a0f1f572a7af2716968182d1e536"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/62015c05878eb9ca448dca7f5a74423d10d40789"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/78b8d2f55a564236435649fbd8bd6a103f30acf5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7dbffffd5761687e168fb2f4aaa7a2c47e067efc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a11ec75a029b3a22b5596f98ce91a3be76a86213"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a6677e23b313cd9fd03690c589c6452cb6fffb97"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/abe1d5cb7fe135c0862c58db32bc29e04cf1c906"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e35626f610f3d2b7953ccddf6a77453da22b3a9e"
    }
  ],
  "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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