{"id":"CVE-2026-23379","summary":"net/sched: ets: fix divide by zero in the offload path","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' WRR weight: this is done by\naveraging over the sums of quanta as 'q_sum' and 'q_psum'. 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 'q_sum' and 'q_psum'.","modified":"2026-04-02T13:12:23.429545Z","published":"2026-03-25T10:27:58.659Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23379.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3912871344d6a0f1f572a7af2716968182d1e536"},{"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/a6677e23b313cd9fd03690c589c6452cb6fffb97"},{"type":"WEB","url":"https://git.kernel.org/stable/c/abe1d5cb7fe135c0862c58db32bc29e04cf1c906"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e35626f610f3d2b7953ccddf6a77453da22b3a9e"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23379.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23379"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d35eb52bd2ac7557b62bda52668f2e64dde2cf90"},{"fixed":"3912871344d6a0f1f572a7af2716968182d1e536"},{"fixed":"7dbffffd5761687e168fb2f4aaa7a2c47e067efc"},{"fixed":"78b8d2f55a564236435649fbd8bd6a103f30acf5"},{"fixed":"a6677e23b313cd9fd03690c589c6452cb6fffb97"},{"fixed":"abe1d5cb7fe135c0862c58db32bc29e04cf1c906"},{"fixed":"e35626f610f3d2b7953ccddf6a77453da22b3a9e"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23379.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.6.0"},{"fixed":"6.1.167"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.130"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.77"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.17"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23379.json"}}],"schema_version":"1.7.5"}