{"id":"CVE-2026-23379","title":"net/sched: ets: fix divide by zero in the offload path","summary":"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 '…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 62015c05878eb9ca448dca7f5a74423d10d40789","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < a11ec75a029b3a22b5596f98ce91a3be76a86213","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 3912871344d6a0f1f572a7af2716968182d1e536","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 7dbffffd5761687e168fb2f4aaa7a2c47e067efc","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 78b8d2f55a564236435649fbd8bd6a103f30acf5","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < a6677e23b313cd9fd03690c589c6452cb6fffb97","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < abe1d5cb7fe135c0862c58db32bc29e04cf1c906","Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < e35626f610f3d2b7953ccddf6a77453da22b3a9e","Linux 5.6"],"published":"2026-03-25","updated":"2026-09-08","sourceUpdated":"2026-09-08T08:45:51.673Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23379","references":[{"url":"https://git.kernel.org/stable/c/62015c05878eb9ca448dca7f5a74423d10d40789"},{"url":"https://git.kernel.org/stable/c/a11ec75a029b3a22b5596f98ce91a3be76a86213"},{"url":"https://git.kernel.org/stable/c/3912871344d6a0f1f572a7af2716968182d1e536"},{"url":"https://git.kernel.org/stable/c/7dbffffd5761687e168fb2f4aaa7a2c47e067efc"},{"url":"https://git.kernel.org/stable/c/78b8d2f55a564236435649fbd8bd6a103f30acf5"},{"url":"https://git.kernel.org/stable/c/a6677e23b313cd9fd03690c589c6452cb6fffb97"},{"url":"https://git.kernel.org/stable/c/abe1d5cb7fe135c0862c58db32bc29e04cf1c906"},{"url":"https://git.kernel.org/stable/c/e35626f610f3d2b7953ccddf6a77453da22b3a9e"}],"tags":["cve.org"],"epss":0.00125,"epssPercentile":0.02557,"ingestedAt":"2026-09-08T15:33:26.992Z","slug":"CVE-2026-23379","body":"## Overview\n\nIn 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 <41> 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 \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 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 \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 <41> 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'.\n\n## Affected\n\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 62015c05878eb9ca448dca7f5a74423d10d40789`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < a11ec75a029b3a22b5596f98ce91a3be76a86213`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 3912871344d6a0f1f572a7af2716968182d1e536`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 7dbffffd5761687e168fb2f4aaa7a2c47e067efc`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < 78b8d2f55a564236435649fbd8bd6a103f30acf5`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < a6677e23b313cd9fd03690c589c6452cb6fffb97`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < abe1d5cb7fe135c0862c58db32bc29e04cf1c906`\n- `Linux >= d35eb52bd2ac7557b62bda52668f2e64dde2cf90 < e35626f610f3d2b7953ccddf6a77453da22b3a9e`\n- `Linux 5.6`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}