{"id":"CVE-2026-98881","title":"net: bridge: remove stale rcu_barrier() in br_multicast_dev_del()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: remove stale rcu_barrier() in br_multicast_dev_del()\n\nThis rcu_barrier() came from a time call_rcu() calls were used in\nnet/bridge/br_multicast.c.\n\nNow kfr…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 35f9f11740515a10b084adfb1ce691351f2452ab","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0443f6aac6bf6a91e406273fdda11497cef6ad07","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ac0e823a228f94ad9d7a3d876cc07e59a7afb806","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f0018acf0b66f93a292667c9a9c2a26c570cf270","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 372ee8fbe0f796031c60f676ec90f0788c26523d","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 39679927fa7aaf4601119f7234342d1b5d4f6f84","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 25ae123db10ba9ab890b56bcdb0a4363aee8529a","Linux < 5.10.271","Linux < 5.15.222","Linux < 6.1.189","Linux < 6.6.158","Linux < 6.12.111","Linux < 6.18.53","Linux (all versions)"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T11:37:32.327Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98881","references":[{"url":"https://git.kernel.org/stable/c/35f9f11740515a10b084adfb1ce691351f2452ab"},{"url":"https://git.kernel.org/stable/c/0443f6aac6bf6a91e406273fdda11497cef6ad07"},{"url":"https://git.kernel.org/stable/c/ac0e823a228f94ad9d7a3d876cc07e59a7afb806"},{"url":"https://git.kernel.org/stable/c/f0018acf0b66f93a292667c9a9c2a26c570cf270"},{"url":"https://git.kernel.org/stable/c/372ee8fbe0f796031c60f676ec90f0788c26523d"},{"url":"https://git.kernel.org/stable/c/39679927fa7aaf4601119f7234342d1b5d4f6f84"},{"url":"https://git.kernel.org/stable/c/25ae123db10ba9ab890b56bcdb0a4363aee8529a"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T13:24:55.582Z","slug":"CVE-2026-98881","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: remove stale rcu_barrier() in br_multicast_dev_del()\n\nThis rcu_barrier() came from a time call_rcu() calls were used in\nnet/bridge/br_multicast.c.\n\nNow kfree_rcu() is there, we can remove this problematic rcu_barrier()\nwhich causes extreme RTNL pressure in many syzbot reports.\n\nINFO: task syz-executor:77945 is blocked on a mutex likely owned by task kworker/u1024:5:36537.\ntask:kworker/u1024:5 state:D stack:24616 pid:36537 tgid:36537 ppid:2      task_flags:0x4208060 flags:0x00080000 last_sleep:612797637337\nWorkqueue: netns cleanup_net\nCall Trace:\n <TASK>\n  [<ffffffff81914eaa>] context_switch+0xf2a/0x1730 kernel/sched/core.c:6483\n  [<ffffffff81201143>] __schedule+0x1133/0x43a0 kernel/sched/core.c:8411\n  [<ffffffff8120446b>] __schedule_loop kernel/sched/core.c:8514 [inline]\n  [<ffffffff8120446b>] schedule+0xab/0x260 kernel/sched/core.c:8529\n  [<ffffffff8121a093>] schedule_timeout+0xc3/0x2b0 kernel/time/sleep_timeout.c:75\n  [<ffffffff81205347>] do_wait_for_common kernel/sched/completion.c:100 [inline]\n  [<ffffffff81205347>] __wait_for_common kernel/sched/completion.c:121 [inline]\n  [<ffffffff81205347>] wait_for_common kernel/sched/completion.c:132 [inline]\n  [<ffffffff81205347>] wait_for_completion+0x2c7/0x5d0 kernel/sched/completion.c:153\n  [<ffffffff81b8f27f>] rcu_barrier+0x49f/0x620 kernel/rcu/tree.c:3888\n  [<ffffffff860091b3>] br_multicast_dev_del+0x303/0x350 net/bridge/br_multicast.c:4459\n  [<ffffffff85fb5dbc>] br_dev_uninit+0x1c/0x40 net/bridge/br_device.c:157\n  [<ffffffff8568058c>] unregister_netdevice_many_notify+0x1c1c/0x2300 net/core/dev.c:12599\n  [<ffffffff8562be43>] ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]\n  [<ffffffff8562be43>] ops_undo_list+0x3d3/0x940 net/core/net_namespace.c:248\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 35f9f11740515a10b084adfb1ce691351f2452ab`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0443f6aac6bf6a91e406273fdda11497cef6ad07`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ac0e823a228f94ad9d7a3d876cc07e59a7afb806`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f0018acf0b66f93a292667c9a9c2a26c570cf270`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 372ee8fbe0f796031c60f676ec90f0788c26523d`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 39679927fa7aaf4601119f7234342d1b5d4f6f84`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 25ae123db10ba9ab890b56bcdb0a4363aee8529a`\n- `Linux < 5.10.271`\n- `Linux < 5.15.222`\n- `Linux < 6.1.189`\n- `Linux < 6.6.158`\n- `Linux < 6.12.111`\n- `Linux < 6.18.53`\n- `Linux (all versions)`\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":[]}