{"id":"CVE-2026-98881","summary":"net: bridge: remove stale rcu_barrier() in br_multicast_dev_del()","details":"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 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 \u003cTASK\u003e\n  [\u003cffffffff81914eaa\u003e] context_switch+0xf2a/0x1730 kernel/sched/core.c:6483\n  [\u003cffffffff81201143\u003e] __schedule+0x1133/0x43a0 kernel/sched/core.c:8411\n  [\u003cffffffff8120446b\u003e] __schedule_loop kernel/sched/core.c:8514 [inline]\n  [\u003cffffffff8120446b\u003e] schedule+0xab/0x260 kernel/sched/core.c:8529\n  [\u003cffffffff8121a093\u003e] schedule_timeout+0xc3/0x2b0 kernel/time/sleep_timeout.c:75\n  [\u003cffffffff81205347\u003e] do_wait_for_common kernel/sched/completion.c:100 [inline]\n  [\u003cffffffff81205347\u003e] __wait_for_common kernel/sched/completion.c:121 [inline]\n  [\u003cffffffff81205347\u003e] wait_for_common kernel/sched/completion.c:132 [inline]\n  [\u003cffffffff81205347\u003e] wait_for_completion+0x2c7/0x5d0 kernel/sched/completion.c:153\n  [\u003cffffffff81b8f27f\u003e] rcu_barrier+0x49f/0x620 kernel/rcu/tree.c:3888\n  [\u003cffffffff860091b3\u003e] br_multicast_dev_del+0x303/0x350 net/bridge/br_multicast.c:4459\n  [\u003cffffffff85fb5dbc\u003e] br_dev_uninit+0x1c/0x40 net/bridge/br_device.c:157\n  [\u003cffffffff8568058c\u003e] unregister_netdevice_many_notify+0x1c1c/0x2300 net/core/dev.c:12599\n  [\u003cffffffff8562be43\u003e] ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]\n  [\u003cffffffff8562be43\u003e] ops_undo_list+0x3d3/0x940 net/core/net_namespace.c:248","modified":"2026-10-28T02:36:34.571706328Z","published":"2026-10-23T11:37:32.327Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98881.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0443f6aac6bf6a91e406273fdda11497cef6ad07"},{"type":"WEB","url":"https://git.kernel.org/stable/c/25ae123db10ba9ab890b56bcdb0a4363aee8529a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/35f9f11740515a10b084adfb1ce691351f2452ab"},{"type":"WEB","url":"https://git.kernel.org/stable/c/372ee8fbe0f796031c60f676ec90f0788c26523d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/39679927fa7aaf4601119f7234342d1b5d4f6f84"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ac0e823a228f94ad9d7a3d876cc07e59a7afb806"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f0018acf0b66f93a292667c9a9c2a26c570cf270"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98881.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98881"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3"},{"fixed":"35f9f11740515a10b084adfb1ce691351f2452ab"},{"fixed":"0443f6aac6bf6a91e406273fdda11497cef6ad07"},{"fixed":"ac0e823a228f94ad9d7a3d876cc07e59a7afb806"},{"fixed":"f0018acf0b66f93a292667c9a9c2a26c570cf270"},{"fixed":"372ee8fbe0f796031c60f676ec90f0788c26523d"},{"fixed":"39679927fa7aaf4601119f7234342d1b5d4f6f84"},{"fixed":"25ae123db10ba9ab890b56bcdb0a4363aee8529a"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-98881.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"5.10.271"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.222"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.189"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.158"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.111"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.53"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-98881.json"}}],"schema_version":"1.9.2"}