CVE-2026-98881
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net: bridge: remove stale rcu_barrier() in br_multicast_dev_del() This rcu_barrier() came from a time call_rcu() calls were used in net/bridge/br_multicast.c. Now kfree_rcu() is there, we can remove this problematic rcu_barrier() which causes extreme RTNL pressure in many syzbot reports. INFO: task syz-executor:77945 is blocked on a mutex likely owned by task kworker/u1024:5:36537. task:kworker/u1024:5 state:D stack:24616 pid:36537 tgid:36537 ppid:2 task_flags:0x4208060 flags:0x00080000 last_sleep:612797637337 Workqueue: netns cleanup_net Call Trace: <TASK> [<ffffffff81914eaa>] context_switch+0xf2a/0x1730 kernel/sched/core.c:6483 [<ffffffff81201143>] __schedule+0x1133/0x43a0 kernel/sched/core.c:8411 [<ffffffff8120446b>] __schedule_loop kernel/sched/core.c:8514 [inline] [<ffffffff8120446b>] schedule+0xab/0x260 kernel/sched/core.c:8529 [<ffffffff8121a093>] schedule_timeout+0xc3/0x2b0 kernel/time/sleep_timeout.c:75 [<ffffffff81205347>] do_wait_for_common kernel/sched/completion.c:100 [inline] [<ffffffff81205347>] __wait_for_common kernel/sched/completion.c:121 [inline] [<ffffffff81205347>] wait_for_common kernel/sched/completion.c:132 [inline] [<ffffffff81205347>] wait_for_completion+0x2c7/0x5d0 kernel/sched/completion.c:153 [<ffffffff81b8f27f>] rcu_barrier+0x49f/0x620 kernel/rcu/tree.c:3888 [<ffffffff860091b3>] br_multicast_dev_del+0x303/0x350 net/bridge/br_multicast.c:4459 [<ffffffff85fb5dbc>] br_dev_uninit+0x1c/0x40 net/bridge/br_device.c:157 [<ffffffff8568058c>] unregister_netdevice_many_notify+0x1c1c/0x2300 net/core/dev.c:12599 [<ffffffff8562be43>] ops_exit_rtnl_list net/core/net_namespace.c:187 [inline] [<ffffffff8562be43>] ops_undo_list+0x3d3/0x940 net/core/net_namespace.c:248
View original CVE JSON
{
"id": "CVE-2026-98881",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-10-23T12:18:21.670",
"lastModified": "2026-10-26T07:17:12.987",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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 <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"
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/bridge/br_multicast.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "35f9f11740515a10b084adfb1ce691351f2452ab",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "0443f6aac6bf6a91e406273fdda11497cef6ad07",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "ac0e823a228f94ad9d7a3d876cc07e59a7afb806",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "f0018acf0b66f93a292667c9a9c2a26c570cf270",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "372ee8fbe0f796031c60f676ec90f0788c26523d",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "39679927fa7aaf4601119f7234342d1b5d4f6f84",
"versionType": "git",
"status": "affected"
},
{
"version": "19e3a9c90c53479fecaa02307bf2db5ab8b3ffe3",
"lessThan": "25ae123db10ba9ab890b56bcdb0a4363aee8529a",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/bridge/br_multicast.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.0",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.0",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.271",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.222",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.189",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.158",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.111",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.53",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/0443f6aac6bf6a91e406273fdda11497cef6ad07",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/25ae123db10ba9ab890b56bcdb0a4363aee8529a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/35f9f11740515a10b084adfb1ce691351f2452ab",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/372ee8fbe0f796031c60f676ec90f0788c26523d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/39679927fa7aaf4601119f7234342d1b5d4f6f84",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ac0e823a228f94ad9d7a3d876cc07e59a7afb806",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f0018acf0b66f93a292667c9a9c2a26c570cf270",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}