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CVE-2021-47408 (GCVE-0-2021-47408)

Vulnerability from cvelistv5 – Published: 2024-05-21 15:04 – Updated: 2026-05-11 13:54
VLAI
Title
netfilter: conntrack: serialize hash resizes and cleanups
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: serialize hash resizes and cleanups Syzbot was able to trigger the following warning [1] No repro found by syzbot yet but I was able to trigger similar issue by having 2 scripts running in parallel, changing conntrack hash sizes, and: for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done It would take more than 5 minutes for net_namespace structures to be cleaned up. This is because nf_ct_iterate_cleanup() has to restart everytime a resize happened. By adding a mutex, we can serialize hash resizes and cleanups and also make get_next_corpse() faster by skipping over empty buckets. Even without resizes in the picture, this patch considerably speeds up network namespace dismantles. [1] INFO: task syz-executor.0:8312 can't die for more than 144 seconds. task:syz-executor.0 state:R running task stack:25672 pid: 8312 ppid: 6573 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline] nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 setup_net+0x639/0xa30 net/core/net_namespace.c:349 copy_net_ns+0x319/0x760 net/core/net_namespace.c:470 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3128 __do_sys_unshare kernel/fork.c:3202 [inline] __se_sys_unshare kernel/fork.c:3200 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f63da68e739 RSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80 R13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 2 locks held by kworker/u4:2/153: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268 #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272 1 lock held by systemd-udevd/2970: 1 lock held by in:imklog/6258: #0: ffff88807f970ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 3 locks held by kworker/1:6/8158: 1 lock held by syz-executor.0/8312: 2 locks held by kworker/u4:13/9320: 1 lock held by ---truncated---
Severity
4.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-29 18:07 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0d02d5646eb84403766a11a1d3b19e670a3d45d5 , < e2d192301a0df8160d1555b66ae8611e8050e424 (git)
Affected: 0d02d5646eb84403766a11a1d3b19e670a3d45d5 , < 7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1 (git)
Affected: 0d02d5646eb84403766a11a1d3b19e670a3d45d5 , < e9edc188fc76499b0b9bd60364084037f6d03773 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.13
Unaffected: 0 , < 4.13 (semver)
Unaffected: 5.10.71 , ≤ 5.10.* (semver)
Unaffected: 5.14.10 , ≤ 5.14.* (semver)
Unaffected: 5.15 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: serialize hash resizes and cleanups\n\nSyzbot was able to trigger the following warning [1]\n\nNo repro found by syzbot yet but I was able to trigger similar issue\nby having 2 scripts running in parallel, changing conntrack hash sizes,\nand:\n\nfor j in `seq 1 1000` ; do unshare -n /bin/true \u003e/dev/null ; done\n\nIt would take more than 5 minutes for net_namespace structures\nto be cleaned up.\n\nThis is because nf_ct_iterate_cleanup() has to restart everytime\na resize happened.\n\nBy adding a mutex, we can serialize hash resizes and cleanups\nand also make get_next_corpse() faster by skipping over empty\nbuckets.\n\nEven without resizes in the picture, this patch considerably\nspeeds up network namespace dismantles.\n\n[1]\nINFO: task syz-executor.0:8312 can\u0027t die for more than 144 seconds.\ntask:syz-executor.0  state:R  running task     stack:25672 pid: 8312 ppid:  6573 flags:0x00004006\nCall Trace:\n context_switch kernel/sched/core.c:4955 [inline]\n __schedule+0x940/0x26f0 kernel/sched/core.c:6236\n preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408\n preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35\n __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390\n local_bh_enable include/linux/bottom_half.h:32 [inline]\n get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]\n nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275\n nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469\n ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171\n setup_net+0x639/0xa30 net/core/net_namespace.c:349\n copy_net_ns+0x319/0x760 net/core/net_namespace.c:470\n create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110\n unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226\n ksys_unshare+0x445/0x920 kernel/fork.c:3128\n __do_sys_unshare kernel/fork.c:3202 [inline]\n __se_sys_unshare kernel/fork.c:3200 [inline]\n __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f63da68e739\nRSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110\nRAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000\nRBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80\nR13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000\n\nShowing all locks held in the system:\n1 lock held by khungtaskd/27:\n #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446\n2 locks held by kworker/u4:2/153:\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268\n #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272\n1 lock held by systemd-udevd/2970:\n1 lock held by in:imklog/6258:\n #0: ffff88807f970ff0 (\u0026f-\u003ef_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990\n3 locks held by kworker/1:6/8158:\n1 lock held by syz-executor.0/8312:\n2 locks held by kworker/u4:13/9320:\n1 lock held by\n---truncated---"
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      "title": "netfilter: conntrack: serialize hash resizes and cleanups",
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: serialize hash resizes and cleanups\n\nSyzbot was able to trigger the following warning [1]\n\nNo repro found by syzbot yet but I was able to trigger similar issue\nby having 2 scripts running in parallel, changing conntrack hash sizes,\nand:\n\nfor j in `seq 1 1000` ; do unshare -n /bin/true \u003e/dev/null ; done\n\nIt would take more than 5 minutes for net_namespace structures\nto be cleaned up.\n\nThis is because nf_ct_iterate_cleanup() has to restart everytime\na resize happened.\n\nBy adding a mutex, we can serialize hash resizes and cleanups\nand also make get_next_corpse() faster by skipping over empty\nbuckets.\n\nEven without resizes in the picture, this patch considerably\nspeeds up network namespace dismantles.\n\n[1]\nINFO: task syz-executor.0:8312 can\u0027t die for more than 144 seconds.\ntask:syz-executor.0  state:R  running task     stack:25672 pid: 8312 ppid:  6573 flags:0x00004006\nCall Trace:\n context_switch kernel/sched/core.c:4955 [inline]\n __schedule+0x940/0x26f0 kernel/sched/core.c:6236\n preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408\n preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35\n __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390\n local_bh_enable include/linux/bottom_half.h:32 [inline]\n get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]\n nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275\n nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469\n ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171\n setup_net+0x639/0xa30 net/core/net_namespace.c:349\n copy_net_ns+0x319/0x760 net/core/net_namespace.c:470\n create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110\n unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226\n ksys_unshare+0x445/0x920 kernel/fork.c:3128\n __do_sys_unshare kernel/fork.c:3202 [inline]\n __se_sys_unshare kernel/fork.c:3200 [inline]\n __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f63da68e739\nRSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110\nRAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000\nRBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80\nR13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000\n\nShowing all locks held in the system:\n1 lock held by khungtaskd/27:\n #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446\n2 locks held by kworker/u4:2/153:\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268\n #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272\n1 lock held by systemd-udevd/2970:\n1 lock held by in:imklog/6258:\n #0: ffff88807f970ff0 (\u0026f-\u003ef_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990\n3 locks held by kworker/1:6/8158:\n1 lock held by syz-executor.0/8312:\n2 locks held by kworker/u4:13/9320:\n1 lock held by\n---truncated---"
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        {
          "lang": "es",
          "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: netfilter: conntrack: serializar cambios de tama\u00f1o y limpiezas de hash. Syzbot pudo activar la siguiente advertencia [1] Syzbot a\u00fan no encontr\u00f3 ninguna reproducci\u00f3n, pero pude desencadenar un problema similar al tener 2 scripts ejecut\u00e1ndose en paralelo, cambiando los tama\u00f1os de hash de conntrack y: para j en `seq 1 1000`; dejar de compartir -n /bin/true \u0026gt;/dev/null ; done Se necesitar\u00edan m\u00e1s de 5 minutos para limpiar las estructuras net_namespace. Esto se debe a que nf_ct_iterate_cleanup() tiene que reiniciarse cada vez que ocurre un cambio de tama\u00f1o. Al agregar un mutex, podemos serializar los cambios de tama\u00f1o y las limpiezas de hash y tambi\u00e9n hacer que get_next_corpse() sea m\u00e1s r\u00e1pido omitiendo los dep\u00f3sitos vac\u00edos. Incluso sin cambios de tama\u00f1o en la imagen, este parche acelera considerablemente el desmantelamiento del espacio de nombres de la red. [1] INFORMACI\u00d3N: la tarea syz-executor.0:8312 no puede morir durante m\u00e1s de 144 segundos. tarea:syz-executor.0 estado:R ejecutando pila de tareas:25672 pid: 8312 ppid: 6573 banderas:0x00004006 Seguimiento de llamadas: context_switch kernel/sched/core.c:4955 [en l\u00ednea] __schedule+0x940/0x26f0 kernel/sched/core .c:6236 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390 local_bh_enable include/ Linux /bottom_half.h:32 [en l\u00ednea] get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [en l\u00ednea] nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/ nf_conntrack_core.c:2469 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 setup_net+0x639/0xa30 net/core/net_namespace.c:349 copy_net_ns+0x319/0x760 net/core/net_namespace.c:470 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy .c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3128 __do_sys_unshare kernel/fork.c:3202 [en l\u00ednea] __se_sys_unshare kernel/fork.c:3200 [en l\u00ednea] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200 do_syscall_x64 arch/x86/entry/common.c:50 [en l\u00ednea] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Entry_SYSCALL_64_after_hwframe+0x44/0xae : 0033:0x7f63da68e739 RSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 63da68e739 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80 R13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000 Mostrando todos los bloqueos retenidos en el sistema: 1 bloqueo retenido por khungtaskd/27: #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, : debug_show_all_locks+0x53 /0x260 kernel/locking/lockdep.c:6446 2 bloqueos retenidos por kworker/u4:2/153: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: arch_atomic64_set arch /x86/include/asm/atomic64_64.h:34 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: arch_atomic_long_set include/linux/atomic/atomic-long .h:41 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [en l\u00ednea] # 0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: set_work_data kernel/workqueue.c:634 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+. }-{0:0}, en: set_work_pool_and_clear_pending kernel/workqueue.c:661 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: Process_one_work+0x896/ 0x1690 kernel/workqueue.c:2268 #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, en: Process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272 1 bloqueo retenido por systemd-udevd/2970: 1 bloqueo retenido por in:imklog/6258: #0: ffff88807f970ff0 (\u0026amp;f-\u0026gt;f_pos_lock){+.+.}-{3:3}, en: __fdget_pos+0xe9/0x100 ---truncado---"
        }
      ],
      "id": "CVE-2021-47408",
      "lastModified": "2024-11-21T06:36:05.087",
      "metrics": {
        "cvssMetricV31": [
          {
            "cvssData": {
              "attackComplexity": "HIGH",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 4.7,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            },
            "exploitabilityScore": 1.0,
            "impactScore": 3.6,
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            "type": "Secondary"
          }
        ]
      },
      "published": "2024-05-21T15:15:26.337",
      "references": [
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "url": "https://git.kernel.org/stable/c/7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "url": "https://git.kernel.org/stable/c/e2d192301a0df8160d1555b66ae8611e8050e424"
        },
        {
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "url": "https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://git.kernel.org/stable/c/7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://git.kernel.org/stable/c/e2d192301a0df8160d1555b66ae8611e8050e424"
        },
        {
          "source": "af854a3a-2127-422b-91ae-364da2661108",
          "url": "https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773"
        }
      ],
      "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "vulnStatus": "Awaiting Analysis"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "net/netfilter/nf_conntrack_core.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "e2d192301a0df8160d1555b66ae8611e8050e424",
                    "status": "affected",
                    "version": "0d02d5646eb84403766a11a1d3b19e670a3d45d5",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "7ea6f5848281182ce0cff6cafdcf3fbdeb8ca7e1",
                    "status": "affected",
                    "version": "0d02d5646eb84403766a11a1d3b19e670a3d45d5",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "e9edc188fc76499b0b9bd60364084037f6d03773",
                    "status": "affected",
                    "version": "0d02d5646eb84403766a11a1d3b19e670a3d45d5",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/netfilter/nf_conntrack_core.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "4.13"
                  },
                  {
                    "lessThan": "4.13",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.71",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.14.*",
                    "status": "unaffected",
                    "version": "5.14.10",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "5.15",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "7A97507B-D1C6-49E3-9F7E-BFCDE3EA3905",
                    "versionEndExcluding": "5.10.71",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "1A437B0D-8305-4C72-B691-D26986A126CF",
                    "versionEndExcluding": "5.14.10",
                    "versionStartIncluding": "5.11",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "E46C74C6-B76B-4C94-A6A4-FD2FFF62D644",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "60134C3A-06E4-48C1-B04F-2903732A4E56",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "0460DA88-8FE1-46A2-9DDA-1F1ABA552E71",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: serialize hash resizes and cleanups\n\nSyzbot was able to trigger the following warning [1]\n\nNo repro found by syzbot yet but I was able to trigger similar issue\nby having 2 scripts running in parallel, changing conntrack hash sizes,\nand:\n\nfor j in `seq 1 1000` ; do unshare -n /bin/true \u003e/dev/null ; done\n\nIt would take more than 5 minutes for net_namespace structures\nto be cleaned up.\n\nThis is because nf_ct_iterate_cleanup() has to restart everytime\na resize happened.\n\nBy adding a mutex, we can serialize hash resizes and cleanups\nand also make get_next_corpse() faster by skipping over empty\nbuckets.\n\nEven without resizes in the picture, this patch considerably\nspeeds up network namespace dismantles.\n\n[1]\nINFO: task syz-executor.0:8312 can\u0027t die for more than 144 seconds.\ntask:syz-executor.0  state:R  running task     stack:25672 pid: 8312 ppid:  6573 flags:0x00004006\nCall Trace:\n context_switch kernel/sched/core.c:4955 [inline]\n __schedule+0x940/0x26f0 kernel/sched/core.c:6236\n preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408\n preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35\n __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390\n local_bh_enable include/linux/bottom_half.h:32 [inline]\n get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]\n nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275\n nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469\n ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171\n setup_net+0x639/0xa30 net/core/net_namespace.c:349\n copy_net_ns+0x319/0x760 net/core/net_namespace.c:470\n create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110\n unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226\n ksys_unshare+0x445/0x920 kernel/fork.c:3128\n __do_sys_unshare kernel/fork.c:3202 [inline]\n __se_sys_unshare kernel/fork.c:3200 [inline]\n __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f63da68e739\nRSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110\nRAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000\nRBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80\nR13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000\n\nShowing all locks held in the system:\n1 lock held by khungtaskd/27:\n #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446\n2 locks held by kworker/u4:2/153:\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268\n #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272\n1 lock held by systemd-udevd/2970:\n1 lock held by in:imklog/6258:\n #0: ffff88807f970ff0 (\u0026f-\u003ef_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990\n3 locks held by kworker/1:6/8158:\n1 lock held by syz-executor.0/8312:\n2 locks held by kworker/u4:13/9320:\n1 lock held by\n---truncated---"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: netfilter: conntrack: serializar cambios de tama\u00f1o y limpiezas de hash. Syzbot pudo activar la siguiente advertencia [1] Syzbot a\u00fan no encontr\u00f3 ninguna reproducci\u00f3n, pero pude desencadenar un problema similar al tener 2 scripts ejecut\u00e1ndose en paralelo, cambiando los tama\u00f1os de hash de conntrack y: para j en `seq 1 1000`; dejar de compartir -n /bin/true \u0026gt;/dev/null ; done Se necesitar\u00edan m\u00e1s de 5 minutos para limpiar las estructuras net_namespace. Esto se debe a que nf_ct_iterate_cleanup() tiene que reiniciarse cada vez que ocurre un cambio de tama\u00f1o. Al agregar un mutex, podemos serializar los cambios de tama\u00f1o y las limpiezas de hash y tambi\u00e9n hacer que get_next_corpse() sea m\u00e1s r\u00e1pido omitiendo los dep\u00f3sitos vac\u00edos. Incluso sin cambios de tama\u00f1o en la imagen, este parche acelera considerablemente el desmantelamiento del espacio de nombres de la red. [1] INFORMACI\u00d3N: la tarea syz-executor.0:8312 no puede morir durante m\u00e1s de 144 segundos. tarea:syz-executor.0 estado:R ejecutando pila de tareas:25672 pid: 8312 ppid: 6573 banderas:0x00004006 Seguimiento de llamadas: context_switch kernel/sched/core.c:4955 [en l\u00ednea] __schedule+0x940/0x26f0 kernel/sched/core .c:6236 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390 local_bh_enable include/ Linux /bottom_half.h:32 [en l\u00ednea] get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [en l\u00ednea] nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275 nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/ nf_conntrack_core.c:2469 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171 setup_net+0x639/0xa30 net/core/net_namespace.c:349 copy_net_ns+0x319/0x760 net/core/net_namespace.c:470 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy .c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3128 __do_sys_unshare kernel/fork.c:3202 [en l\u00ednea] __se_sys_unshare kernel/fork.c:3200 [en l\u00ednea] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200 do_syscall_x64 arch/x86/entry/common.c:50 [en l\u00ednea] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Entry_SYSCALL_64_after_hwframe+0x44/0xae : 0033:0x7f63da68e739 RSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 63da68e739 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80 R13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000 Mostrando todos los bloqueos retenidos en el sistema: 1 bloqueo retenido por khungtaskd/27: #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, : debug_show_all_locks+0x53 /0x260 kernel/locking/lockdep.c:6446 2 bloqueos retenidos por kworker/u4:2/153: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: arch_atomic64_set arch /x86/include/asm/atomic64_64.h:34 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: arch_atomic_long_set include/linux/atomic/atomic-long .h:41 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [en l\u00ednea] # 0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: set_work_data kernel/workqueue.c:634 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+. }-{0:0}, en: set_work_pool_and_clear_pending kernel/workqueue.c:661 [en l\u00ednea] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, en: Process_one_work+0x896/ 0x1690 kernel/workqueue.c:2268 #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, en: Process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272 1 bloqueo retenido por systemd-udevd/2970: 1 bloqueo retenido por in:imklog/6258: #0: ffff88807f970ff0 (\u0026amp;f-\u0026gt;f_pos_lock){+.+.}-{3:3}, en: __fdget_pos+0xe9/0x100 ---truncado---"
          }
        ],
        "id": "CVE-2021-47408",
        "lastModified": "2026-06-17T04:17:24.303",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            },
            {
              "cvssData": {
                "attackComplexity": "HIGH",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 4.7,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.0,
              "impactScore": 3.6,
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
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                "options": [
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                  {
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                ],
                "role": "CISA Coordinator",
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        "published": "2024-05-21T15:15:26.337",
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        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
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                "value": "NVD-CWE-noinfo"
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            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
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      "current_release_date": "2026-06-28T05:29:53+00:00",
      "cve": "CVE-2021-47408",
      "id": "CVE-2021-47408",
      "initial_release_date": "2021-01-01T00:00:00+00:00",
      "product_status:fixed": "150",
      "product_status:known_affected": "42",
      "product_status:known_not_affected": "108",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: netfilter: conntrack: serialize hash resizes and cleanups",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-47408.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T02:38:32Z",
      "cve": "CVE-2021-47408",
      "id": "CVE-2021-47408",
      "initial_release_date": "2024-05-25T03:34:29Z",
      "product_status:known_affected": "467",
      "product_status:known_not_affected": "77",
      "product_status:recommended": "484",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-47408",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-47408.json",
      "version": "63"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-04T05:39:59.320Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
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            "references": [
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                "url": "https://git.kernel.org/stable/c/e2d192301a0df8160d1555b66ae8611e8050e424"
              },
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                "url": "https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "cvssV3_1": {
                  "attackComplexity": "HIGH",
                  "attackVector": "LOCAL",
                  "availabilityImpact": "HIGH",
                  "baseScore": 4.7,
                  "baseSeverity": "MEDIUM",
                  "confidentialityImpact": "NONE",
                  "integrityImpact": "NONE",
                  "privilegesRequired": "LOW",
                  "scope": "UNCHANGED",
                  "userInteraction": "NONE",
                  "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "version": "3.1"
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              {
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            "problemTypes": [
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                    "lang": "en",
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              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
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            "title": "CISA ADP Vulnrichment"
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              "vendor": "Linux",
              "versions": [
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                  "status": "unaffected",
                  "version": "5.14.10",
                  "versionType": "semver"
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                {
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                  "status": "unaffected",
                  "version": "5.15",
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          "cpeApplicability": [
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                      "vulnerable": true
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          "descriptions": [
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              "lang": "en",
              "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: conntrack: serialize hash resizes and cleanups\n\nSyzbot was able to trigger the following warning [1]\n\nNo repro found by syzbot yet but I was able to trigger similar issue\nby having 2 scripts running in parallel, changing conntrack hash sizes,\nand:\n\nfor j in `seq 1 1000` ; do unshare -n /bin/true \u003e/dev/null ; done\n\nIt would take more than 5 minutes for net_namespace structures\nto be cleaned up.\n\nThis is because nf_ct_iterate_cleanup() has to restart everytime\na resize happened.\n\nBy adding a mutex, we can serialize hash resizes and cleanups\nand also make get_next_corpse() faster by skipping over empty\nbuckets.\n\nEven without resizes in the picture, this patch considerably\nspeeds up network namespace dismantles.\n\n[1]\nINFO: task syz-executor.0:8312 can\u0027t die for more than 144 seconds.\ntask:syz-executor.0  state:R  running task     stack:25672 pid: 8312 ppid:  6573 flags:0x00004006\nCall Trace:\n context_switch kernel/sched/core.c:4955 [inline]\n __schedule+0x940/0x26f0 kernel/sched/core.c:6236\n preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408\n preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35\n __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390\n local_bh_enable include/linux/bottom_half.h:32 [inline]\n get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]\n nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275\n nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469\n ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171\n setup_net+0x639/0xa30 net/core/net_namespace.c:349\n copy_net_ns+0x319/0x760 net/core/net_namespace.c:470\n create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110\n unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226\n ksys_unshare+0x445/0x920 kernel/fork.c:3128\n __do_sys_unshare kernel/fork.c:3202 [inline]\n __se_sys_unshare kernel/fork.c:3200 [inline]\n __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f63da68e739\nRSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110\nRAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000\nRBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80\nR13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000\n\nShowing all locks held in the system:\n1 lock held by khungtaskd/27:\n #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446\n2 locks held by kworker/u4:2/153:\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]\n #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268\n #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272\n1 lock held by systemd-udevd/2970:\n1 lock held by in:imklog/6258:\n #0: ffff88807f970ff0 (\u0026f-\u003ef_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990\n3 locks held by kworker/1:6/8158:\n1 lock held by syz-executor.0/8312:\n2 locks held by kworker/u4:13/9320:\n1 lock held by\n---truncated---"
            }
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            "dateUpdated": "2025-12-18T11:37:27.872Z",
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              "url": "https://git.kernel.org/stable/c/e9edc188fc76499b0b9bd60364084037f6d03773"
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          "title": "netfilter: conntrack: serialize hash resizes and cleanups",
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      "cveMetadata": {
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        "datePublished": "2024-05-21T15:04:00.651Z",
        "dateReserved": "2024-05-21T14:58:30.817Z",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.