CVE-2025-21884

{"id": "CVE-2025-21884", "cveTags": [], "metrics": {}, "published": "2025-03-27T15:15:56.313", "references": [{"url": "https://git.kernel.org/stable/c/4ceb0bd4ffd009821b585ce6a8033b12b59fb5fb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/5c70eb5c593d64d93b178905da215a9fd288a4b5", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c31a732fac46b00b95b78fcc9c37cb48dd6f2e0c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Awaiting Analysis", "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: better track kernel sockets lifetime\n\nWhile kernel sockets are dismantled during pernet_operations->exit(),\ntheir freeing can be delayed by any tx packets still held in qdisc\nor device queues, due to skb_set_owner_w() prior calls.\n\nThis then trigger the following warning from ref_tracker_dir_exit() [1]\n\nTo fix this, make sure that kernel sockets own a reference on net->passive.\n\nAdd sk_net_refcnt_upgrade() helper, used whenever a kernel socket\nis converted to a refcounted one.\n\n[1]\n\n[ 136.263918][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at\n[ 136.263918][ T35] sk_alloc+0x2b3/0x370\n[ 136.263918][ T35] inet6_create+0x6ce/0x10f0\n[ 136.263918][ T35] __sock_create+0x4c0/0xa30\n[ 136.263918][ T35] inet_ctl_sock_create+0xc2/0x250\n[ 136.263918][ T35] igmp6_net_init+0x39/0x390\n[ 136.263918][ T35] ops_init+0x31e/0x590\n[ 136.263918][ T35] setup_net+0x287/0x9e0\n[ 136.263918][ T35] copy_net_ns+0x33f/0x570\n[ 136.263918][ T35] create_new_namespaces+0x425/0x7b0\n[ 136.263918][ T35] unshare_nsproxy_namespaces+0x124/0x180\n[ 136.263918][ T35] ksys_unshare+0x57d/0xa70\n[ 136.263918][ T35] __x64_sys_unshare+0x38/0x40\n[ 136.263918][ T35] do_syscall_64+0xf3/0x230\n[ 136.263918][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[ 136.263918][ T35]\n[ 136.343488][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at\n[ 136.343488][ T35] sk_alloc+0x2b3/0x370\n[ 136.343488][ T35] inet6_create+0x6ce/0x10f0\n[ 136.343488][ T35] __sock_create+0x4c0/0xa30\n[ 136.343488][ T35] inet_ctl_sock_create+0xc2/0x250\n[ 136.343488][ T35] ndisc_net_init+0xa7/0x2b0\n[ 136.343488][ T35] ops_init+0x31e/0x590\n[ 136.343488][ T35] setup_net+0x287/0x9e0\n[ 136.343488][ T35] copy_net_ns+0x33f/0x570\n[ 136.343488][ T35] create_new_namespaces+0x425/0x7b0\n[ 136.343488][ T35] unshare_nsproxy_namespaces+0x124/0x180\n[ 136.343488][ T35] ksys_unshare+0x57d/0xa70\n[ 136.343488][ T35] __x64_sys_unshare+0x38/0x40\n[ 136.343488][ T35] do_syscall_64+0xf3/0x230\n[ 136.343488][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: mejorar el seguimiento del ciclo de vida de los sockets del kernel. Mientras los sockets del kernel se desmantelan durante pernet_operations->exit(), su liberaci\u00f3n puede verse retrasada por cualquier paquete de transmisi\u00f3n que a\u00fan se encuentre en la qdisc o en las colas de dispositivos, debido a llamadas previas a skb_set_owner_w(). Esto genera la siguiente advertencia de ref_tracker_dir_exit() [1]. Para solucionar esto, aseg\u00farese de que los sockets del kernel posean una referencia en net->passive. Agregue el asistente sk_net_refcnt_upgrade(), que se utiliza siempre que un socket del kernel se convierte a uno con recuento de referencia. [1] [ 136.263918][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.263918][ T35] sk_alloc+0x2b3/0x370 [ 136.263918][ T35] inet6_create+0x6ce/0x10f0 [ 136.263918][ T35] __sock_create+0x4c0/0xa30 [ 136.263918][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.263918][ T35] igmp6_net_init+0x39/0x390 [ 136.263918][ T35] ops_init+0x31e/0x590 [ 136.263918][ T35] setup_net+0x287/0x9e0 [ 136.263918][ T35] copy_net_ns+0x33f/0x570 [ 136.263918][ T35] create_new_namespaces+0x425/0x7b0 [ 136.263918][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.263918][ T35] ksys_unshare+0x57d/0xa70 [ 136.263918][ T35] __x64_sys_unshare+0x38/0x40 [ 136.263918][ T35] do_syscall_64+0xf3/0x230 [ 136.263918][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 136.263918][ T35] [ 136.343488][ T35] ref_tracker: net notrefcnt@ffff8880638f01e0 has 1/2 users at [ 136.343488][ T35] sk_alloc+0x2b3/0x370 [ 136.343488][ T35] inet6_create+0x6ce/0x10f0 [ 136.343488][ T35] __sock_create+0x4c0/0xa30 [ 136.343488][ T35] inet_ctl_sock_create+0xc2/0x250 [ 136.343488][ T35] ndisc_net_init+0xa7/0x2b0 [ 136.343488][ T35] ops_init+0x31e/0x590 [ 136.343488][ T35] setup_net+0x287/0x9e0 [ 136.343488][ T35] copy_net_ns+0x33f/0x570 [ 136.343488][ T35] create_new_namespaces+0x425/0x7b0 [ 136.343488][ T35] unshare_nsproxy_namespaces+0x124/0x180 [ 136.343488][ T35] ksys_unshare+0x57d/0xa70 [ 136.343488][ T35] __x64_sys_unshare+0x38/0x40 [ 136.343488][ T35] do_syscall_64+0xf3/0x230 [ 136.343488][ T35] entry_SYSCALL_64_after_hwframe+0x77/0x7f"}], "lastModified": "2025-08-20T18:15:31.680", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}