CVE-2021-47222

{"id": "CVE-2021-47222", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2024-05-21T15:15:11.453", "references": [{"url": "https://git.kernel.org/stable/c/25053a8404ba17ca48f5553d487afc1882e9f56c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/42020f7f37a90d24b9551f5f7eba3f7c7c102968", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/79855be6445b6592bddb7bd7167083ec8cdbd73f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cfc579f9d89af4ada58c69b03bcaa4887840f3b3", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/25053a8404ba17ca48f5553d487afc1882e9f56c", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/42020f7f37a90d24b9551f5f7eba3f7c7c102968", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/79855be6445b6592bddb7bd7167083ec8cdbd73f", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/cfc579f9d89af4ada58c69b03bcaa4887840f3b3", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: fix vlan tunnel dst refcnt when egressing\n\nThe egress tunnel code uses dst_clone() and directly sets the result\nwhich is wrong because the entry might have 0 refcnt or be already deleted,\ncausing number of problems. It also triggers the WARN_ON() in dst_hold()[1]\nwhen a refcnt couldn't be taken. Fix it by using dst_hold_safe() and\nchecking if a reference was actually taken before setting the dst.\n\n[1] dmesg WARN_ON log and following refcnt errors\n WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]\n Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net\n CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G W 5.13.0-rc3+ #360\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014\n RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]\n Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49\n RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246\n RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0\n RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001\n R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000\n R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401\n FS: 0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0\n Call Trace:\n br_handle_vlan+0xbc/0xca [bridge]\n __br_forward+0x23/0x164 [bridge]\n deliver_clone+0x41/0x48 [bridge]\n br_handle_frame_finish+0x36f/0x3aa [bridge]\n ? skb_dst+0x2e/0x38 [bridge]\n ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge]\n ? br_handle_frame_finish+0x3aa/0x3aa [bridge]\n br_handle_frame+0x2c3/0x377 [bridge]\n ? __skb_pull+0x33/0x51\n ? vlan_do_receive+0x4f/0x36a\n ? br_handle_frame_finish+0x3aa/0x3aa [bridge]\n __netif_receive_skb_core+0x539/0x7c6\n ? __list_del_entry_valid+0x16e/0x1c2\n __netif_receive_skb_list_core+0x6d/0xd6\n netif_receive_skb_list_internal+0x1d9/0x1fa\n gro_normal_list+0x22/0x3e\n dev_gro_receive+0x55b/0x600\n ? detach_buf_split+0x58/0x140\n napi_gro_receive+0x94/0x12e\n virtnet_poll+0x15d/0x315 [virtio_net]\n __napi_poll+0x2c/0x1c9\n net_rx_action+0xe6/0x1fb\n __do_softirq+0x115/0x2d8\n run_ksoftirqd+0x18/0x20\n smpboot_thread_fn+0x183/0x19c\n ? smpboot_unregister_percpu_thread+0x66/0x66\n kthread+0x10a/0x10f\n ? kthread_mod_delayed_work+0xb6/0xb6\n ret_from_fork+0x22/0x30\n ---[ end trace 49f61b07f775fd2b ]---\n dst_release: dst:00000000c02d677a refcnt:-1\n dst_release underflow"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: bridge: corrige el refcnt dst del t\u00fanel vlan al salir El c\u00f3digo del t\u00fanel de salida usa dst_clone() y establece directamente el resultado que es incorrecto porque la entrada puede tener 0 refcnt o ya estar eliminada , causando varios problemas. Tambi\u00e9n activa WARN_ON() en dst_hold()[1] cuando no se puede tomar una referencia. Solucionelo usando dst_hold_safe() y verificando si realmente se tom\u00f3 una referencia antes de configurar el dst. [1] Registro dmesg WARN_ON y siguientes errores de referencia ADVERTENCIA: CPU: 5 PID: 38 en include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [puente] M\u00f3dulos vinculados en: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net CPU : 5 PID: 38 Comm: ksoftirqd/5 Kdump: cargado Contaminado: GW 5.13.0-rc3+ #360 Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 01/04/2014 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [puente] C\u00f3digo: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 f6 e8 64 a.C. 01 e1 85 db 75 02 &lt;0f&gt; 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49 RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246 RAX: 00000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0 RBP: ffff8881040c6700 R08: 0000000000000000 R09: 00000000000000001 R10: 2ce93d0054fe0d00 R11: d00000e0000 R12: ffff888109515000 R13: 0000000000000000 R14: 0000000000000001 R15: 00000000000000401 FS: 0000000000000000(0000) 8822bf40000(0000) knlGS:0000000000000000CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0 Seguimiento de llamadas: br_handle_vlan+0xbc/0xca [puente] _forward+0x23/0x164 [puente] delivery_clone+0x41/0x48 [puente] br_handle_frame_finish+0x36f/ 0x3aa [puente] ? skb_dst+0x2e/0x38 [puente]? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [puente]? br_handle_frame_finish+0x3aa/0x3aa [puente] br_handle_frame+0x2c3/0x377 [puente]? __skb_pull+0x33/0x51? vlan_do_receive+0x4f/0x36a? br_handle_frame_finish+0x3aa/0x3aa [puente] __netif_receive_skb_core+0x539/0x7c6? __list_del_entry_valid+0x16e/0x1c2 __netif_receive_skb_list_core+0x6d/0xd6 netif_receive_skb_list_internal+0x1d9/0x1fa gro_normal_list+0x22/0x3e dev_gro_receive+0x55b/0x600 ? detach_buf_split+0x58/0x140 napi_gro_receive+0x94/0x12e virtnet_poll+0x15d/0x315 [virtio_net] __napi_poll+0x2c/0x1c9 net_rx_action+0xe6/0x1fb __do_softirq+0x115/0x2d8 run_ksoftirq d+0x18/0x20 smpboot_thread_fn+0x183/0x19c ? smpboot_unregister_percpu_thread+0x66/0x66 kthread+0x10a/0x10f? kthread_mod_delayed_work+0xb6/0xb6 ret_from_fork+0x22/0x30 ---[ end trace 49f61b07f775fd2b ]--- dst_release: dst:00000000c02d677a refcnt:-1 dst_release underflow"}], "lastModified": "2025-04-29T19:13:04.043", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "32B54D58-21AF-4B0B-B388-EADE824369F7", "versionEndExcluding": "4.14.238", "versionStartIncluding": "4.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F3CAB837-7D38-4934-AD4F-195CEFD754E6", "versionEndExcluding": "4.19.196", "versionStartIncluding": "4.15"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6267BD4E-BE25-48B5-B850-4B493440DAFA", "versionEndExcluding": "5.4.128", "versionStartIncluding": "4.20"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "59455D13-A902-42E1-97F7-5ED579777193", "versionEndExcluding": "5.10.46", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7806E7E5-6D4F-4E18-81C1-79B3C60EE855", "versionEndExcluding": "5.12.13", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "96AC23B2-D46A-49D9-8203-8E1BEDCA8532"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DA610E30-717C-4700-9F77-A3C9244F3BFD"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1ECD33F5-85BE-430B-8F86-8D7BD560311D"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CF351855-2437-4CF5-AD7C-BDFA51F27683"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "25A855BA-2118-44F2-90EF-EBBB12AF51EF"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}