CVE-2021-47242

{"id": "CVE-2021-47242", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2024-05-21T15:15:13.327", "references": [{"url": "https://git.kernel.org/stable/c/27ef25c72373222aaa5fe7b5cd890ae9cfb89a8d", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/499ada5073361c631f2a3c4a8aed44d53b6f82ec", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-667"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix soft lookup in subflow_error_report()\n\nMaxim reported a soft lookup in subflow_error_report():\n\n watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:0]\n RIP: 0010:native_queued_spin_lock_slowpath\n RSP: 0018:ffffa859c0003bc0 EFLAGS: 00000202\n RAX: 0000000000000101 RBX: 0000000000000001 RCX: 0000000000000000\n RDX: ffff9195c2772d88 RSI: 0000000000000000 RDI: ffff9195c2772d88\n RBP: ffff9195c2772d00 R08: 00000000000067b0 R09: c6e31da9eb1e44f4\n R10: ffff9195ef379700 R11: ffff9195edb50710 R12: ffff9195c2772d88\n R13: ffff9195f500e3d0 R14: ffff9195ef379700 R15: ffff9195ef379700\n FS: 0000000000000000(0000) GS:ffff91961f400000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000c000407000 CR3: 0000000002988000 CR4: 00000000000006f0\n Call Trace:\n <IRQ>\n _raw_spin_lock_bh\n subflow_error_report\n mptcp_subflow_data_available\n __mptcp_move_skbs_from_subflow\n mptcp_data_ready\n tcp_data_queue\n tcp_rcv_established\n tcp_v4_do_rcv\n tcp_v4_rcv\n ip_protocol_deliver_rcu\n ip_local_deliver_finish\n __netif_receive_skb_one_core\n netif_receive_skb\n rtl8139_poll 8139too\n __napi_poll\n net_rx_action\n __do_softirq\n __irq_exit_rcu\n common_interrupt\n </IRQ>\n\nThe calling function - mptcp_subflow_data_available() - can be invoked\nfrom different contexts:\n- plain ssk socket lock\n- ssk socket lock + mptcp_data_lock\n- ssk socket lock + mptcp_data_lock + msk socket lock.\n\nSince subflow_error_report() tries to acquire the mptcp_data_lock, the\nlatter two call chains will cause soft lookup.\n\nThis change addresses the issue moving the error reporting call to\nouter functions, where the held locks list is known and the we can\nacquire only the needed one."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: mptcp: corrige una b\u00fasqueda suave en subflow_error_report(). Maxim inform\u00f3 una b\u00fasqueda suave en subflow_error_report(): vigilancia: ERROR: bloqueo suave - \u00a1CPU#0 bloqueada durante 22 segundos! [swapper/0:0] RIP: 0010:native_queued_spin_lock_slowpath RSP: 0018:ffffa859c0003bc0 EFLAGS: 00000202 RAX: 0000000000000101 RBX: 0000000000000001 RCX: 000000000 0000000 RDX: ffff9195c2772d88 RSI: 0000000000000000 RDI: ffff9195c2772d88 RBP: ffff9195c2772d00 R08: 00000000000067b0 R09: c6e31da9eb1e44f4 :ffff9195ef379700 R11: ffff9195edb50710 R12: ffff9195c2772d88 R13: ffff9195f500e3d0 R14: ffff9195ef379700 R15: ffff9195ef379700 FS: 0000000000000000(0000) 1961f400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c000407000 CR3: 0000000002988000 00000000000006f0 Seguimiento de llamadas: _raw_spin_lock_bh subflow_error_report mptcp_subflow_data_available __mptcp_move_skbs_from_subflow mptcp_data_ready tcp_data_queue tcp_rcv_establecido tcp_v4_do_rcv tcp_v4_rcv liver_rcu ip_local_deliver_finish __netif_receive_skb_one_core netif_receive_skb rtl8139_poll 8139too __napi_poll net_rx_action __do_softirq __irq_exit_rcu common_interrupt La funci\u00f3n de llamada, mptcp_subflow_data_available(), se puede invocar desde diferentes contextos: - enchufe ssk lock - bloqueo de socket ssk + mptcp_data_lock - bloqueo de socket ssk + mptcp_data_lock + bloqueo de socket msk. Dado que subflow_error_report() intenta adquirir mptcp_data_lock, las dos \u00faltimas cadenas de llamadas provocar\u00e1n una b\u00fasqueda suave. Este cambio soluciona el problema de mover la llamada de informe de errores a funciones externas, donde se conoce la lista de bloqueos retenidos y solo podemos adquirir el que necesitamos."}], "lastModified": "2024-07-08T14:16:16.353", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}