CVE-2022-48914

{"id": "CVE-2022-48914", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-08-22T02:15:05.683", "references": [{"url": "https://git.kernel.org/stable/c/198cdc287769c717dafff5887c6125cb7a373bf3", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/47e2f166ed9fe17f24561d6315be2228f6a90209", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a1753d5c29a6fb9a8966dcf04cb4f3b71e303ae8", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a63eb1e4a2e1a191a90217871e67fba42fd39255", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b40c912624775a21da32d1105e158db5f6d0554a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/dcf4ff7a48e7598e6b10126cc02177abb8ae4f3f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxen/netfront: destroy queues before real_num_tx_queues is zeroed\n\nxennet_destroy_queues() relies on info->netdev->real_num_tx_queues to\ndelete queues. Since d7dac083414eb5bb99a6d2ed53dc2c1b405224e5\n(\"net-sysfs: update the queue counts in the unregistration path\"),\nunregister_netdev() indirectly sets real_num_tx_queues to 0. Those two\nfacts together means, that xennet_destroy_queues() called from\nxennet_remove() cannot do its job, because it's called after\nunregister_netdev(). This results in kfree-ing queues that are still\nlinked in napi, which ultimately crashes:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 0 P4D 0\n Oops: 0000 [#1] PREEMPT SMP PTI\n CPU: 1 PID: 52 Comm: xenwatch Tainted: G W 5.16.10-1.32.fc32.qubes.x86_64+ #226\n RIP: 0010:free_netdev+0xa3/0x1a0\n Code: ff 48 89 df e8 2e e9 00 00 48 8b 43 50 48 8b 08 48 8d b8 a0 fe ff ff 48 8d a9 a0 fe ff ff 49 39 c4 75 26 eb 47 e8 ed c1 66 ff <48> 8b 85 60 01 00 00 48 8d 95 60 01 00 00 48 89 ef 48 2d 60 01 00\n RSP: 0000:ffffc90000bcfd00 EFLAGS: 00010286\n RAX: 0000000000000000 RBX: ffff88800edad000 RCX: 0000000000000000\n RDX: 0000000000000001 RSI: ffffc90000bcfc30 RDI: 00000000ffffffff\n RBP: fffffffffffffea0 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800edad050\n R13: ffff8880065f8f88 R14: 0000000000000000 R15: ffff8880066c6680\n FS: 0000000000000000(0000) GS:ffff8880f3300000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 0000000000000000 CR3: 00000000e998c006 CR4: 00000000003706e0\n Call Trace:\n <TASK>\n xennet_remove+0x13d/0x300 [xen_netfront]\n xenbus_dev_remove+0x6d/0xf0\n __device_release_driver+0x17a/0x240\n device_release_driver+0x24/0x30\n bus_remove_device+0xd8/0x140\n device_del+0x18b/0x410\n ? _raw_spin_unlock+0x16/0x30\n ? klist_iter_exit+0x14/0x20\n ? xenbus_dev_request_and_reply+0x80/0x80\n device_unregister+0x13/0x60\n xenbus_dev_changed+0x18e/0x1f0\n xenwatch_thread+0xc0/0x1a0\n ? do_wait_intr_irq+0xa0/0xa0\n kthread+0x16b/0x190\n ? set_kthread_struct+0x40/0x40\n ret_from_fork+0x22/0x30\n </TASK>\n\nFix this by calling xennet_destroy_queues() from xennet_uninit(),\nwhen real_num_tx_queues is still available. This ensures that queues are\ndestroyed when real_num_tx_queues is set to 0, regardless of how\nunregister_netdev() was called.\n\nOriginally reported at\nhttps://github.com/QubesOS/qubes-issues/issues/7257"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: xen/netfront: destruye colas antes de que real_num_tx_queues se ponga a cero xennet_destroy_queues() se basa en info-&gt;netdev-&gt;real_num_tx_queues para eliminar colas. Dado que d7dac083414eb5bb99a6d2ed53dc2c1b405224e5 (\"net-sysfs: actualice los recuentos de colas en la ruta de cancelaci\u00f3n de registro\"), unregister_netdev() establece indirectamente real_num_tx_queues en 0. Esos dos hechos juntos significan que xennet_destroy_queues() llamado desde xennet_remove() no puede hacer su trabajo, porque s llamado despu\u00e9s de unregister_netdev(). Esto da como resultado colas kfree-ing que todav\u00eda est\u00e1n vinculadas en napi, lo que finalmente falla: ERROR: desreferencia del puntero NULL del kernel, direcci\u00f3n: 0000000000000000 #PF: acceso de lectura del supervisor en modo kernel #PF: c\u00f3digo_error(0x0000) - PGD de p\u00e1gina no presente 0 P4D 0 Ups: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 52 Comm: xenwatch Tainted: GW 5.16.10-1.32.fc32.qubes.x86_64+ #226 RIP: 0010:free_netdev+0xa3/0x1a0 C\u00f3digo: ff 48 89 df e8 2e e9 00 00 48 8b 43 50 48 8b 08 48 8d b8 a0 fe ff ff 48 8d a9 a0 fe ff ff 49 39 c4 75 26 eb 47 e8 ed c1 66 ff &lt;48&gt; 8b 85 60 01 00 0 48 8d 95 60 01 00 00 48 89 ef 48 2d 60 01 00 RSP: 0000:ffffc90000bcfd00 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88800edad000 RCX: 0000000000000 RDX: 0000000000000001 RSI: ffffc90000bcfc30 RDI: 00000000ffffffff RBP: fffffffffffffea0 R08: 00000000000000000 R09: 00000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800edad050 R13: ffff8880065f8f88 R14: 00000000000000000 R15: ffff8880066c6680 FS: 00000000000000(0000) GS:ffff8880f3300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: CR3: 00000000e998c006 CR4: 00000000003706e0 Seguimiento de llamadas: xennet_remove+0x13d/0x300 [xen_netfront] xenbus_dev_remove+0x6d/0xf0 __device_release_driver+0x17a/0x240 device_release_driver+0x24/ 0x30 bus_remove_device+0xd8/0x140 dispositivo_del+0x18b/0x410? _raw_spin_unlock+0x16/0x30? klist_iter_exit+0x14/0x20? xenbus_dev_request_and_reply+0x80/0x80 dispositivo_unregister+0x13/0x60 xenbus_dev_changed+0x18e/0x1f0 xenwatch_thread+0xc0/0x1a0 ? do_wait_intr_irq+0xa0/0xa0 kthread+0x16b/0x190 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x22/0x30 Solucione este problema llamando a xennet_destroy_queues() desde xennet_uninit(), cuando real_num_tx_queues todav\u00eda est\u00e9 disponible. Esto garantiza que las colas se destruyan cuando real_num_tx_queues se establece en 0, independientemente de c\u00f3mo se llam\u00f3 a unregister_netdev(). Reportado originalmente en https://github.com/QubesOS/qubes-issues/issues/7257"}], "lastModified": "2024-09-12T13:27:34.623", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "844F8286-579D-45F3-91F9-B0963A45C46A", "versionEndExcluding": "4.19.233", "versionStartIncluding": "4.19.226"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "50DC6A9D-EDB7-4237-9253-6A36CB2A79E7", "versionEndExcluding": "5.4.183", "versionStartIncluding": "5.4.174"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "07144469-6081-4ABC-AD38-F23A8D9B3E86", "versionEndExcluding": "5.10.104", "versionStartIncluding": "5.10.94"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A3C6A607-7094-4C3C-B703-C6B5A1F87670", "versionEndExcluding": "5.15.27", "versionStartIncluding": "5.15.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CA1CE57C-E9AE-4BFC-8E39-AECD1A63C9A0", "versionEndExcluding": "5.16.13", "versionStartIncluding": "5.16.3"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}