CVE-2022-48631

{"id": "CVE-2022-48631", "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": "2024-04-28T13:15:06.450", "references": [{"url": "https://git.kernel.org/stable/c/29a5b8a137ac8eb410cc823653a29ac0e7b7e1b0", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/2f5e9de15e4f55fbf56f22d4a2ce406246cc462d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/958b0ee23f5ac106e7cc11472b71aa2ea9a033bc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/bb7eb3ca4b3b0d2c7872cf1a41c30f5e5bd65df0", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/be4df018c0be5ebecf1ca510feacc23be415cefc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/29a5b8a137ac8eb410cc823653a29ac0e7b7e1b0", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/2f5e9de15e4f55fbf56f22d4a2ce406246cc462d", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/958b0ee23f5ac106e7cc11472b71aa2ea9a033bc", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/bb7eb3ca4b3b0d2c7872cf1a41c30f5e5bd65df0", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/be4df018c0be5ebecf1ca510feacc23be415cefc", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0\n\nWhen walking through an inode extents, the ext4_ext_binsearch_idx() function\nassumes that the extent header has been previously validated. However, there\nare no checks that verify that the number of entries (eh->eh_entries) is\nnon-zero when depth is > 0. And this will lead to problems because the\nEXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this:\n\n[ 135.245946] ------------[ cut here ]------------\n[ 135.247579] kernel BUG at fs/ext4/extents.c:2258!\n[ 135.249045] invalid opcode: 0000 [#1] PREEMPT SMP\n[ 135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4\n[ 135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014\n[ 135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0\n[ 135.256475] Code:\n[ 135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246\n[ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023\n[ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c\n[ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c\n[ 135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024\n[ 135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000\n[ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000\n[ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0\n[ 135.277952] Call Trace:\n[ 135.278635] <TASK>\n[ 135.279247] ? preempt_count_add+0x6d/0xa0\n[ 135.280358] ? percpu_counter_add_batch+0x55/0xb0\n[ 135.281612] ? _raw_read_unlock+0x18/0x30\n[ 135.282704] ext4_map_blocks+0x294/0x5a0\n[ 135.283745] ? xa_load+0x6f/0xa0\n[ 135.284562] ext4_mpage_readpages+0x3d6/0x770\n[ 135.285646] read_pages+0x67/0x1d0\n[ 135.286492] ? folio_add_lru+0x51/0x80\n[ 135.287441] page_cache_ra_unbounded+0x124/0x170\n[ 135.288510] filemap_get_pages+0x23d/0x5a0\n[ 135.289457] ? path_openat+0xa72/0xdd0\n[ 135.290332] filemap_read+0xbf/0x300\n[ 135.291158] ? _raw_spin_lock_irqsave+0x17/0x40\n[ 135.292192] new_sync_read+0x103/0x170\n[ 135.293014] vfs_read+0x15d/0x180\n[ 135.293745] ksys_read+0xa1/0xe0\n[ 135.294461] do_syscall_64+0x3c/0x80\n[ 135.295284] entry_SYSCALL_64_after_hwframe+0x46/0xb0\n\nThis patch simply adds an extra check in __ext4_ext_check(), verifying that\neh_entries is not 0 when eh_depth is > 0."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: corrige error en el an\u00e1lisis de extensiones cuando eh_entries == 0 y eh_ Depth &gt; 0 Al recorrer las extensiones de un inodo, la funci\u00f3n ext4_ext_binsearch_idx() asume que el encabezado de la extensi\u00f3n ha sido validado previamente. Sin embargo, no hay comprobaciones que verifiquen que el n\u00famero de entradas (eh-&gt;eh_entries) sea distinto de cero cuando la profundidad es &gt; 0. Y esto generar\u00e1 problemas porque EXT_FIRST_INDEX() y EXT_LAST_INDEX() devolver\u00e1n basura y dar\u00e1n como resultado esto: [135.245946] ------------[ cortar aqu\u00ed ]------------ [ 135.247579] \u00a1ERROR del kernel en fs/ext4/extents.c:2258! [ 135.249045] c\u00f3digo de operaci\u00f3n no v\u00e1lido: 0000 [#1] SMP PREEMPT [ 135.250320] CPU: 2 PID: 238 Comm: tmp118 No contaminado 5.19.0-rc8+ #4 [ 135.252067] Nombre de hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996) , BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 01/04/2014 [135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0 [135.256475] C\u00f3digo: [135.261433] RSP: ffffc900005939f8 EFLAGS: 00010246 [ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023 [ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000000 3 RDI: ffff8880046e922c [ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c [ 135.268576] R10: 00000000000002602 R 11: 0000000000000000 R12: 0000000000000024 [ 135.270477 ] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000 [ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) ) knlGS:0000000000000000 [ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 135.276075] CR2: 00007ffc26bd4f00 CR3 : 0000000006261004 CR4: 0000000000170ea0 [ 135.277952] Seguimiento de llamadas: [ 135.278635] [ 135.279247] ? preempt_count_add+0x6d/0xa0 [135.280358]? \u00bfpercpu_counter_add_batch+0x55/0xb0 [135.281612]? _raw_read_unlock+0x18/0x30 [ 135.282704] ext4_map_blocks+0x294/0x5a0 [ 135.283745] ? xa_load+0x6f/0xa0 [135.284562] ext4_mpage_readpages+0x3d6/0x770 [135.285646] read_pages+0x67/0x1d0 [135.286492] ? folio_add_lru+0x51/0x80 [ 135.287441] page_cache_ra_unbounded+0x124/0x170 [ 135.288510] filemap_get_pages+0x23d/0x5a0 [ 135.289457] ? path_openat+0xa72/0xdd0 [135.290332] filemap_read+0xbf/0x300 [135.291158]? _raw_spin_lock_irqsave+0x17/0x40 [ 135.292192] new_sync_read+0x103/0x170 [ 135.293014] vfs_read+0x15d/0x180 [ 135.293745] ksys_read+0xa1/0xe0 [ 135.294461] do_syscall_64+0x3c/0x80 [ 135.295284] Entry_SYSCALL_64_after_hwframe+0x46/0xb0 Este parche simplemente agrega un verificaci\u00f3n adicional en __ext4_ext_check(), verificando que eh_entries no sea 0 cuando eh_ Depth sea &gt; 0."}], "lastModified": "2025-09-19T14:56:13.800", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C1F13D37-AD51-4E30-9FD7-F6B539CE6CED", "versionEndExcluding": "5.4.215"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A9C1CF48-9C3A-4236-8546-BD32D742BFB7", "versionEndExcluding": "5.10.146", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "080C1827-D257-4D5A-9071-779EF7F5EF0B", "versionEndExcluding": "5.15.71", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "03B0F56B-C5CC-4E81-BB51-D07D569DE4CA", "versionEndExcluding": "5.19.12", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E8BD11A3-8643-49B6-BADE-5029A0117325"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5F0AD220-F6A9-4012-8636-155F1B841FAD"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A46498B3-78E1-4623-AAE1-94D29A42BE4E"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F8446E87-F5F6-41CA-8201-BAE0F0CA6DD9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8E5FB72F-67CE-43CC-83FE-541604D98182"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.0:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3A0A7397-F5F8-4753-82DC-9A11288E696D"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}