CVE-2022-49068

{"id": "CVE-2022-49068", "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": "2025-02-26T07:00:44.027", "references": [{"url": "https://git.kernel.org/stable/c/07cacfd9d9dc134557ac8866c73d570a59b3d1f3", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/6d82ad13c4110e73c7b0392f00534a1502a1b520", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a04d37ddfe4be431b9e52e8504490376ab0a39a4", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "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\nbtrfs: release correct delalloc amount in direct IO write path\n\nRunning generic/406 causes the following WARNING in btrfs_destroy_inode()\nwhich tells there are outstanding extents left.\n\nIn btrfs_get_blocks_direct_write(), we reserve a temporary outstanding\nextents with btrfs_delalloc_reserve_metadata() (or indirectly from\nbtrfs_delalloc_reserve_space(()). We then release the outstanding extents\nwith btrfs_delalloc_release_extents(). However, the \"len\" can be modified\nin the COW case, which releases fewer outstanding extents than expected.\n\nFix it by calling btrfs_delalloc_release_extents() for the original length.\n\nTo reproduce the warning, the filesystem should be 1 GiB. It's\ntriggering a short-write, due to not being able to allocate a large\nextent and instead allocating a smaller one.\n\n WARNING: CPU: 0 PID: 757 at fs/btrfs/inode.c:8848 btrfs_destroy_inode+0x1e6/0x210 [btrfs]\n Modules linked in: btrfs blake2b_generic xor lzo_compress\n lzo_decompress raid6_pq zstd zstd_decompress zstd_compress xxhash zram\n zsmalloc\n CPU: 0 PID: 757 Comm: umount Not tainted 5.17.0-rc8+ #101\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS d55cb5a 04/01/2014\n RIP: 0010:btrfs_destroy_inode+0x1e6/0x210 [btrfs]\n RSP: 0018:ffffc9000327bda8 EFLAGS: 00010206\n RAX: 0000000000000000 RBX: ffff888100548b78 RCX: 0000000000000000\n RDX: 0000000000026900 RSI: 0000000000000000 RDI: ffff888100548b78\n RBP: ffff888100548940 R08: 0000000000000000 R09: ffff88810b48aba8\n R10: 0000000000000001 R11: ffff8881004eb240 R12: ffff88810b48a800\n R13: ffff88810b48ec08 R14: ffff88810b48ed00 R15: ffff888100490c68\n FS: 00007f8549ea0b80(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f854a09e733 CR3: 000000010a2e9003 CR4: 0000000000370eb0\n DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n Call Trace:\n <TASK>\n destroy_inode+0x33/0x70\n dispose_list+0x43/0x60\n evict_inodes+0x161/0x1b0\n generic_shutdown_super+0x2d/0x110\n kill_anon_super+0xf/0x20\n btrfs_kill_super+0xd/0x20 [btrfs]\n deactivate_locked_super+0x27/0x90\n cleanup_mnt+0x12c/0x180\n task_work_run+0x54/0x80\n exit_to_user_mode_prepare+0x152/0x160\n syscall_exit_to_user_mode+0x12/0x30\n do_syscall_64+0x42/0x80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n RIP: 0033:0x7f854a000fb7"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: libera la cantidad correcta de delalloc en la ruta de escritura de E/S directa. La ejecuci\u00f3n de generic/406 provoca la siguiente ADVERTENCIA en btrfs_destroy_inode() que indica que quedan extensiones pendientes. En btrfs_get_blocks_direct_write(), reservamos extensiones pendientes temporalmente con btrfs_delalloc_reserve_metadata() (o indirectamente desde btrfs_delalloc_reserve_space()). Luego, liberamos las extensiones pendientes con btrfs_delalloc_release_extents(). Sin embargo, la \"longitud\" se puede modificar en el caso de COW, que libera menos extensiones pendientes de lo esperado. Arr\u00e9glelo llamando a btrfs_delalloc_release_extents() para la longitud original. Para reproducir la advertencia, el sistema de archivos debe ser de 1 GiB. Est\u00e1 activando una escritura corta, debido a que no se puede asignar una extensi\u00f3n grande y, en su lugar, se asigna una m\u00e1s peque\u00f1a. ADVERTENCIA: CPU: 0 PID: 757 en fs/btrfs/inode.c:8848 btrfs_destroy_inode+0x1e6/0x210 [btrfs] M\u00f3dulos vinculados en: btrfs blake2b_generic xor lzo_compress lzo_decompress raid6_pq zstd zstd_decompress zstd_compress xxhash zram zsmalloc CPU: 0 PID: 757 Comm: umount No contaminado 5.17.0-rc8+ #101 Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996), BIOS d55cb5a 01/04/2014 RIP: 0010:btrfs_destroy_inode+0x1e6/0x210 [btrfs] RSP: 0018:ffffc9000327bda8 EFLAGS: 00010206 RAX: 000000000000000 RBX: ffff888100548b78 RCX: 0000000000000000 RDX: 0000000000026900 RSI: 0000000000000000 RDI: ffff888100548b78 RBP: ffff888100548940 R08: 0000000000000000 R09: ffff88810b48aba8 R10: 0000000000000001 R11: ffff8881004eb240 R12: ffff88810b48a800 R13: ffff88810b48ec08 R14: ffff88810b48ed00 R15: ffff888100490c68 FS: 00007f8549ea0b80(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f854a09e733 CR3: 000000010a2e9003 CR4: 0000000000370eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Seguimiento de llamadas: destroy_inode+0x33/0x70 dispose_list+0x43/0x60 evict_inodes+0x161/0x1b0 generic_shutdown_super+0x2d/0x110 kill_anon_super+0xf/0x20 btrfs_kill_super+0xd/0x20 [btrfs] deactivate_locked_super+0x27/0x90 cleanup_mnt+0x12c/0x180 task_work_run+0x54/0x80 exit_to_user_mode_prepare+0x152/0x160 syscall_exit_to_user_mode+0x12/0x30 do_syscall_64+0x42/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f854a000fb7"}], "lastModified": "2025-10-14T18:37:45.793", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4960A935-FD5B-4178-93FD-54F8B8F87E05", "versionEndExcluding": "5.15.35", "versionStartIncluding": "5.15.27"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "38DDBA33-1800-441A-9B01-A0A816DFB0C4", "versionEndExcluding": "5.17.4", "versionStartIncluding": "5.16.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6AD94161-84BB-42E6-9882-4FC0C42E9FC1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7AB06DDF-3C2B-416D-B448-E990D8FF67A9"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}