{ "id": "CVE-2024-50225", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2024-11-09T11:15:07.990", "lastModified": "2024-11-13T19:21:44.323", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix error propagation of split bios\n\nThe purpose of btrfs_bbio_propagate_error() shall be propagating an error\nof split bio to its original btrfs_bio, and tell the error to the upper\nlayer. However, it's not working well on some cases.\n\n* Case 1. Immediate (or quick) end_bio with an error\n\nWhen btrfs sends btrfs_bio to mirrored devices, btrfs calls\nbtrfs_bio_end_io() when all the mirroring bios are completed. If that\nbtrfs_bio was split, it is from btrfs_clone_bioset and its end_io function\nis btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error()\naccesses the orig_bbio's bio context to increase the error count.\n\nThat works well in most cases. However, if the end_io is called enough\nfast, orig_bbio's (remaining part after split) bio context may not be\nproperly set at that time. Since the bio context is set when the orig_bbio\n(the last btrfs_bio) is sent to devices, that might be too late for earlier\nsplit btrfs_bio's completion. That will result in NULL pointer\ndereference.\n\nThat bug is easily reproducible by running btrfs/146 on zoned devices [1]\nand it shows the following trace.\n\n[1] You need raid-stripe-tree feature as it create \"-d raid0 -m raid1\" FS.\n\n BUG: kernel NULL pointer dereference, address: 0000000000000020\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 0 P4D 0\n Oops: Oops: 0000 [#1] PREEMPT SMP PTI\n CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ #474\n Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n Workqueue: writeback wb_workfn (flush-btrfs-5)\n RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs]\n BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0\n RSP: 0018:ffffc9000006f248 EFLAGS: 00010246\n RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc\n RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080\n RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001\n R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58\n R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158\n FS: 0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0\n DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n Call Trace:\n \n ? __die_body.cold+0x19/0x26\n ? page_fault_oops+0x13e/0x2b0\n ? _printk+0x58/0x73\n ? do_user_addr_fault+0x5f/0x750\n ? exc_page_fault+0x76/0x240\n ? asm_exc_page_fault+0x22/0x30\n ? btrfs_bio_end_io+0xae/0xc0 [btrfs]\n ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs]\n btrfs_orig_write_end_io+0x51/0x90 [btrfs]\n dm_submit_bio+0x5c2/0xa50 [dm_mod]\n ? find_held_lock+0x2b/0x80\n ? blk_try_enter_queue+0x90/0x1e0\n __submit_bio+0xe0/0x130\n ? ktime_get+0x10a/0x160\n ? lockdep_hardirqs_on+0x74/0x100\n submit_bio_noacct_nocheck+0x199/0x410\n btrfs_submit_bio+0x7d/0x150 [btrfs]\n btrfs_submit_chunk+0x1a1/0x6d0 [btrfs]\n ? lockdep_hardirqs_on+0x74/0x100\n ? __folio_start_writeback+0x10/0x2c0\n btrfs_submit_bbio+0x1c/0x40 [btrfs]\n submit_one_bio+0x44/0x60 [btrfs]\n submit_extent_folio+0x13f/0x330 [btrfs]\n ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs]\n extent_writepage_io+0x18b/0x360 [btrfs]\n extent_write_locked_range+0x17c/0x340 [btrfs]\n ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs]\n run_delalloc_cow+0x71/0xd0 [btrfs]\n btrfs_run_delalloc_range+0x176/0x500 [btrfs]\n ? find_lock_delalloc_range+0x119/0x260 [btrfs]\n writepage_delalloc+0x2ab/0x480 [btrfs]\n extent_write_cache_pages+0x236/0x7d0 [btrfs]\n btrfs_writepages+0x72/0x130 [btrfs]\n do_writepages+0xd4/0x240\n ? find_held_lock+0x2b/0x80\n ? wbc_attach_and_unlock_inode+0x12c/0x290\n ? wbc_attach_and_unlock_inode+0x12c/0x29\n---truncated---" }, { "lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: corregir la propagaci\u00f3n de errores de bios divididas El prop\u00f3sito de btrfs_bbio_propagate_error() debe ser propagar un error de bio dividida a su btrfs_bio original y comunicar el error a la capa superior. Sin embargo, no est\u00e1 funcionando bien en algunos casos. * Caso 1. End_bio inmediato (o r\u00e1pido) con un error Cuando btrfs env\u00eda btrfs_bio a dispositivos reflejados, btrfs llama a btrfs_bio_end_io() cuando se completan todos los bios reflejados. Si ese btrfs_bio se dividi\u00f3, es de btrfs_clone_bioset y su funci\u00f3n end_io es btrfs_orig_write_end_io. Para este caso, btrfs_bbio_propagate_error() accede al contexto bio de orig_bbio para aumentar el recuento de errores. Eso funciona bien en la mayor\u00eda de los casos. Sin embargo, si se llama a end_io lo suficientemente r\u00e1pido, es posible que el contexto bio de orig_bbio (la parte restante despu\u00e9s de la divisi\u00f3n) no se configure correctamente en ese momento. Dado que el contexto bio se configura cuando se env\u00eda orig_bbio (el \u00faltimo btrfs_bio) a los dispositivos, puede que sea demasiado tarde para que se complete la divisi\u00f3n anterior de btrfs_bio. Eso dar\u00e1 como resultado la desreferencia del puntero NULL. Ese error se puede reproducir f\u00e1cilmente ejecutando btrfs/146 en dispositivos zonificados [1] y muestra el siguiente rastro. [1] Necesita la funci\u00f3n raid-stripe-tree, ya que crea el sistema de archivos \"-d raid0 -m raid1\". ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000020 #PF: acceso de lectura del supervisor en modo kernel #PF: error_code(0x0000) - p\u00e1gina no presente PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 No contaminado 6.11.0-rc7-BTRFS-ZNS+ #474 Nombre del hardware: Bochs Bochs, BIOS Bochs 01/01/2011 Cola de trabajo: escritura diferida wb_workfn (flush-btrfs-5) RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs] Error BTRFS (dispositivo dm-0): bdev /dev/mapper/error-test errores: wr 2, rd 0, vaciado 0, corrupto 0, generaci\u00f3n 0 RSP: 0018:ffffc9000006f248 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080 RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58 R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158 FS: 000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0 DR0: 00000000000000000 DR1: 00000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Seguimiento de llamadas: ? __die_body.cold+0x19/0x26 ? page_fault_oops+0x13e/0x2b0 ? _printk+0x58/0x73 ? do_user_addr_fault+0x5f/0x750 ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs] btrfs_orig_write_end_io+0x51/0x90 [btrfs] dm_submit_bio+0x5c2/0xa50 [dm_mod] ? blk_try_enter_queue+0x90/0x1e0 __submit_bio+0xe0/0x130 ? ktime_get+0x10a/0x160 ? lockdep_hardirqs_on+0x74/0x100 submit_bio_noacct_nocheck+0x199/0x410 btrfs_submit_bio+0x7d/0x150 [btrfs] btrfs_submit_chunk+0x1a1/0x6d0 [btrfs]? lockdep_hardirqs_on+0x74/0x100? __folio_start_writeback+0x10/0x2c0 btrfs_submit_bbio+0x1c/0x40 [btrfs] submit_one_bio+0x44/0x60 [btrfs] submit_extent_folio+0x13f/0x330 [btrfs] ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs] extend_writepage_io+0x18b/0x360 [btrfs] extend_write_locked_range+0x17c/0x340 [btrfs] ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs] run_delalloc_cow+0x71/0xd0 [btrfs] btrfs_run_delalloc_range+0x176/0x500 [btrfs] ? buscar_bloqueo_desbloqueado_rango+0x119/0x260 [btrfs] escribir_p\u00e1gina_desbloqueado+0x2ab/0x480 [btrfs] extensi\u00f3n_escritura_p\u00e1ginas_cach\u00e9+0x236/0x7d0 [btrfs] btrfs_escritura_p\u00e1ginas+0x72/0x130 [btrfs] hacer_escritura_p\u00e1ginas+0xd4/0x240 ? buscar_bloqueo_retenido+0x2b/0x80 ? wbc_adjuntar_y_desbloquear_inodo+0x12c/0x290 ? wbc_adjuntar_y_desbloquear_inodo+0x12c/0x29 ---truncado---" } ], "metrics": { "cvssMetricV31": [ { "source": "nvd@nist.gov", "type": "Primary", "cvssData": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH" }, "exploitabilityScore": 1.8, "impactScore": 3.6 } ] }, "weaknesses": [ { "source": "nvd@nist.gov", "type": "Primary", "description": [ { "lang": "en", "value": "CWE-476" } ] } ], "configurations": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.3", "versionEndExcluding": "6.11.7", "matchCriteriaId": "5972B133-90E2-44DE-AE0B-A0939F0D914F" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:*", "matchCriteriaId": "7F361E1D-580F-4A2D-A509-7615F73167A1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:*", "matchCriteriaId": "925478D0-3E3D-4E6F-ACD5-09F28D5DF82C" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:*", "matchCriteriaId": "3C95E234-D335-4B6C-96BF-E2CEBD8654ED" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:*", "matchCriteriaId": "E0F717D8-3014-4F84-8086-0124B2111379" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc5:*:*:*:*:*:*", "matchCriteriaId": "24DBE6C7-2AAE-4818-AED2-E131F153D2FA" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/22833d89b780ba0f9f66e19c477e7decf638edce", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ] }, { "url": "https://git.kernel.org/stable/c/d48e1dea3931de64c26717adc2b89743c7ab6594", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": [ "Patch" ] } ] }