{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-05T08:00:35.455","vulnerabilities":[{"cve":{"id":"CVE-2021-47256","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-05-21T15:15:14.380","lastModified":"2025-04-30T15:05:57.057","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/memory-failure: make sure wait for page writeback in memory_failure\n\nOur syzkaller trigger the \"BUG_ON(!list_empty(&inode->i_wb_list))\" in\nclear_inode:\n\n  kernel BUG at fs/inode.c:519!\n  Internal error: Oops - BUG: 0 [#1] SMP\n  Modules linked in:\n  Process syz-executor.0 (pid: 249, stack limit = 0x00000000a12409d7)\n  CPU: 1 PID: 249 Comm: syz-executor.0 Not tainted 4.19.95\n  Hardware name: linux,dummy-virt (DT)\n  pstate: 80000005 (Nzcv daif -PAN -UAO)\n  pc : clear_inode+0x280/0x2a8\n  lr : clear_inode+0x280/0x2a8\n  Call trace:\n    clear_inode+0x280/0x2a8\n    ext4_clear_inode+0x38/0xe8\n    ext4_free_inode+0x130/0xc68\n    ext4_evict_inode+0xb20/0xcb8\n    evict+0x1a8/0x3c0\n    iput+0x344/0x460\n    do_unlinkat+0x260/0x410\n    __arm64_sys_unlinkat+0x6c/0xc0\n    el0_svc_common+0xdc/0x3b0\n    el0_svc_handler+0xf8/0x160\n    el0_svc+0x10/0x218\n  Kernel panic - not syncing: Fatal exception\n\nA crash dump of this problem show that someone called __munlock_pagevec\nto clear page LRU without lock_page: do_mmap -> mmap_region -> do_munmap\n-> munlock_vma_pages_range -> __munlock_pagevec.\n\nAs a result memory_failure will call identify_page_state without\nwait_on_page_writeback.  And after truncate_error_page clear the mapping\nof this page.  end_page_writeback won't call sb_clear_inode_writeback to\nclear inode->i_wb_list.  That will trigger BUG_ON in clear_inode!\n\nFix it by checking PageWriteback too to help determine should we skip\nwait_on_page_writeback."},{"lang":"es","value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm/memory-failure: asegúrese de esperar la reescritura de la página en Memory_failure. Nuestro syzkaller activa el \"BUG_ON(!list_empty(&inode->i_wb_list))\" en clear_inode: kernel BUG en fs /inodo.c:519! Error interno: Oops - BUG: 0 [#1] Módulos SMP vinculados en: Proceso syz-executor.0 (pid: 249, límite de pila = 0x00000000a12409d7) CPU: 1 PID: 249 Comm: syz-executor.0 No contaminado 4.19. 95 Nombre de hardware: linux,dummy-virt (DT) pstate: 80000005 (Nzcv daif -PAN -UAO) pc: clear_inode+0x280/0x2a8 lr: clear_inode+0x280/0x2a8 Rastreo de llamadas: clear_inode+0x280/0x2a8 ext4_clear_inode+0x38/0xe8 ext4_free_inode+0x130/0xc68 ext4_evict_inode+0xb20/0xcb8 desalojar+0x1a8/0x3c0 iput+0x344/0x460 do_unlinkat+0x260/0x410 __arm64_sys_unlinkat+0x6c/0xc0 el0_svc_common+0xdc /0x3b0 el0_svc_handler+0xf8/0x160 el0_svc+0x10/0x218 Pánico del kernel: no se sincroniza : Excepción fatal Un volcado de memoria de este problema muestra que alguien llamó a __munlock_pagevec para borrar la página LRU sin lock_page: do_mmap -> mmap_region -> do_munmap -> munlock_vma_pages_range -> __munlock_pagevec. Como resultado, Memory_failure llamará a identify_page_state sin wait_on_page_writeback. Y después de truncate_error_page, borre el mapeo de esta página. end_page_writeback no llamará a sb_clear_inode_writeback para borrar inode->i_wb_list. ¡Eso activará BUG_ON en clear_inode! Solucionarlo marcando también PageWriteback para ayudar a determinar si debemos omitir wait_on_page_writeback."}],"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":"NVD-CWE-noinfo"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.16","versionEndExcluding":"4.14.238","matchCriteriaId":"CC6F60EE-EF5A-4213-9927-5F26053B4B41"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"4.19.196","matchCriteriaId":"F3CAB837-7D38-4934-AD4F-195CEFD754E6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.20","versionEndExcluding":"5.4.128","matchCriteriaId":"6267BD4E-BE25-48B5-B850-4B493440DAFA"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.46","matchCriteriaId":"59455D13-A902-42E1-97F7-5ED579777193"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.12.13","matchCriteriaId":"7806E7E5-6D4F-4E18-81C1-79B3C60EE855"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*","matchCriteriaId":"0CBAD0FC-C281-4666-AB2F-F8E6E1165DF7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*","matchCriteriaId":"96AC23B2-D46A-49D9-8203-8E1BEDCA8532"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*","matchCriteriaId":"DA610E30-717C-4700-9F77-A3C9244F3BFD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*","matchCriteriaId":"1ECD33F5-85BE-430B-8F86-8D7BD560311D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*","matchCriteriaId":"CF351855-2437-4CF5-AD7C-BDFA51F27683"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*","matchCriteriaId":"25A855BA-2118-44F2-90EF-EBBB12AF51EF"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/28788dc5c70597395b6b451dae4549bbaa8e2c56","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/566345aaabac853aa866f53a219c4b02a6beb527","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/6d210d547adc2218ef8b5bcf23518c5f2f1fd872","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/9e379da727a7a031be9b877cde7b9c34a0fb8306","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d05267fd27a5c4f54e06daefa3035995d765ca0c","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e8675d291ac007e1c636870db880f837a9ea112a","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/28788dc5c70597395b6b451dae4549bbaa8e2c56","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/566345aaabac853aa866f53a219c4b02a6beb527","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/6d210d547adc2218ef8b5bcf23518c5f2f1fd872","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/9e379da727a7a031be9b877cde7b9c34a0fb8306","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/d05267fd27a5c4f54e06daefa3035995d765ca0c","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/e8675d291ac007e1c636870db880f837a9ea112a","source":"af854a3a-2127-422b-91ae-364da2661108","tags":["Patch"]}]}}]}