{"api_version":"1","generated_at":"2026-08-05T02:22:38+00:00","cve":"CVE-2024-26868","urls":{"html":"https://cve.report/CVE-2024-26868","api":"https://cve.report/api/cve/CVE-2024-26868.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2024-26868","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-26868"},"summary":{"title":"nfs: fix panic when nfs4_ff_layout_prepare_ds() fails","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfs: fix panic when nfs4_ff_layout_prepare_ds() fails\n\nWe've been seeing the following panic in production\n\nBUG: kernel NULL pointer dereference, address: 0000000000000065\nPGD 2f485f067 P4D 2f485f067 PUD 2cc5d8067 PMD 0\nRIP: 0010:ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\nCall Trace:\n <TASK>\n ? __die+0x78/0xc0\n ? page_fault_oops+0x286/0x380\n ? __rpc_execute+0x2c3/0x470 [sunrpc]\n ? rpc_new_task+0x42/0x1c0 [sunrpc]\n ? exc_page_fault+0x5d/0x110\n ? asm_exc_page_fault+0x22/0x30\n ? ff_layout_free_layoutreturn+0x110/0x110 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x6f/0x90 [nfs_layout_flexfiles]\n pnfs_mark_matching_lsegs_return+0x1b0/0x360 [nfsv4]\n pnfs_error_mark_layout_for_return+0x9e/0x110 [nfsv4]\n ? ff_layout_send_layouterror+0x50/0x160 [nfs_layout_flexfiles]\n nfs4_ff_layout_prepare_ds+0x11f/0x290 [nfs_layout_flexfiles]\n ff_layout_pg_init_write+0xf0/0x1f0 [nfs_layout_flexfiles]\n __nfs_pageio_add_request+0x154/0x6c0 [nfs]\n nfs_pageio_add_request+0x26b/0x380 [nfs]\n nfs_do_writepage+0x111/0x1e0 [nfs]\n nfs_writepages_callback+0xf/0x30 [nfs]\n write_cache_pages+0x17f/0x380\n ? nfs_pageio_init_write+0x50/0x50 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n nfs_writepages+0x125/0x210 [nfs]\n do_writepages+0x67/0x220\n ? generic_perform_write+0x14b/0x210\n filemap_fdatawrite_wbc+0x5b/0x80\n file_write_and_wait_range+0x6d/0xc0\n nfs_file_fsync+0x81/0x170 [nfs]\n ? nfs_file_mmap+0x60/0x60 [nfs]\n __x64_sys_fsync+0x53/0x90\n do_syscall_64+0x3d/0x90\n entry_SYSCALL_64_after_hwframe+0x46/0xb0\n\nInspecting the core with drgn I was able to pull this\n\n  >>> prog.crashed_thread().stack_trace()[0]\n  #0 at 0xffffffffa079657a (ff_layout_cancel_io+0x3a/0x84) in ff_layout_cancel_io at fs/nfs/flexfilelayout/flexfilelayout.c:2021:27\n  >>> prog.crashed_thread().stack_trace()[0]['idx']\n  (u32)1\n  >>> prog.crashed_thread().stack_trace()[0]['flseg'].mirror_array[1].mirror_ds\n  (struct nfs4_ff_layout_ds *)0xffffffffffffffed\n\nThis is clear from the stack trace, we call nfs4_ff_layout_prepare_ds()\nwhich could error out initializing the mirror_ds, and then we go to\nclean it all up and our check is only for if (!mirror->mirror_ds).  This\nis inconsistent with the rest of the users of mirror_ds, which have\n\n  if (IS_ERR_OR_NULL(mirror_ds))\n\nto keep from tripping over this exact scenario.  Fix this up in\nff_layout_cancel_io() to make sure we don't panic when we get an error.\nI also spot checked all the other instances of checking mirror_ds and we\nappear to be doing the correct checks everywhere, only unconditionally\ndereferencing mirror_ds when we know it would be valid.","state":"PUBLISHED","assigner":"Linux","published_at":"2024-04-17 11:15:09","updated_at":"2026-08-04 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Container"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/nfs/flexfilelayout/flexfilelayout.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"31db25e3141b20e2a76a9f219eeca52e3cab126c","status":"affected","version":"b739a5bd9d9f18cc69dced8db128ef7206e000cd","versionType":"git"},{"lessThan":"7ca651b4ec4a049f5a46a0e5ff921b86b91c47c5","status":"affected","version":"b739a5bd9d9f18cc69dced8db128ef7206e000cd","versionType":"git"},{"lessThan":"5ada9016b1217498fad876a3d5b07645cc955608","status":"affected","version":"b739a5bd9d9f18cc69dced8db128ef7206e000cd","versionType":"git"},{"lessThan":"dac068f164ad05b35e7c0be13f138c3f6adca58f","status":"affected","version":"b739a5bd9d9f18cc69dced8db128ef7206e000cd","versionType":"git"},{"lessThan":"719fcafe07c12646691bd62d7f8d94d657fa0766","status":"affected","version":"b739a5bd9d9f18cc69dced8db128ef7206e000cd","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/nfs/flexfilelayout/flexfilelayout.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.1"},{"lessThan":"6.1","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.83","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.23","versionType":"semver"},{"lessThanOrEqual":"6.7.*","status":"unaffected","version":"6.7.11","versionType":"semver"},{"lessThanOrEqual":"6.8.*","status":"unaffected","version":"6.8.2","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.9","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.83","versionStartIncluding":"6.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.23","versionStartIncluding":"6.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.7.11","versionStartIncluding":"6.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.8.2","versionStartIncluding":"6.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.9","versionStartIncluding":"6.1","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfs: fix panic when nfs4_ff_layout_prepare_ds() fails\n\nWe've been seeing the following panic in production\n\nBUG: kernel NULL pointer dereference, address: 0000000000000065\nPGD 2f485f067 P4D 2f485f067 PUD 2cc5d8067 PMD 0\nRIP: 0010:ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\nCall Trace:\n <TASK>\n ? __die+0x78/0xc0\n ? page_fault_oops+0x286/0x380\n ? __rpc_execute+0x2c3/0x470 [sunrpc]\n ? rpc_new_task+0x42/0x1c0 [sunrpc]\n ? exc_page_fault+0x5d/0x110\n ? asm_exc_page_fault+0x22/0x30\n ? ff_layout_free_layoutreturn+0x110/0x110 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x6f/0x90 [nfs_layout_flexfiles]\n pnfs_mark_matching_lsegs_return+0x1b0/0x360 [nfsv4]\n pnfs_error_mark_layout_for_return+0x9e/0x110 [nfsv4]\n ? ff_layout_send_layouterror+0x50/0x160 [nfs_layout_flexfiles]\n nfs4_ff_layout_prepare_ds+0x11f/0x290 [nfs_layout_flexfiles]\n ff_layout_pg_init_write+0xf0/0x1f0 [nfs_layout_flexfiles]\n __nfs_pageio_add_request+0x154/0x6c0 [nfs]\n nfs_pageio_add_request+0x26b/0x380 [nfs]\n nfs_do_writepage+0x111/0x1e0 [nfs]\n nfs_writepages_callback+0xf/0x30 [nfs]\n write_cache_pages+0x17f/0x380\n ? nfs_pageio_init_write+0x50/0x50 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n nfs_writepages+0x125/0x210 [nfs]\n do_writepages+0x67/0x220\n ? generic_perform_write+0x14b/0x210\n filemap_fdatawrite_wbc+0x5b/0x80\n file_write_and_wait_range+0x6d/0xc0\n nfs_file_fsync+0x81/0x170 [nfs]\n ? nfs_file_mmap+0x60/0x60 [nfs]\n __x64_sys_fsync+0x53/0x90\n do_syscall_64+0x3d/0x90\n entry_SYSCALL_64_after_hwframe+0x46/0xb0\n\nInspecting the core with drgn I was able to pull this\n\n  >>> prog.crashed_thread().stack_trace()[0]\n  #0 at 0xffffffffa079657a (ff_layout_cancel_io+0x3a/0x84) in ff_layout_cancel_io at fs/nfs/flexfilelayout/flexfilelayout.c:2021:27\n  >>> prog.crashed_thread().stack_trace()[0]['idx']\n  (u32)1\n  >>> prog.crashed_thread().stack_trace()[0]['flseg'].mirror_array[1].mirror_ds\n  (struct nfs4_ff_layout_ds *)0xffffffffffffffed\n\nThis is clear from the stack trace, we call nfs4_ff_layout_prepare_ds()\nwhich could error out initializing the mirror_ds, and then we go to\nclean it all up and our check is only for if (!mirror->mirror_ds).  This\nis inconsistent with the rest of the users of mirror_ds, which have\n\n  if (IS_ERR_OR_NULL(mirror_ds))\n\nto keep from tripping over this exact scenario.  Fix this up in\nff_layout_cancel_io() to make sure we don't panic when we get an error.\nI also spot checked all the other instances of checking mirror_ds and we\nappear to be doing the correct checks everywhere, only unconditionally\ndereferencing mirror_ds when we know it would be valid."}],"metrics":[{"cvssV3_1":{"baseScore":7.5,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-08-04T09:20:53.501Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/31db25e3141b20e2a76a9f219eeca52e3cab126c"},{"url":"https://git.kernel.org/stable/c/7ca651b4ec4a049f5a46a0e5ff921b86b91c47c5"},{"url":"https://git.kernel.org/stable/c/5ada9016b1217498fad876a3d5b07645cc955608"},{"url":"https://git.kernel.org/stable/c/dac068f164ad05b35e7c0be13f138c3f6adca58f"},{"url":"https://git.kernel.org/stable/c/719fcafe07c12646691bd62d7f8d94d657fa0766"}],"title":"nfs: fix panic when nfs4_ff_layout_prepare_ds() fails","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2024-26868","datePublished":"2024-04-17T10:27:29.431Z","dateReserved":"2024-02-19T14:20:24.184Z","dateUpdated":"2026-08-04T09:20:53.501Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2024-04-17 11:15:09","lastModifiedDate":"2026-08-04 11:17:15","problem_types":["CWE-476"],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6},{"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}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2024-05-28T19:56:48.883135Z","id":"CVE-2024-26868","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.1.83","matchCriteriaId":"3057E4AB-0FB4-49B3-B63D-10D187B96B1B"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.23","matchCriteriaId":"E00814DC-0BA7-431A-9926-80FEB4A96C68"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.7.11","matchCriteriaId":"9B95D3A6-E162-47D5-ABFC-F3FA74FA7CFD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.8.2","matchCriteriaId":"543A75FF-25B8-4046-A514-1EA8EDD87AB1"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2024","CveId":"26868","Ordinal":"1","Title":"nfs: fix panic when nfs4_ff_layout_prepare_ds() fails","CVE":"CVE-2024-26868","Year":"2024"},"notes":[{"CveYear":"2024","CveId":"26868","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfs: fix panic when nfs4_ff_layout_prepare_ds() fails\n\nWe've been seeing the following panic in production\n\nBUG: kernel NULL pointer dereference, address: 0000000000000065\nPGD 2f485f067 P4D 2f485f067 PUD 2cc5d8067 PMD 0\nRIP: 0010:ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\nCall Trace:\n <TASK>\n ? __die+0x78/0xc0\n ? page_fault_oops+0x286/0x380\n ? __rpc_execute+0x2c3/0x470 [sunrpc]\n ? rpc_new_task+0x42/0x1c0 [sunrpc]\n ? exc_page_fault+0x5d/0x110\n ? asm_exc_page_fault+0x22/0x30\n ? ff_layout_free_layoutreturn+0x110/0x110 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles]\n ? ff_layout_cancel_io+0x6f/0x90 [nfs_layout_flexfiles]\n pnfs_mark_matching_lsegs_return+0x1b0/0x360 [nfsv4]\n pnfs_error_mark_layout_for_return+0x9e/0x110 [nfsv4]\n ? ff_layout_send_layouterror+0x50/0x160 [nfs_layout_flexfiles]\n nfs4_ff_layout_prepare_ds+0x11f/0x290 [nfs_layout_flexfiles]\n ff_layout_pg_init_write+0xf0/0x1f0 [nfs_layout_flexfiles]\n __nfs_pageio_add_request+0x154/0x6c0 [nfs]\n nfs_pageio_add_request+0x26b/0x380 [nfs]\n nfs_do_writepage+0x111/0x1e0 [nfs]\n nfs_writepages_callback+0xf/0x30 [nfs]\n write_cache_pages+0x17f/0x380\n ? nfs_pageio_init_write+0x50/0x50 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n ? nfs_writepages+0x6d/0x210 [nfs]\n nfs_writepages+0x125/0x210 [nfs]\n do_writepages+0x67/0x220\n ? generic_perform_write+0x14b/0x210\n filemap_fdatawrite_wbc+0x5b/0x80\n file_write_and_wait_range+0x6d/0xc0\n nfs_file_fsync+0x81/0x170 [nfs]\n ? nfs_file_mmap+0x60/0x60 [nfs]\n __x64_sys_fsync+0x53/0x90\n do_syscall_64+0x3d/0x90\n entry_SYSCALL_64_after_hwframe+0x46/0xb0\n\nInspecting the core with drgn I was able to pull this\n\n  >>> prog.crashed_thread().stack_trace()[0]\n  #0 at 0xffffffffa079657a (ff_layout_cancel_io+0x3a/0x84) in ff_layout_cancel_io at fs/nfs/flexfilelayout/flexfilelayout.c:2021:27\n  >>> prog.crashed_thread().stack_trace()[0]['idx']\n  (u32)1\n  >>> prog.crashed_thread().stack_trace()[0]['flseg'].mirror_array[1].mirror_ds\n  (struct nfs4_ff_layout_ds *)0xffffffffffffffed\n\nThis is clear from the stack trace, we call nfs4_ff_layout_prepare_ds()\nwhich could error out initializing the mirror_ds, and then we go to\nclean it all up and our check is only for if (!mirror->mirror_ds).  This\nis inconsistent with the rest of the users of mirror_ds, which have\n\n  if (IS_ERR_OR_NULL(mirror_ds))\n\nto keep from tripping over this exact scenario.  Fix this up in\nff_layout_cancel_io() to make sure we don't panic when we get an error.\nI also spot checked all the other instances of checking mirror_ds and we\nappear to be doing the correct checks everywhere, only unconditionally\ndereferencing mirror_ds when we know it would be valid.","Type":"Description","Title":"nfs: fix panic when nfs4_ff_layout_prepare_ds() fails"}]}}}