{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2024-26868", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-26868", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2024-04-17T10:27:29.431Z", "updatedAt": "2026-08-05T11:27:55.702Z", "importedAt": "2026-10-24T01:57:07.518Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "nfs: fix panic when nfs4_ff_layout_prepare_ds() fails", "summary": "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 \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.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "b739a5bd9d9f18cc69dced8db128ef7206e000cd", "status": "affected", "versionType": "git", "lessThan": "31db25e3141b20e2a76a9f219eeca52e3cab126c" }, { "version": "b739a5bd9d9f18cc69dced8db128ef7206e000cd", "status": "affected", "versionType": "git", "lessThan": "7ca651b4ec4a049f5a46a0e5ff921b86b91c47c5" }, { "version": "b739a5bd9d9f18cc69dced8db128ef7206e000cd", "status": "affected", "versionType": "git", "lessThan": "5ada9016b1217498fad876a3d5b07645cc955608" }, { "version": "b739a5bd9d9f18cc69dced8db128ef7206e000cd", "status": "affected", "versionType": "git", "lessThan": "dac068f164ad05b35e7c0be13f138c3f6adca58f" }, { "version": "b739a5bd9d9f18cc69dced8db128ef7206e000cd", "status": "affected", "versionType": "git", "lessThan": "719fcafe07c12646691bd62d7f8d94d657fa0766" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "6.1", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "6.1" }, { "version": "6.1.83", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.23", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.7.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.7.*" }, { "version": "6.8.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.8.*" }, { "version": "6.9", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }