{"schema":"threatline.record/2","record":{"id":"CVE-2026-97549","aliases":[],"summary":"xfs: fix under-reservation of blocks when repairing sf directories","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: fix under-reservation of blocks when repairing sf directories\n\nWhilst running QA on XFS for-next as of 7.3-rc2 with MKFS_OPTIONS=\"-n\nsize=8192\", I observed the following (trimmed) dmesg splat:\n\n XFS: Assertion failed: args->total >= dp->i_nblocks - nblks, file: fs/xfs/libxfs/xfs_da_btree.c, line: 2387\n WARNING: fs/xfs/xfs_message.c:104 at assfail+0x46/0x4a [xfs], CPU#0: xfs_scrub/1426511\n CPU: 0 UID: 0 PID: 1426511 Comm: xfs_scrub Tainted: G        W           7.3.0-rc2-djwx #rc2 PREEMPT(lazy)  6e418570b606a39783b0e7e7b30dc407b965f9e8\n Tainted: [W]=WARN\n RIP: 0010:assfail+0x46/0x4a [xfs]\n RSP: 0018:ffffc900010d7890 EFLAGS: 00010246\n RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000ffffffd1\n RDX: 0000000000000000 RSI: 0000000000000021 RDI: ffffffffa059fd38\n RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000\n R10: 000000000000000a R11: 000000007fffffff R12: ffffc900010d7940\n R13: ffff888368d8f980 R14: ffffc900010d7a48 R15: ffffc900010d78d0\n FS:  00007f445c5ce680(0000) GS:ffff8884a97ea000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f443803b9a8 CR3: 0000000107a4b000 CR4: 00000000003506f0\n Call Trace:\n  <TASK>\n  xfs_da_grow_inode_int+0x2e0/0x300 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xfs_dir2_grow_inode+0x6e/0x150 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xfs_dir2_sf_to_block+0x149/0x870 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xrep_dir_swap_prep+0xe2/0x110 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xrep_dir_swap+0xfb/0x2f0 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xrep_dir_rebuild_tree+0x99/0x100 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xrep_directory+0x83/0x1c0 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xrep_attempt+0x4f/0x1e0 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xfs_scrub_metadata+0x393/0x5b0 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xfs_ioc_scrubv_metadata+0x306/0x570 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  xfs_file_ioctl+0xa4f/0x1150 [xfs 5de2257e14108c136f11317e6bbb8ac77efd392c]\n  __x64_sys_ioctl+0x76/0xc0\n  do_syscall_64+0x7a/0x3b0\n  entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\nThis is a consequence of commit 0fe77e57588b98, which added the\nfollowing assertion to xfs_da_grow_inode_int:\n\n ASSERT(args->total >= dp->i_nblocks - nblks);\n\nTracing this back to xrep_dir_swap_prep, I noticed that the xfs_da_args\nobject that's passed to xfs_dir2_sf_to_block sets args->total to 1.\nThis is incorrect because mkfs set the directory block size to 8k and\nthe filesystem block size to 4k.  In other words, args->total should be\n2 here, not 1.\n\nDave Chinner tripped over the same problem with the same branch through\na different channel -- his test setup set the fs block size to 1k, in\nwhich case the directory block size is still set to 4k.  Here,\nargs->total should be 4.\n\nChanging the assignment of args->total to sc->mp->m_dir_geo->fsbcount\nmakes the assertion go away, but that isn't a complete fix.  In\nxrep_tempexch_estimate, we also incorrectly assume that a shortform\nconversion requires 1 fsblock when it should be m_dir_geo->fsbcount.\nWithout that, we can under-reserve space in the transaction and cause a\nfilesystem shutdown.\n\nNote that the xfs_dabuf_nfsb helper will compute the correct value for\ndirectories and xattr, so we use that instead of open-coding the logic.\nAlso fix xrep_xattr_swap_prep to assign args->total via xfs_dabuf_nfsb\nto avoid one logic bomb if we ever support multi-fsblock attrs.\n\nTripped-by: 0fe77e57588b98 (\"xfs: assert the reservation covers each da fork growth\")","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97549","source_modified_at":"2026-10-19T09:09:12.382Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"629fdaf5f5b1b7f7107ed4de04e0991a99501ced","lessThan":"996cce0c422b66a0e8b1a99505f896b0669ee5b6","status":"affected","versionType":"git"},{"version":"629fdaf5f5b1b7f7107ed4de04e0991a99501ced","lessThan":"b8f46ca5cbd629ffb91489ad7f970b3837835b0a","status":"affected","versionType":"git"},{"version":"629fdaf5f5b1b7f7107ed4de04e0991a99501ced","lessThan":"b950e84acd072ac648ace4fea53c0b1212da4b2c","status":"affected","versionType":"git"},{"version":"629fdaf5f5b1b7f7107ed4de04e0991a99501ced","lessThan":"4d3c07591534517c633945c8d8e6526f10e3fabc","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97549","source_modified_at":"2026-10-19T09:09:12.382Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"6.10","status":"affected"},{"version":"0","lessThan":"6.10","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.54","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.7","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97549","source_modified_at":"2026-10-19T09:09:12.382Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"996cce0c422b66a0e8b1a99505f896b0669ee5b6","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-97549","source_modified_at":"2026-10-19T09:09:12.382Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"4d3c07591534517c633945c8d8e6526f10e3fabc","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.002,"percentile":0.09319,"score_date":"2026-10-23"},"published_at":"2026-09-25T10:21:42.852Z","modified_at":"2026-10-19T09:09:12.382Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-97549","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:09:12.382Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-97549","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/996cce0c422b66a0e8b1a99505f896b0669ee5b6"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/b8f46ca5cbd629ffb91489ad7f970b3837835b0a"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/b950e84acd072ac648ace4fea53c0b1212da4b2c"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/4d3c07591534517c633945c8d8e6526f10e3fabc"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:09:12.382Z","content_hash":"35f94295d865a84aabacfa8b71d2fdd0d7fac1f68a7fb7ce8527b345c93a1a81"}}