{"id":"CVE-2026-90131","revision":"32c1740815a3481fa8b53464a3636e57","records":[{"revision":"32c1740815a3481fa8b53464a3636e57","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90131","aliases":[],"title":"ntfs: serialize resident iomap reads with mrec_lock","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: serialize resident iomap reads with mrec_lock\n\nntfs_read_iomap_begin_resident() walks the MFT record through\nntfs_attr_lookup() -> ntfs_attr_find() without taking ni->mrec_lock,\nwhile ntfs_attr_record_resize(), ntfs_make_room_for_attr() and\nntfs_resident_attr_record_add() memmove() the same base_ni->mrec buffer\nunder that lock. map_mft_record() only takes a reference and does not\nserialize, so the reader can observe torn attribute length and offset\nfields while a writer is relocating the records.\n\nKCSAN reports the race between the mmap read fault path and both link()\nand unlink():\n\n  BUG: KCSAN: data-race in ntfs_attr_find / ntfs_attr_record_resize\n\n  write to 0xffff888100af1018 of 4 bytes by task 96 on cpu 1:\n   ntfs_attr_record_resize+0xd2/0x130\n   ntfs_attr_record_rm+0xad/0x530\n   ntfs_delete+0x224/0x640\n   ntfs_unlink+0x14d/0x280\n   vfs_unlink+0x157/0x520\n\n  read to 0xffff888100af1018 of 4 bytes by task 95 on cpu 0:\n   ntfs_attr_find+0x104/0x5b0\n   ntfs_attr_lookup+0x39c/0x10c0\n   ntfs_read_iomap_begin_resident+0xc6/0x230\n   ntfs_read_iomap_begin+0x5d/0xa0\n   iomap_iter+0x2e2/0x6e0\n   iomap_read_folio+0x147/0x2a0\n   ntfs_read_folio+0x108/0x170\n   filemap_read_folio+0x35/0x100\n   filemap_fault+0x993/0x1000\n\n  value changed: 0x00000250 -> 0x000001f0\n\nThe address is mrec + 0x18, i.e. mft_record.bytes_in_use, and the change\nis the 96 bytes of one $FILE_NAME attribute being removed.\n\nKeep base_ni->mrec_lock from the resident read iomap lookup through\niomap_end(). This protects both the attribute walk and the subsequent copy\nfrom iomap->inline_data, which points into the MFT record. The non-resident\npath is left alone: ntfs_lookup() already holds the directory inode's\nmrec_lock when it reads an index folio through read_mapping_folio(), and\ntaking the lock in the shared wrapper deadlocks there with recursive locking\non mrec_lock. The comment above the read_mapping_folio() call in\nfs/ntfs/dir.c notes the same hazard.\n\nThe seek path uses the same lookup helper but does not dereference\niomap->inline_data. Release the lock before returning from that path,\nwhereas the regular read path records base_ni in iomap->private and releases\nthe lock from its iomap_end() callback.\n\nTested with a reproducer that faults in a 16-byte resident file while\nanother thread runs link()/unlink() on it. Before: 40 KCSAN reports in\nabout one second. After: no reports in 180 seconds over 206,090 read\niterations and 423,540 link/unlink cycles. A PROVE_LOCKING build shows no\nlockdep splat with the same reproducer running for 60 seconds.","state":0,"publishedAt":"2026-09-17T16:06:31.913+00:00","modifiedAt":"2026-10-19T08:58:29.513+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/ntfs/iomap.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"b041ca562526b3c4a71b41b80ba5e520eac636ad\",\n                            \"lessThan\": \"0400e0d50eb3be19c98323faa322b652e4ae3f99\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"b041ca562526b3c4a71b41b80ba5e520eac636ad\",\n                            \"lessThan\": \"d9e00c457d4ab8ab59c6e4b8554c921260e4e16c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/ntfs/iomap.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.1\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/0400e0d50eb3be19c98323faa322b652e4ae3f99","https://git.kernel.org/stable/c/d9e00c457d4ab8ab59c6e4b8554c921260e4e16c"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90131","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90131","identifiers":["CVE-2026-90131"]},"retained":false,"historicalAffected":[]}],"coverage":[]}