{"id":"CVE-2026-90096","revision":"790d4853cbbe452b8a3a6dba146a3cf9","records":[{"revision":"790d4853cbbe452b8a3a6dba146a3cf9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-90096","aliases":[],"title":"fuse: invalidate the correct range after O_APPEND direct write","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: invalidate the correct range after O_APPEND direct write\n\nfuse_direct_write_iter() captures pos before generic_write_checks(),\nwhich moves ki_pos to EOF for O_APPEND writes:\n\n  fuse_direct_write_iter()\n  {\n      pos = iocb->ki_pos;           /* 0 (user-supplied)       */\n      generic_write_checks();       /* ki_pos -> EOF           */\n      fuse_direct_io();             /* writes at EOF, correct  */\n      invalidate(pos, pos + res);   /* [0, res) -- wrong       */\n  }\n\nThe post-write invalidation targets a stale range instead of the\nactual written range at EOF.\n\nThis can cause data inconsistency when the file size is not\npage-aligned.  The tail page straddling EOF has a valid portion\nbefore EOF that concurrent readers can fault back in during the\nDIO write window:\n\n  Tail page (file size X not page-aligned):\n\n    page_start         X (EOF)   page_end\n    |--- valid data ----|-- stale --|\n\n  CPU0 (O_APPEND DIO writer)    CPU1 (buffered reader)\n  --------------------------    ----------------------\n  invalidate [X, X+len)\n    tail page evicted\n  FUSE_WRITE in flight ...\n                                read [page_start, X)\n                                  tail page re-faulted\n                                  [X, page_end) = stale\n  FUSE_WRITE completes\n  i_size = X + len\n  invalidate [0, len)  <- WRONG\n    tail page still cached\n                                read [X, X+len)\n                                  hits stale tail page\n                                  returns old data\n\nFix by reading pos back from iocb->ki_pos after generic_write_checks(),\nas generic_file_direct_write() does.\n\nAlso fix a typo in the comment (\"may have\" -> \"may have competed\").","state":0,"publishedAt":"2026-09-17T16:06:08.87+00:00","modifiedAt":"2026-10-19T08:57:54.506+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/fuse/file.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2b0408d0284f4ff376cf5610fa8c9905e93c2541\",\n                            \"lessThan\": \"833963069adf86dcbdffd4e7d7b3171f95070b77\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"2b0408d0284f4ff376cf5610fa8c9905e93c2541\",\n                            \"lessThan\": \"26d7e1f5c407b5859122b5cd47d7ebbf4b4c1cd2\",\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/fuse/file.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.2\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.2\",\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":[],"references":["https://git.kernel.org/stable/c/833963069adf86dcbdffd4e7d7b3171f95070b77","https://git.kernel.org/stable/c/26d7e1f5c407b5859122b5cd47d7ebbf4b4c1cd2"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-90096","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-90096","identifiers":["CVE-2026-90096"]},"retained":false,"historicalAffected":[]}],"coverage":[]}