{"cve":"CVE-2026-93235","nvd":{"published":"2026-09-24T16:17:19.150","modified":"2026-10-19T10:17:14.553","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to zero post-EOF data when extending file size\n\ngeneric/794  4s ... - output mismatch (see /share/git/fstests/results//generic/794.out.bad)\n    --- tests/generic/794.out   2026-06-12 08:46:32.766426241 +0800\n    +++ /share/git/fstests/results//generic/794.out.bad 2026-07-05 18:32:55.000000000 +0800\n    @@ -1,4 +1,16 @@\n     QA output created by 794\n     append_write\n    +FAIL: non-zero data in gap [4080,4096) after shutdown+remount\n    +000000 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a  >ZZZZZZZZZZZZZZZZ<\n    +*\n    +001000\n     truncate_up\n    ...\n    (Run 'diff -u /share/git/fstests/tests/generic/794.out /share/git/fstests/results//generic/794.out.bad'  to see the entire diff)\nRan: generic/794\nFailures: generic/794\nFailed 1 of 1 tests\n\nSteps of generic/794:\n1. write 4096 bytes to file w/ 0x5a\n2. use fiemap to get PBA of first block in file\n3. truncate file to 4080\n4. umount; write 4096 bytes to file w/ 0x5a directly via PBA; mount\n5. extend filesize via\n   a) append 4096 from offset 4096, or\n   b) truncate 8192, or\n   c) fallocate 4096 from offset 4096\n6. verify the gap is zeroed in memory [4080,4096)\n7. sync range 4096 from offset 4096; shutdown -f (flush meta before shutdown)\n8. umount; mount; verify [4080,4096) is zeroed or not.\n\nWhen extending file size (e.g. via truncate, fallocate, or write) across an\nunaligned EOF boundary, we need to ensure that post-EOF data in the partial\npage is zeroed out in pagecache and marked dirty, then writeback the cache to\npersist zeroed data before committing inode w/ updated i_size.\n\nThis help to prevent stale disk data beyond the previous EOF from being exposed\nafter remounting or crash recovery.\n\nSince f2fs is a LFS filesystem, we only support direct write via PBA in pinfile,\nand pinfile has section-aligned filesize, so in Android, there should no problem,\nbut for other usage in different environment, let's fix this w/ fsync_mode=strict\nmount option.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/32c7f11a24268ba8d3bb50ea7f54d33f698cd253","https://git.kernel.org/stable/c/5eced87b7d19dbc76ebdddaf322046f9ac582fcb","https://git.kernel.org/stable/c/6882d458d2e403f6ba7b45542dd31a6b7531eb2e","https://git.kernel.org/stable/c/91ec55ddc097ccddd25ffb95a3d079b2ef362372","https://git.kernel.org/stable/c/c42608c09b6b5d5967bf211c255914c068c2cde1"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-93235","score":0.00209,"percentile":0.10984,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}