{"id":"CVE-2026-90279","published":"2026-09-17T17:17:24.567","lastModified":"2026-09-17T17:17:24.567","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmd/raid5: round bitmap stripes with sector division\n\nraid5_bitmap_sector_map() aligns the array range to full RAID5 stripe\nwidths before converting it to component sectors. That width is\nchunk_sectors multiplied by the number of data disks, and it is not\nalways a power of two.\n\nReproduce with a 4-disk RAID5, 1024-sector chunks, and three data disks.\nThe full-stripe width is 3072 sectors. For a one-sector write at array\nsector 3072, correct rounding gives array range [3072, 6144), which maps\nto component range [1024, 2048). The old round_down()/round_up() logic\ninstead gives [1024, 4096), which maps to [0, 1024).\n\nUse sector_div() based arithmetic so the rounded range is aligned to the\nactual RAID5 stripe width.\n\nThe deterministic mapper test now reports the fixed component range as\n[1024, 2048), while the old mask-based range was [0, 1024).","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/02c10581866d08822c6348e299881485fc546185","tags":[]},{"url":"https://git.kernel.org/stable/c/17ea021ae74987d6064c8195c4922fa025753892","tags":[]},{"url":"https://git.kernel.org/stable/c/9d7490007707f90691911385365bd1d691d99225","tags":[]},{"url":"https://git.kernel.org/stable/c/cab7d949b18b2f1cd625689dc16c5f81236bac93","tags":[]},{"url":"https://git.kernel.org/stable/c/ccbdc483eb041eef809e9ff223d1ad63518a2c52","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}