In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
md\/raid5: round bitmap stripes with sector division<\/p>\n
raid5_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.<\/p>\n
Reproduce 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).<\/p>\n
Use sector_div() based arithmetic so the rounded range is aligned to the
\nactual RAID5 stripe width.<\/p>\n
The deterministic mapper test now reports the fixed component range as
\n[1024, 2048), while the old mask-based range was [0, 1024).<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
md\/raid5: round bitmap stripes with sector division<\/p>\n
raid5_bitmap_sector_map() aligns the array range to full RAID5 stripe
\nwidths b<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25688","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25688","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=25688"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25688"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25688"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}