In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
btrfs: don’t propagate EXTENT_FLAG_LOGGING to split extent maps<\/p>\n
When btrfs_drop_extent_map_range() splits an extent map, the new split
\nmaps inherit the original map’s flags through a local ‘flags’ variable.
\nCommit f86f7a75e2fb (“btrfs: use the flags of an extent map to identify
\nthe compression type”) changed the EXTENT_FLAG_LOGGING clearing to
\noperate on em->flags instead of that local ‘flags’ copy, so a split of
\nan extent map that is currently being logged wrongly inherits
\nEXTENT_FLAG_LOGGING.<\/p>\n
The flag is then never cleared on the split, and when it is freed while
\nstill on the inode’s modified_extents list (for example by the extent
\nmap shrinker) it trips the WARN_ON(!list_empty(&em->list)) in
\nbtrfs_free_extent_map() and leads to a use-after-free.<\/p>\n
Clear EXTENT_FLAG_LOGGING from the local ‘flags’ copy used for the
\nsplits and only clear EXTENT_FLAG_PINNED from em->flags, restoring the
\nbehaviour prior to f86f7a75e2fb.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
btrfs: don’t propagate EXTENT_FLAG_LOGGING to split extent maps<\/p>\n
When btrfs_drop_extent_map_range() splits an extent map, the new s<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-6082","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/6082","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=6082"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6082"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6082"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}