In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
lockd: pin next file across nlm_inspect_file lock-drop<\/p>\n
nlm_traverse_files() pins the current file with f_count++ across
\na mutex_unlock for nlm_inspect_file(), but nothing pins the saved
\nnext pointer. A concurrent nlm_release_file() can kfree the next
\nfile during the unlock window, and the iterator dereferences freed
\nmemory on the next loop step.<\/p>\n
Pin both current and next before the lock-drop. Advance by
\nswapping the pinned cursors at the end of each iteration so next
\nis always held alive across the unlock.<\/p>\n
Always call nlm_file_release() after dropping the iteration pin,
\nregardless of whether the file matched the predicate. Use
\nnlm_file_inuse(), which does a live walk of the inode lock list,
\nrather than the cached f_locks field, so skipped files that never
\nran nlm_inspect_file() are evaluated correctly.<\/p>\n
Because every file in a hash bucket is now pinned and released,
\nfiles skipped by the is_failover_file predicate that have no
\nlocks, blocks, shares, or external references are deleted during
\ntraversal. The old code never evaluated skipped files for
\ncleanup. The new behavior is intentional: such files are stale
\nand should not persist in the table.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
lockd: pin next file across nlm_inspect_file lock-drop<\/p>\n
nlm_traverse_files() pins the current file with f_count++ across
\na mutex_un<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21407","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21407","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=21407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}