In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
NFSD: Release the export reference when reaping open stateids<\/p>\n
nfs4_put_stid() releases the svc_export tracked in
\nnfs4_stid.sc_export, but free_ol_stateid_reaplist() frees open and
\nlock stateids by calling ->sc_free() directly, bypassing that path.
\nAn open stateid takes an sc_export reference in nfs4_open() and a
\nlock stateid takes its own in init_lock_stateid(); both reach
\nfree_ol_stateid_reaplist() through their normal teardown, the open
\nstateid via release_open_stateid() and the lock stateid via
\nnfsd4_release_lockowner(), each through put_ol_stateid_locked().
\nThe reference is therefore never dropped, pinning the export and
\nblocking unmount for the lifetime of the stateid.<\/p>\n
Release sc_export in free_ol_stateid_reaplist() the way
\nnfs4_put_stid() does. ->sc_free() runs once per stateid, and a
\nstateid reaches free_ol_stateid_reaplist() or nfs4_put_stid() but
\nnever both, so the reference is dropped exactly once. Revoked
\nstateids reach this path with sc_export already cleared by
\ndrop_stid_export(), so they are skipped rather than double-freed.<\/p>\n
nfs4_put_stid() itself read sc_export before acquiring cl_lock.
\ndrop_stid_export() clears that field and releases the reference
\nunder cl_lock, so a concurrent revocation could drop the export in
\nthe window between the read and the final put, releasing the same
\nreference twice. Read sc_export while cl_lock is held so the two
\npaths serialize and the reference is released exactly once.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
NFSD: Release the export reference when reaping open stateids<\/p>\n
nfs4_put_stid() releases the svc_export tracked in
\nnfs4_stid.sc_expo<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25645","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25645","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=25645"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25645"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25645"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}