autofs: fix a leak in autofs_expire_indirect()

BugLink: https://bugs.launchpad.net/bugs/1857158
[ Upstream commit 03ad0d703df75c43f78bd72e16124b5b94a95188 ]

if the second call of should_expire() in there ends up
grabbing and returning a new reference to dentry, we need
to drop it before continuing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index 141f9bc213a3dfb34341480d4c397072b6a80f37..94a0017c923b183d196abd3e095a89679cef822a 100644 (file)
--- a/fs/autofs4/expire.c
+++ b/fs/autofs4/expire.c
@@ -472,9 +472,10 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
                 */
                flags &= ~AUTOFS_EXP_LEAVES;
                found = should_expire(expired, mnt, timeout, how);
-               if (!found || found != expired)
-                       /* Something has changed, continue */
+               if (found != expired) { // something has changed, continue
+                       dput(found);
                        goto next;
+               }
 
                if (expired != dentry)
                        dput(dentry);