[PATCH 4.19 11/92] btrfs: ref-verify: fix memory leak in add_block_entry

[Greg Kroah-Hartman]

From: Tom Rix <t...@redhat.com>

commit d60ba8de1164e1b42e296ff270c622a070ef8fe7 upstream.

clang static analysis flags this error

fs/btrfs/ref-verify.c:290:3: warning: Potential leak of memory pointed to by 
're' [unix.Malloc]
                kfree(be);
                ^~~~~

The problem is in this block of code:

        if (root_objectid) {
                struct root_entry *exist_re;

                exist_re = insert_root_entry(&exist->roots, re);
                if (exist_re)
                        kfree(re);
        }

There is no 'else' block freeing when root_objectid is 0. Add the
missing kfree to the else branch.

Fixes: fd708b81d972 ("Btrfs: add a extent ref verify tool")
CC: sta...@vger.kernel.org # 4.19+
Signed-off-by: Tom Rix <t...@redhat.com>
Reviewed-by: David Sterba <dste...@suse.com>
Signed-off-by: David Sterba <dste...@suse.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 fs/btrfs/ref-verify.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/btrfs/ref-verify.c
+++ b/fs/btrfs/ref-verify.c
@@ -297,6 +297,8 @@ static struct block_entry *add_block_ent
                        exist_re = insert_root_entry(&exist->roots, re);
                        if (exist_re)
                                kfree(re);
+               } else {
+                       kfree(re);
                }
                kfree(be);
                return exist;