jbd2: fix use after free in jbd2_journal_start_reserved()

If start_this_handle() fails then it leads to a use after free of
"handle".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 8360674c85bc..60bb365f54a5 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -514,11 +514,13 @@ int jbd2_journal_start_reserved(handle_t *handle, unsigned int type,
          * similarly constrained call sites
          */
         ret = start_this_handle(journal, handle, GFP_NOFS);
-        if (ret < 0)
+        if (ret < 0) {
                 jbd2_journal_free_reserved(handle);
+                return ret;
+        }
         handle->h_type = type;
         handle->h_line_no = line_no;
-        return ret;
+        return 0;
 }
 EXPORT_SYMBOL(jbd2_journal_start_reserved);