block/qcow.c: Fix memory leak in qcow_create()

Coverity points out that the code path in qcow_create() for
the magic "fat:" backing file name leaks the memory used to
store the filename (CID 1307771). Free the memory before
we overwrite the pointer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block/qcow.c b/block/qcow.c
index 95ab123407f1963a52d425c6d496165b31f21f52..7bd94dcd46b83f11eb12d5b1543dbd70127b0ced 100644 (file)
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -852,6 +852,7 @@ static int qcow_create(const char *filename, QemuOpts *opts, Error **errp)
             header_size += backing_filename_len;
         } else {
             /* special backing file for vvfat */
+            g_free(backing_file);
             backing_file = NULL;
         }
         header.cluster_bits = 9; /* 512 byte cluster to avoid copying