rbd: avoid qemu_rbd_snap_list() memory leaks

When there are no snapshots qemu_rbd_snap_list() returns 0 and the
snapshot table pointer is NULL.  Don't forget to free the snaps buffer
we allocated for librbd rbd_snap_list().

When the function succeeds don't forget to free the snaps buffer after
calling rbd_snap_list_end().

Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 9e6337d0818650362149b734d53edf9489f3acaa)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/block/rbd.c b/block/rbd.c
index cb71751218298cc0dcba4e48cc5f1d10893b597e..7e7c735d753d0d66e9b5f5678bb5dbc625b138bb 100644 (file)
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -934,7 +934,7 @@ static int qemu_rbd_snap_list(BlockDriverState *bs,
     do {
         snaps = g_malloc(sizeof(*snaps) * max_snaps);
         snap_count = rbd_snap_list(s->image, snaps, &max_snaps);
-        if (snap_count < 0) {
+        if (snap_count <= 0) {
             g_free(snaps);
         }
     } while (snap_count == -ERANGE);
@@ -958,6 +958,7 @@ static int qemu_rbd_snap_list(BlockDriverState *bs,
         sn_info->vm_clock_nsec = 0;
     }
     rbd_snap_list_end(snaps);
+    g_free(snaps);
 
  done:
     *psn_tab = sn_tab;