The qemu-img sub-command executes regardless of invalid global options:

  $ qemu-img --foo info test.img
  qemu-img: unrecognized option '--foo'
  image: test.img
  ...

The unrecognized option warning may be missed by the user.  This can
hide incorrect command-lines in scripts and confuse users.

This patch prints the help information and terminates instead of
executing the sub-command.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qemu-img.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/qemu-img.c b/qemu-img.c
index 98b836b..ce293a4 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -4339,6 +4339,7 @@ int main(int argc, char **argv)
     while ((c = getopt_long(argc, argv, "+hVT:", long_options, NULL)) != -1) {
         switch (c) {
         case 'h':
+        case '?':
             help();
             return 0;
         case 'V':
-- 
2.9.3