[Qemu-devel] [PULL 09/34] block: An empty filename counts as no filename

[Kevin Wolf]

From: Max Reitz <mre...@redhat.com>

Reproducer:
    $ ./qemu-img info ''
    qemu-img: ./block.c:1008: bdrv_open_driver: Assertion
        `!drv->bdrv_needs_filename || bs->filename[0]' failed.
    [1]    26105 abort (core dumped)  ./qemu-img info ''

This patch fixes this to be:
    $ ./qemu-img info ''
    qemu-img: Could not open '': The 'file' block driver requires a file
    name

Cc: qemu-stable <qemu-sta...@nongnu.org>
Signed-off-by: Max Reitz <mre...@redhat.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
Reviewed-by: Fam Zheng <f...@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
Signed-off-by: Kevin Wolf <kw...@redhat.com>
---
 block.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block.c b/block.c
index ceaca44..7b557f3 100644
--- a/block.c
+++ b/block.c
@@ -1204,7 +1204,7 @@ static int bdrv_open_common(BlockDriverState *bs, 
BlockBackend *file,
         filename = qdict_get_try_str(options, "filename");
     }
 
-    if (drv->bdrv_needs_filename && !filename) {
+    if (drv->bdrv_needs_filename && (!filename || !filename[0])) {
         error_setg(errp, "The '%s' block driver requires a file name",
                    drv->format_name);
         ret = -EINVAL;
-- 
1.8.3.1