bdrv_img_create: Fix segfault

Block drivers that don't support creating images don't have a size option. Fail
gracefully instead of segfaulting when trying to access the option's value.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2011-06-01 14:03:31 +02:00
parent 80fa3341a7
commit d220894e02

View File

@ -2881,7 +2881,7 @@ int bdrv_img_create(const char *filename, const char *fmt,
char *options, uint64_t img_size, int flags)
{
QEMUOptionParameter *param = NULL, *create_options = NULL;
QEMUOptionParameter *backing_fmt, *backing_file;
QEMUOptionParameter *backing_fmt, *backing_file, *size;
BlockDriverState *bs = NULL;
BlockDriver *drv, *proto_drv;
BlockDriver *backing_drv = NULL;
@ -2964,7 +2964,8 @@ int bdrv_img_create(const char *filename, const char *fmt,
// The size for the image must always be specified, with one exception:
// If we are using a backing file, we can obtain the size from there
if (get_option_parameter(param, BLOCK_OPT_SIZE)->value.n == -1) {
size = get_option_parameter(param, BLOCK_OPT_SIZE);
if (size && size->value.n == -1) {
if (backing_file && backing_file->value.s) {
uint64_t size;
char buf[32];