Signed-off-by: Markus Armbruster <arm...@redhat.com>
---
block.c | 45 ++++++++++++++++++++++++++++++++-------------
1 file changed, 32 insertions(+), 13 deletions(-)
diff --git a/block.c b/block.c
index 88f6d9b..8da6e61 100644
--- a/block.c
+++ b/block.c
@@ -644,11 +644,40 @@ BlockDriver *bdrv_find_protocol(const char *filename,
return NULL;
}
+/*
+ * Guess image format by probing its contents.
+ * This is not a good idea when your image is raw (CVE-2008-2004), but
+ * we do it anyway for backward compatibility.
+ * @buf contains the image's first @buf_size bytes.
+ * @buf_size is 2048 or the image's size, whatever is smaller.
+ * @filename is its filename.
+ * For all block drivers, call the bdrv_probe() method to get its
+ * probing score.
+ * Return the first block driver with the highest probing score.
+ */
+static BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
+ const char *filename)
+{
+ int score_max = 0, score;
+ BlockDriver *drv = NULL, *d;
+
+ QLIST_FOREACH(d, &bdrv_drivers, list) {
+ if (d->bdrv_probe) {
+ score = d->bdrv_probe(buf, buf_size, filename);
+ if (score > score_max) {
+ score_max = score;
+ drv = d;
+ }
+ }
+ }
+
+ return drv;
+}
+
static int find_image_format(BlockDriverState *bs, const char *filename,
BlockDriver **pdrv, Error **errp)
{
- int score, score_max;
- BlockDriver *drv1, *drv;
+ BlockDriver *drv;
uint8_t buf[2048];
int ret = 0;
@@ -671,17 +700,7 @@ static int find_image_format(BlockDriverState *bs, const
char *filename,
return ret;
}
- score_max = 0;
- drv = NULL;
- QLIST_FOREACH(drv1, &bdrv_drivers, list) {
- if (drv1->bdrv_probe) {
- score = drv1->bdrv_probe(buf, ret, filename);
- if (score > score_max) {
- score_max = score;
- drv = drv1;
- }
- }
- }
+ drv = bdrv_probe_all(buf, ret, filename);
if (!drv) {
error_setg(errp, "Could not determine image format: No compatible "
"driver found");
--
1.9.3
