[Qemu-devel] [PATCH V5 2/6] qemu-img: Add infinite loop checking in bdrv_new_open()

[Xu Wang <gesaint@linux.vnet.ibm.com>]

From: Xu Wang <cngesaint@gmail.com>

Every image should be checked if there is infinite loop in backing
file chain before open it. So infinite loop check was added into
bdrv_new_open(). If @filename is opened with no flags
BDRV_O_NO_BACKING, the infinite loop check should be called.

Signed-off-by: Xu Wang <cngesaint@gmail.com>
---
 qemu-img.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/qemu-img.c b/qemu-img.c
index 4f01b0a..1a63bbf 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -278,6 +278,13 @@ static BlockDriverState *bdrv_new_open(const char *filename,
         drv = NULL;
     }
 
+    /* check backing file loop if the whole chain need to be opened */
+    if (!(flags & BDRV_O_NO_BACKING) &&
+        bdrv_backing_file_loop_check(filename, fmt, NULL, NULL)) {
+        error_report("bdrv_new_open: Open %s failed.", filename);
+        goto fail;
+    }
+
     ret = bdrv_open(bs, filename, NULL, flags, drv);
     if (ret < 0) {
         error_report("Could not open '%s': %s", filename, strerror(-ret));
-- 
1.8.1.4