[PULL 1/3] block/amend: Check whether the node exists

[Max Reitz <mreitz@redhat.com>]

We should check whether the user-specified node-name actually refers to
a node.  The simplest way to do that is to use bdrv_lookup_bs() instead
of bdrv_find_node() (the former wraps the latter, and produces an error
message if necessary).

Reported-by: Coverity (CID 1430268)
Fixes: ced914d0ab9fb2c900f873f6349a0b8eecd1fdbe
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200710095037.10885-1-mreitz@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 block/amend.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/amend.c b/block/amend.c
index f4612dcf08..392df9ef83 100644
--- a/block/amend.c
+++ b/block/amend.c
@@ -69,8 +69,12 @@ void qmp_x_blockdev_amend(const char *job_id,
     BlockdevAmendJob *s;
     const char *fmt = BlockdevDriver_str(options->driver);
     BlockDriver *drv = bdrv_find_format(fmt);
-    BlockDriverState *bs = bdrv_find_node(node_name);
+    BlockDriverState *bs;
 
+    bs = bdrv_lookup_bs(NULL, node_name, errp);
+    if (!bs) {
+        return;
+    }
 
     if (!drv) {
         error_setg(errp, "Block driver '%s' not found or not supported", fmt);
-- 
2.26.2