[Qemu-stable] [PATCH 01/12] block: qcow2 driver may not be found

[Max Reitz]

Albeit absolutely impossible right now, bdrv_find_format("qcow2") may
fail. bdrv_append_temp_snapshot() should heed that case.

Cc: address@hidden
Signed-off-by: Max Reitz <address@hidden>
---
 block.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/block.c b/block.c
index 866c8b4..b31fb67 100644
--- a/block.c
+++ b/block.c
@@ -1320,6 +1320,12 @@ int bdrv_append_temp_snapshot(BlockDriverState *bs, int 
flags, Error **errp)
     }
 
     bdrv_qcow2 = bdrv_find_format("qcow2");
+    if (!bdrv_qcow2) {
+        error_setg(errp, "Failed to locate qcow2 driver");
+        ret = -ENOENT;
+        goto out;
+    }
+
     opts = qemu_opts_create(bdrv_qcow2->create_opts, NULL, 0,
                             &error_abort);
     qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size);
-- 
1.9.3