[Qemu-devel] [RESEND PATCH v2 2/3] exec.c: check memory backend file size with 'size' option

[Haozhong Zhang <haozhong.zhang@intel.com>]

If the memory backend file is not large enough to hold the required 'size',
Qemu will report error and exit.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Message-Id: <20161027042300.5929-3-haozhong.zhang@intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
---
Changes in RESEND:
* Use format string RAM_ADDR_FMT for variable 'memory'.
  This change is to fix the build error.
* Add Eduardo's r-b.
* Add the message id of this thread.
---
 exec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/exec.c b/exec.c
index a2b371a..23c21c2 100644
--- a/exec.c
+++ b/exec.c
@@ -1316,6 +1316,13 @@ static void *file_ram_alloc(RAMBlock *block,
         goto error;
     }
 
+    if (file_size > 0 && file_size < memory) {
+        error_setg(errp, "backing store %s size 0x%" PRIx64
+                   " does not match 'size' option 0x" RAM_ADDR_FMT,
+                   path, file_size, memory);
+        goto error;
+    }
+
     memory = ROUND_UP(memory, block->page_size);
 
     /*
-- 
2.10.1