usb: check USB configuration descriptor object

When processing remote NDIS control message packets, the USB Net device emulator checks to see if the USB configuration descriptor object is of RNDIS type(2). But it does not check if it is null, which leads to a null dereference error. Add check to avoid it. Reported-by: Qinghao Tang <[email protected]> Signed-off-by: Prasad J Pandit <[email protected]> Message-id: [email protected] Signed-off-by: Gerd Hoffmann <[email protected]>
colemickens · Feb 23, 2016 · 80eecda · 80eecda
1 parent 8eb779e
commit 80eecda
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/hw/usb/dev-network.c b/hw/usb/dev-network.c
@@ -654,7 +654,8 @@ typedef struct USBNetState {
 
 static int is_rndis(USBNetState *s)
 {
-    return s->dev.config->bConfigurationValue == DEV_RNDIS_CONFIG_VALUE;
+    return s->dev.config ?
+            s->dev.config->bConfigurationValue == DEV_RNDIS_CONFIG_VALUE : 0;
 }
 
 static int ndis_query(USBNetState *s, uint32_t oid,