[driver] Avoid disabling disks that have already been enabled

Signed-off-by: Michael Brown <mbrown@fensystems.co.uk>
ipxe · Oct 9, 2011 · 3f33a9e · 3f33a9e
1 parent 4fb36fc
commit 3f33a9e
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/src/driver/sanbootconf.c b/src/driver/sanbootconf.c
@@ -313,7 +313,13 @@ static NTSTATUS check_system_disk ( PUNICODE_STRING name,
 
 	/* Enable interface if not already done */
 	status = IoSetDeviceInterfaceState ( name, TRUE );
-	must_disable = ( NT_SUCCESS ( status ) ? TRUE : FALSE );
+	/* If interface is already enabled, IoSetDeviceInterfaceState
+	 * will return STATUS_OBJECT_NAME_EXISTS, which counts as a
+	 * success status.
+	 */
+	must_disable = ( ( NT_SUCCESS ( status ) &&
+			   ( status != STATUS_OBJECT_NAME_EXISTS ) )
+			 ? TRUE : FALSE );
 
 	/* Get device and file object pointers */
 	status = IoGetDeviceObjectPointer ( name, FILE_ALL_ACCESS, &file,