diff --git a/media/libstagefright/MediaExtractor.cpp b/media/libstagefright/MediaExtractor.cpp
index a8019ee..47fd698 100644
--- a/media/libstagefright/MediaExtractor.cpp
+++ b/media/libstagefright/MediaExtractor.cpp
@@ -59,7 +59,7 @@
     }
 
     if (!strncmp(mime, "drm", 3)) {
-        char *originalMime = strrchr(mime, '+') + 1;
+        const char *originalMime = strrchr(mime, '+') + 1;
 
         if (!strncmp(mime, "drm+es_based", 12)) {
             return new DRMExtractor(source, originalMime);