diff --git a/libavcodec/iff.c b/libavcodec/iff.c
index e5a75bd617..7f8f868ba9 100644
--- a/libavcodec/iff.c
+++ b/libavcodec/iff.c
@@ -590,7 +590,7 @@ static void decode_deep_rle32(uint8_t *dst, const uint8_t *src, int src_size, in
 {
     const uint8_t *src_end = src + src_size;
     int x = 0, y = 0, i;
-    while (src + 5 <= src_end) {
+    while (src_end - src >= 5) {
         int opcode;
         opcode = *(int8_t *)src++;
         if (opcode >= 0) {