Checking for pointer values after malloc and realloc

gaussian_blur/gblur.c

@@ -136,6 +136,10 @@ int8_t gaussian_blur(struct image_data * original_image, struct image_data * blu
     size_t num_channels = original_image->num_channels;
 
     tmp = (JSAMPROW)malloc(x * num_channels);
+    if (tmp == NULL) {
+        return 1;
+    }
+
     for (int j = 0; j < y; ++j) {
         for (int i = 0; i < x; ++i) {
             double sum = 0;
@@ -173,7 +177,12 @@ int8_t gaussian_blur(struct image_data * original_image, struct image_data * blu
         }
     }
 
-    tmp = realloc(tmp, y * num_channels);
+    JSAMPROW t = realloc(tmp, y * num_channels);
+    if (t == NULL) {
+        free(tmp);
+    } else {
+        tmp = t;
+    }
 
 //    Vertical box blur
     for (int i = 0; i < x; ++i) {