scan-build: fix potential 0 size allocation warnings

src/detect-flowbits.c

@@ -111,6 +111,10 @@ static int FlowbitOrAddData(DetectEngineCtx *de_ctx, DetectFlowbitsData *cd, cha
     next:
         arrptr = NULL;
     }
+    if (i == 0) {
+        SCLogError("No valid flowbits specified");
+        return -1;
+    }
 
     cd->or_list_size = i;
     cd->or_list = SCCalloc(cd->or_list_size, sizeof(uint32_t));

src/util-pool.c

@@ -101,6 +101,10 @@ Pool *PoolInit(uint32_t size, uint32_t prealloc_size, uint32_t elt_size,
         sc_errno = SC_EINVAL;
         goto error;
     }
+    if (elt_size == 0 && Alloc == NULL) {
+        sc_errno = SC_EINVAL;
+        goto error;
+    }
 
     /* setup the filter */
     p = SCMalloc(sizeof(Pool));

src/util-radix-tree.c

@@ -133,7 +133,7 @@ static SCRadixPrefix *SCRadixCreatePrefix(uint8_t *key_stream,
 {
     SCRadixPrefix *prefix = NULL;
 
-    if ((key_bitlen % 8 != 0)) {
+    if (key_bitlen == 0 || (key_bitlen % 8 != 0)) {
         SCLogError("Invalid argument bitlen - %d", key_bitlen);
         return NULL;
     }