Fix some memory errors triggered by allocation failures (#1995)

Some low hanging fruits found using nallocfuzz.
See: https://github.com/catenacyber/nallocfuzz
See: https://github.com/google/oss-fuzz/pull/9902

Most of these errors are quite trivial to fix; the only exception is the
stuff in the uthash.
If the insertion fails (because of an allocation failure), we need to
avoid some memory leaks. But the only way to check if the `HASH_ADD_*`
failed, is to perform a new lookup: a bit costly, but we don't use that
code in any critical data-path.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/lib/ndpi_utils.c b/src/lib/ndpi_utils.c
index dfdca923a..0199d6424 100644
--- a/src/lib/ndpi_utils.c
+++ b/src/lib/ndpi_utils.c
@@ -2288,6 +2288,7 @@ int ndpi_hash_add_entry(ndpi_str_hash **h, char *key, u_int8_t key_len, void *va
 {
   struct ndpi_str_hash_private **h_priv = (struct ndpi_str_hash_private **)h;
   struct ndpi_str_hash_private *new = ndpi_calloc(1, sizeof(*new));
+  struct ndpi_str_hash_private *found;
   unsigned int hash_value;
 
   if (new == NULL)
@@ -2299,6 +2300,14 @@ int ndpi_hash_add_entry(ndpi_str_hash **h, char *key, u_int8_t key_len, void *va
   new->hash = hash_value;
   new->value = value;
   HASH_ADD_INT(*h_priv, hash, new);
+
+  HASH_FIND_INT(*h_priv, &hash_value, found);
+  if (found == NULL) /* The insertion failed (because of a memory allocation error) */
+  {
+    ndpi_free(new);
+    return 1;
+  }
+
   return 0;
 }