ensure no NULL is passed to memcpy

NULL is valid when size is 0, but memcpy uses nonnull attributes,
so let's not poke the bear

2 files changed, 4 insertions, 3 deletions

diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index a03a0989b..f05eb0f30 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -1077,11 +1077,11 @@ void BlockchainLMDB::add_tx_amount_output_indices(const uint64_t tx_id,
 
   int result = 0;
 
-  int num_outputs = amount_output_indices.size();
+  size_t num_outputs = amount_output_indices.size();
 
   MDB_val_set(k_tx_id, tx_id);
   MDB_val v;
-  v.mv_data = (void *)amount_output_indices.data();
+  v.mv_data = num_outputs ? (void *)amount_output_indices.data() : (void*)"";
   v.mv_size = sizeof(uint64_t) * num_outputs;
   // LOG_PRINT_L1("tx_outputs[tx_hash] size: " << v.mv_size);
 
diff --git a/src/crypto/keccak.c b/src/crypto/keccak.c
index 170911262..18ed3152f 100644
--- a/src/crypto/keccak.c
+++ b/src/crypto/keccak.c
@@ -116,7 +116,8 @@ void keccak(const uint8_t *in, size_t inlen, uint8_t *md, int mdlen)
       local_abort("Bad keccak use");
     }
 
-    memcpy(temp, in, inlen);
+    if (inlen > 0)
+      memcpy(temp, in, inlen);
     temp[inlen++] = 1;
     memset(temp + inlen, 0, rsiz - inlen);
     temp[rsiz - 1] |= 0x80;