diff --git a/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c b/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
index 70a6ca3e..5382cbae 100644
--- a/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
+++ b/src/libsodium/crypto_generichash/blake2/ref/generichash_blake2b.c
@@ -14,7 +14,7 @@ crypto_generichash_blake2b(unsigned char *out, const unsigned char *in,
                            size_t keylen)
 {
     if (outlen <= 0U || outlen > BLAKE2B_OUTBYTES ||
-        keylen <= 0U || keylen > BLAKE2B_KEYBYTES ||
+        keylen > BLAKE2B_KEYBYTES ||
         inlen > UINT64_MAX) {
         return -1;
     }