diff --git a/src/libsodium/sodium/codecs.c b/src/libsodium/sodium/codecs.c
index 9d82d03f..7e203a5c 100644
--- a/src/libsodium/sodium/codecs.c
+++ b/src/libsodium/sodium/codecs.c
@@ -86,6 +86,9 @@ sodium_hex2bin(unsigned char *const bin, const size_t bin_maxlen,
     if (hex_end != NULL) {
         *hex_end = &hex[hex_pos];
     }
+    if (ret != 0) {
+        bin_pos = (size_t) 0U;
+    }
     if (bin_len != NULL) {
         *bin_len = bin_pos;
     }
@@ -208,6 +211,7 @@ sodium_bin2base64(char * const b64, const size_t b64_maxlen,
             b64[b64_pos++] = (char) b64_byte_to_char((acc << (6 - acc_len)) & 0x3F);
         }
     }
+    assert(b64_pos <= b64_len);
     while (b64_pos < b64_len) {
         b64[b64_pos++] = '=';
     }
@@ -298,6 +302,9 @@ sodium_base642bin(unsigned char * const bin, const size_t bin_maxlen,
         ret = _sodium_base642bin_skip_padding(b64, b64_len, &b64_pos, ignore,
                                                acc_len / 2);
     }
+    if (ret != 0) {
+        bin_pos = (size_t) 0U;
+    }
     if (bin_len != NULL) {
         *bin_len = bin_pos;
     }
diff --git a/test/default/sodium_utils.c b/test/default/sodium_utils.c
index f0dee6bc..09c22544 100644
--- a/test/default/sodium_utils.c
+++ b/test/default/sodium_utils.c
@@ -117,8 +117,8 @@ main(void)
 
     b64 = "VGhpcyBpcyBhIGpvdXJu" "\n" "ZXkgaW50by" " " "Bzb3VuZA==";
     memset(buf4, '*', sizeof buf4);
-    sodium_base642bin(buf4, sizeof buf4, b64, strlen(b64), "\n\r ", &bin_len,
-                      &b64_end, sodium_base64_VARIANT_ORIGINAL);
+    assert(sodium_base642bin(buf4, sizeof buf4, b64, strlen(b64), "\n\r ", &bin_len,
+                             &b64_end, sodium_base64_VARIANT_ORIGINAL) == -1);
     buf4[bin_len] = 0;
     printf("[%s]\n", (const char *) buf4);
     printf("[%s]\n", b64_end);
diff --git a/test/default/sodium_utils.exp b/test/default/sodium_utils.exp
index f7c9f5d7..233dc687 100644
--- a/test/default/sodium_utils.exp
+++ b/test/default/sodium_utils.exp
@@ -23,7 +23,7 @@ YWJj
 YQ
 YWI
 YWJj
-[This]
+[]
 [BpcyBhIGpvdXJu
 ZXkgaW50by Bzb3VuZA==]
 [This is a journey into sound]