From 3843f917e9873b80ff2a68bde38be93708a92d76 Mon Sep 17 00:00:00 2001
From: Andrew Kozlik <andrew.kozlik@gmail.com>
Date: Tue, 14 Apr 2020 17:03:40 +0200
Subject: [PATCH] crypto: Check for invalid characters in Monero Base58 decode.

---
 crypto/monero/base58.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/crypto/monero/base58.c b/crypto/monero/base58.c
index 44da376e9..ec6c4d779 100644
--- a/crypto/monero/base58.c
+++ b/crypto/monero/base58.c
@@ -102,6 +102,8 @@ bool decode_block(const char* block, size_t size, char* res)
 	uint64_t order = 1;
 	for (size_t i = size - 1; i < size; --i)
 	{
+		if (block[i] & 0x80)
+			return false; // Invalid symbol
 		int digit = reverse_alphabet(block[i]);
 		if (digit < 0)
 			return false; // Invalid symbol