From efe9da0994eb843c7d06055d4dd79b8624b0dff8 Mon Sep 17 00:00:00 2001
From: David Garske <david@wolfssl.com>
Date: Thu, 28 May 2020 07:57:56 -0700
Subject: [PATCH] Fix for STM32 crypto hash with `WOLFSSL_SMALL_STACK_CACHE`
 possible free of invalid pointer.

---
 wolfcrypt/src/sha256.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/wolfcrypt/src/sha256.c b/wolfcrypt/src/sha256.c
index eb0911b01..9ff35a90e 100644
--- a/wolfcrypt/src/sha256.c
+++ b/wolfcrypt/src/sha256.c
@@ -494,6 +494,7 @@ static int InitSha256(wc_Sha256* sha256)
         (void)devId;
         (void)heap;
 
+        XMEMSET(sha256, 0, sizeof(wc_Sha256));
         wc_Stm32_Hash_Init(&sha256->stmCtx);
         return 0;
     }