From 930e1ac4737906b9444e7f9c7578adfbc805a9aa Mon Sep 17 00:00:00 2001
From: Kareem <kareem@wolfssl.com>
Date: Wed, 17 Nov 2021 13:54:02 -0700
Subject: [PATCH] Check ssl->arrays in SendClientHello to avoid null
 dereference.  Allow building with fallthrough defined.

---
 src/internal.c            | 4 ++++
 wolfssl/wolfcrypt/types.h | 3 ++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/internal.c b/src/internal.c
index aca6eff7a..16d112d81 100644
--- a/src/internal.c
+++ b/src/internal.c
@@ -22666,6 +22666,10 @@ exit_dpk:
         WOLFSSL_START(WC_FUNC_CLIENT_HELLO_SEND);
         WOLFSSL_ENTER("SendClientHello");
 
+        if (ssl == NULL || ssl->arrays == NULL) {
+            return BAD_FUNC_ARG;
+        }
+
         if (ssl->suites == NULL) {
             WOLFSSL_MSG("Bad suites pointer in SendClientHello");
             return SUITES_ERROR;
diff --git a/wolfssl/wolfcrypt/types.h b/wolfssl/wolfcrypt/types.h
index 6b6b544fd..4bcf24a9d 100644
--- a/wolfssl/wolfcrypt/types.h
+++ b/wolfssl/wolfcrypt/types.h
@@ -315,7 +315,8 @@ decouple library dependencies with standard string, memory and so on.
                 #if defined(WOLFSSL_LINUXKM) && defined(fallthrough)
                     #define FALL_THROUGH fallthrough
                 #else
-                    #define FALL_THROUGH ; __attribute__ ((fallthrough))
+                    /* Use __ notation to avoid conflicts */
+                    #define FALL_THROUGH ; __attribute__ ((__fallthrough__))
                 #endif
             #endif
         #endif