From: Dr. David von Oheimb <David.von.Oheimb@siemens.com>
Date: Sat, 12 Jun 2021 09:27:28 +0000 (+0200)
Subject: BIO: prevent crash on NULL BIO for prefix_ctrl() and thus for BIO_set_prefix(), BIO_s... 
X-Git-Tag: openssl-3.0.0-beta1~54
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9d9691f78a67fed1b30b0cf84b2f3601897b9639;p=thirdparty%2Fopenssl.git

BIO: prevent crash on NULL BIO for prefix_ctrl() and thus for BIO_set_prefix(), BIO_set_indent(), etc.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15722)
---

diff --git a/crypto/bio/bf_prefix.c b/crypto/bio/bf_prefix.c
index 5727c14950e..c9059ca80ae 100644
--- a/crypto/bio/bf_prefix.c
+++ b/crypto/bio/bf_prefix.c
@@ -151,9 +151,9 @@ static int prefix_write(BIO *b, const char *out, size_t outl,
 static long prefix_ctrl(BIO *b, int cmd, long num, void *ptr)
 {
     long ret = 0;
-    PREFIX_CTX *ctx = BIO_get_data(b);
+    PREFIX_CTX *ctx;
 
-    if (ctx == NULL)
+    if (b == NULL || (ctx = BIO_get_data(b)) == NULL)
         return -1;
 
     switch (cmd) {