!5 Openssl CVE-2021-3449 漏洞bugfix

Merge pull request !5 from HJ/master

ssl/statem/extensions.c

@@ -1136,6 +1136,7 @@ static int init_sig_algs(SSL *s, unsigned int context)
     /* Clear any signature algorithms extension received */
     OPENSSL_free(s->s3->tmp.peer_sigalgs);
     s->s3->tmp.peer_sigalgs = NULL;
+    s->s3->tmp.peer_sigalgslen = 0;
 
     return 1;
 }