From 250246fef22b87a54a63211c60a2def9be431fbd Mon Sep 17 00:00:00 2001
From: "markus@openbsd.org" <markus@openbsd.org>
Date: Wed, 24 Jun 2020 15:09:53 +0000
Subject: [PATCH] upstream: support loading big sshd_config files w/o realloc;
 ok

djm

OpenBSD-Commit-ID: ba9238e810074ac907f0cf8cee1737ac04983171
---
 servconf.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/servconf.c b/servconf.c
index bd8df7fce..22cb9583f 100644
--- a/servconf.c
+++ b/servconf.c
@@ -1,5 +1,5 @@
 
-/* $OpenBSD: servconf.c,v 1.365 2020/05/27 22:37:53 djm Exp $ */
+/* $OpenBSD: servconf.c,v 1.366 2020/06/24 15:09:53 markus Exp $ */
 /*
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
  *                    All rights reserved
@@ -15,6 +15,7 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/stat.h>
 #ifdef __OpenBSD__
 #include <sys/sysctl.h>
 #endif
@@ -2395,6 +2396,7 @@ process_server_config_line(ServerOptions *options, char *line,
 void
 load_server_config(const char *filename, struct sshbuf *conf)
 {
+	struct stat st;
 	char *line = NULL, *cp;
 	size_t linesize = 0;
 	FILE *f;
@@ -2406,6 +2408,10 @@ load_server_config(const char *filename, struct sshbuf *conf)
 		exit(1);
 	}
 	sshbuf_reset(conf);
+	/* grow buffer, so realloc is avoided for large config files */
+	if (fstat(fileno(f), &st) == 0 && st.st_size > 0 &&
+            (r = sshbuf_allocate(conf, st.st_size)) != 0)
+		fatal("%s: allocate failed: %s", __func__, ssh_err(r));
 	while (getline(&line, &linesize, f) != -1) {
 		lineno++;
 		/*