From 640994b64a26ef45676266bc32799fe18ef3f9b1 Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Wed, 20 Mar 2019 17:32:44 +0000
Subject: [PATCH] fix a possible segv writing images to buffers

if write failed, vips_image_write_to_buffer() could segv

thanks @dbouron !

see https://github.com/libvips/libvips/issues/1248
---
 libvips/iofuncs/image.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libvips/iofuncs/image.c b/libvips/iofuncs/image.c
index 2116f222..fd80f0e0 100644
--- a/libvips/iofuncs/image.c
+++ b/libvips/iofuncs/image.c
@@ -2631,6 +2631,12 @@ vips_image_write_to_buffer( VipsImage *in,
 		ap, in, &blob );
 	va_end( ap );
 
+	if( result )
+		return( -1 );
+
+	*buf = NULL;
+	if( size ) 
+		*size = 0;
 	if( blob ) { 
 		if( buf ) {
 			*buf = VIPS_AREA( blob )->data;
@@ -2642,7 +2648,7 @@ vips_image_write_to_buffer( VipsImage *in,
 		vips_area_unref( VIPS_AREA( blob ) );
 	}
 
-	return( result );
+	return( 0 );
 }
 
 /**