commit cba0363734ed7319728d8219f00bdda543709521
from: Stefan Sperling <stsp@stsp.name>
date: Thu Aug 29 13:01:46 2024 UTC

in growwgdata, preserve original pointer during realloc for freeing on error

found by codechecker

commit - fd571e3ef4998485f4c5e94aa4615138c013dd49
commit + cba0363734ed7319728d8219f00bdda543709521
blob - a2db9c9270a72258e1c86dbc5dd540db5df5139d
blob + aa7eec25d1c7260b8c8851d7fd692918333b0e50
--- wg.c
+++ wg.c
@@ -87,6 +87,7 @@ int
 growwgdata(size_t by)
 {
 	ptrdiff_t peer_offset, aip_offset;
+	struct wg_interface_io	*p;
 
 	if (wg_interface == NULL)
 		wgdata.wgd_size = sizeof(*wg_interface);
@@ -95,11 +96,12 @@ growwgdata(size_t by)
 	aip_offset = (void *)wg_aip - (void *)wg_interface;
 
 	wgdata.wgd_size += by;
-	wgdata.wgd_interface = realloc(wg_interface, wgdata.wgd_size);
-	if (wgdata.wgd_interface == NULL) {
+	p = realloc(wg_interface, wgdata.wgd_size);
+	if (p == NULL) {
 		printf("%% growwgdata: realloc: %s\n", strerror(errno));
 		return(-1);
 	}
+	wgdata.wgd_interface = p;
 	if (wg_interface == NULL)
 		bzero(wgdata.wgd_interface, sizeof(*wg_interface));
 	wg_interface = wgdata.wgd_interface;