From 2708a5b39972c605fd84849fa8e4d46b52f7c561 Mon Sep 17 00:00:00 2001
From: dmiller <dmiller@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Mon, 29 Aug 2022 17:11:27 +0000
Subject: [PATCH] Avoid realloc leak

---
 libdnet-stripped/src/intf-win32.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/libdnet-stripped/src/intf-win32.c b/libdnet-stripped/src/intf-win32.c
index 599d7cf83..157595aa6 100644
--- a/libdnet-stripped/src/intf-win32.c
+++ b/libdnet-stripped/src/intf-win32.c
@@ -92,15 +92,23 @@ _ifcombo_type(const char *device)
 static void
 _ifcombo_add(struct ifcombo *ifc, DWORD ipv4_idx, DWORD ipv6_idx)
 {
+	void* pmem = NULL;
 	if (ifc->cnt == ifc->max) {
 		if (ifc->idx) {
 			ifc->max *= 2;
-			ifc->idx = realloc(ifc->idx,
+			pmem = realloc(ifc->idx,
 			    sizeof(ifc->idx[0]) * ifc->max);
 		} else {
 			ifc->max = 8;
-			ifc->idx = malloc(sizeof(ifc->idx[0]) * ifc->max);
+			pmem = malloc(sizeof(ifc->idx[0]) * ifc->max);
 		}
+		if (!pmem) {
+			/* malloc or realloc failed. Restore state.
+			 * TODO: notify caller. */
+			ifc->max = ifc->cnt;
+			return;
+		}
+		ifc->idx = pmem;
 	}
 	ifc->idx[ifc->cnt].ipv4 = ipv4_idx;
 	ifc->idx[ifc->cnt].ipv6 = ipv6_idx;