From: Phil Sutter <phil@nwl.cc>
Date: Thu, 24 Aug 2017 09:51:50 +0000 (+0200)
Subject: lib/ll_map: Choose size of new cache items at run-time
X-Git-Tag: v4.13.0~26
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4b9e91782269fc871d158ed4f11bfcfe4e3b8bf7;p=thirdparty%2Fiproute2.git

lib/ll_map: Choose size of new cache items at run-time

Instead of having a fixed buffer of 16 bytes for the interface name,
tailor size of new ll_cache entry using the interface name's actual
length. This also makes sure the following call to strcpy() is safe.

Signed-off-by: Phil Sutter <phil@nwl.cc>
---

diff --git a/lib/ll_map.c b/lib/ll_map.c
index 4e4556c9a..70684b020 100644
--- a/lib/ll_map.c
+++ b/lib/ll_map.c
@@ -30,7 +30,7 @@ struct ll_cache {
 	unsigned	flags;
 	unsigned 	index;
 	unsigned short	type;
-	char		name[IFNAMSIZ];
+	char		name[];
 };
 
 #define IDXMAP_SIZE	1024
@@ -120,7 +120,7 @@ int ll_remember_index(const struct sockaddr_nl *who,
 		return 0;
 	}
 
-	im = malloc(sizeof(*im));
+	im = malloc(sizeof(*im) + strlen(ifname) + 1);
 	if (im == NULL)
 		return 0;
 	im->index = ifi->ifi_index;