From: Andrea Claudi <aclaudi@redhat.com>
Date: Mon, 29 May 2023 21:42:16 +0000 (+0200)
Subject: iproute_lwtunnel: fix array boundary check
X-Git-Tag: v6.4.0~15
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1cf50a1f2723764eb53fad7c5ff8754835806df0;p=thirdparty%2Fiproute2.git

iproute_lwtunnel: fix array boundary check

seg6_mode_types is made up of 5 elements, so ARRAY_SIZE(seg6_mode_types)
evaluates to 5. Thus, when mode = 5, this function returns
seg6_mode_types[5], resulting in an out-of-bound access.

Fix this bailing out when mode is equal to or greater than 5.

Fixes: cf87da417bb4 ("iproute: add support for seg6 l2encap mode")
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

diff --git a/ip/iproute_lwtunnel.c b/ip/iproute_lwtunnel.c
index 96de3b207..949859723 100644
--- a/ip/iproute_lwtunnel.c
+++ b/ip/iproute_lwtunnel.c
@@ -140,7 +140,7 @@ static const char *seg6_mode_types[] = {
 
 static const char *format_seg6mode_type(int mode)
 {
-	if (mode < 0 || mode > ARRAY_SIZE(seg6_mode_types))
+	if (mode < 0 || mode >= ARRAY_SIZE(seg6_mode_types))
 		return "<unknown>";
 
 	return seg6_mode_types[mode];