From: Andrea Claudi <aclaudi@redhat.com>
Date: Sat, 7 Aug 2021 16:57:38 +0000 (+0200)
Subject: lib: bpf_legacy: fix potential NULL-pointer dereference
X-Git-Tag: v5.14.0~10
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=50a412702252ba29524b860df6c30d14f03cd34a;p=thirdparty%2Fiproute2.git

lib: bpf_legacy: fix potential NULL-pointer dereference

If bpf_map_fetch_name() returns NULL, strlen() hits a NULL-pointer
dereference on outer_map_name.

Fix this checking outer_map_name value, and returning false when NULL,
as already done for inner_map_name before.

Fixes: 6d61a2b55799 ("lib: add libbpf support")
Signed-off-by: Andrea Claudi <aclaudi@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

diff --git a/lib/bpf_legacy.c b/lib/bpf_legacy.c
index e8a41e6fb..91086aa20 100644
--- a/lib/bpf_legacy.c
+++ b/lib/bpf_legacy.c
@@ -3298,6 +3298,9 @@ bool iproute2_is_map_in_map(const char *libbpf_map_name, struct bpf_elf_map *ima
 
 			*omap = ctx->maps[j];
 			outer_map_name = bpf_map_fetch_name(ctx, j);
+			if (!outer_map_name)
+				return false;
+
 			memcpy(omap_name, outer_map_name, strlen(outer_map_name) + 1);
 
 			return true;