From: Maria Matejka <mq@ucw.cz>
Date: Fri, 16 Aug 2019 10:47:13 +0000 (+0200)
Subject: OSPF: variable-length array of size 0 replaced by alloca()'d pointer
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3c1ac361265cc212f19eae66454c8ead19b64602;p=thirdparty%2Fbird.git

OSPF: variable-length array of size 0 replaced by alloca()'d pointer

NULL pointer is safer than a random pointer onto stack if this function
gets changed and eventually broken.
---

diff --git a/proto/ospf/ospf.c b/proto/ospf/ospf.c
index 29610f4ac..3cb402834 100644
--- a/proto/ospf/ospf.c
+++ b/proto/ospf/ospf.c
@@ -1244,7 +1244,7 @@ ospf_sh_state(struct proto *P, int verbose, int reachable)
 
   uint num = p->gr->hash_entries;
   struct top_hash_entry *hea[num];
-  struct top_hash_entry *hex[verbose ? num : 0];
+  struct top_hash_entry **hex = verbose ? alloca(num * sizeof(struct top_hash_entry *)) : NULL;
   struct top_hash_entry *he;
   struct top_hash_entry *cnode = NULL;
 
@@ -1289,7 +1289,9 @@ ospf_sh_state(struct proto *P, int verbose, int reachable)
 
   lsa_compare_ospf3 = !ospf2;
   qsort(hea, j1, sizeof(struct top_hash_entry *), lsa_compare_for_state);
-  qsort(hex, jx, sizeof(struct top_hash_entry *), ext_compare_for_state);
+
+  if (verbose)
+    qsort(hex, jx, sizeof(struct top_hash_entry *), ext_compare_for_state);
 
   /*
    * This code is a bit tricky, we have a primary LSAs (router and