From: Martin Buck <mb-tmp-tvguho.pbz@gromit.dyndns.org>
Date: Fri, 29 Jan 2021 18:26:49 +0000 (+0100)
Subject: ospf6d: Fix LSA formatting inconsistent retvals
X-Git-Tag: base_8.0~419^2
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=8e04b88b8db4b6c154686c0d43ca192f041072b8;p=matthieu%2Ffrr.git

ospf6d: Fix LSA formatting inconsistent retvals

Make return values for lh_get_prefix_str LSA handlers consistent, i.e.
return NULL in case of error without having written to the passed buffer
and non-NULL (address of buffer) if a string was written to the buffer.

Previously, it was possible in certain cases (bogus LSAs) to not initialize
(and 0-terminate) the buffer but still return non-NULL, causing the caller
to print random junk.

Signed-off-by: Martin Buck <mb-tmp-tvguho.pbz@gromit.dyndns.org>
---

diff --git a/ospf6d/ospf6_intra.c b/ospf6d/ospf6_intra.c
index 01e4b31c4e..fd154e7ee5 100644
--- a/ospf6d/ospf6_intra.c
+++ b/ospf6d/ospf6_intra.c
@@ -84,12 +84,13 @@ static char *ospf6_router_lsa_get_nbr_id(struct ospf6_lsa *lsa, char *buf,
 				inet_ntop(AF_INET, &lsdesc->neighbor_router_id,
 					  buf2, sizeof(buf2));
 				sprintf(buf, "%s/%s", buf2, buf1);
+
+				return buf;
 			}
-		} else
-			return NULL;
+		}
 	}
 
-	return buf;
+	return NULL;
 }
 
 static int ospf6_router_lsa_show(struct vty *vty, struct ospf6_lsa *lsa,
@@ -444,14 +445,15 @@ static char *ospf6_network_lsa_get_ar_id(struct ospf6_lsa *lsa, char *buf,
 
 		if ((current + sizeof(struct ospf6_network_lsdesc)) <= end) {
 			lsdesc = (struct ospf6_network_lsdesc *)current;
-			if (buf)
+			if (buf) {
 				inet_ntop(AF_INET, &lsdesc->router_id, buf,
 					  buflen);
-		} else
-			return NULL;
+				return buf;
+			}
+		}
 	}
 
-	return (buf);
+	return NULL;
 }
 
 static int ospf6_network_lsa_show(struct vty *vty, struct ospf6_lsa *lsa,
@@ -901,7 +903,7 @@ static char *ospf6_intra_prefix_lsa_get_prefix_str(struct ospf6_lsa *lsa,
 			}
 		} while (current <= end);
 	}
-	return (buf);
+	return NULL;
 }
 
 static int ospf6_intra_prefix_lsa_show(struct vty *vty, struct ospf6_lsa *lsa,