Use unsigned int for the length variable when traversing the others array.

Doing this in all places now after fixing an overflow in attr_optadd().

OK tb@ deraadt@

usr.sbin/bgpd/mrt.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: mrt.c,v 1.134 2026/02/17 14:06:44 claudio Exp $ */
+/*	$OpenBSD: mrt.c,v 1.135 2026/05/07 20:35:19 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Claudio Jeker <claudio@openbsd.org>
@@ -222,9 +222,10 @@ mrt_attr_dump(struct ibuf *buf, struct rde_aspath *a, struct rde_community *c,
 	struct attr	*oa;
 	u_char		*pdata;
 	uint32_t	 tmp;
+	unsigned int	 l;
 	int		 neednewpath = 0;
 	uint16_t	 plen, afi;
-	uint8_t		 l, safi;
+	uint8_t		 safi;
 
 	/* origin */
 	if (attr_writebuf(buf, ATTR_WELL_KNOWN, ATTR_ORIGIN,

usr.sbin/bgpd/rde.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde.c,v 1.696 2026/05/07 09:42:26 claudio Exp $ */
+/*	$OpenBSD: rde.c,v 1.697 2026/05/07 20:35:19 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -2923,7 +2923,7 @@ rde_dump_rib_as(struct prefix *p, struct rde_aspath *asp, pid_t pid, int flags)
 	struct rde_peer		*peer;
 	monotime_t		 staletime;
 	size_t			 aslen;
-	uint8_t			 l;
+	unsigned int		 l;
 
 	nexthop = prefix_nexthop(p);
 	peer = prefix_peer(p);
@@ -3041,7 +3041,7 @@ rde_dump_adjout_as(struct rde_peer *peer, struct pt_entry *pte,
 	struct rde_aspath	*asp;
 	struct nexthop		*nexthop;
 	size_t			 aslen;
-	uint8_t			 l;
+	unsigned int		 l;
 
 	nexthop = attrs->nexthop;
 	asp = attrs->aspath;

usr.sbin/bgpd/rde_attr.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_attr.c,v 1.143 2026/05/05 08:37:45 claudio Exp $ */
+/*	$OpenBSD: rde_attr.c,v 1.144 2026/05/07 20:35:19 claudio Exp $ */
 
 /*
  * Copyright (c) 2004 Claudio Jeker <claudio@openbsd.org>
@@ -152,7 +152,7 @@ attr_optadd(struct rde_aspath *asp, uint8_t flags, uint8_t type,
 struct attr *
 attr_optget(const struct rde_aspath *asp, uint8_t type)
 {
-	uint8_t l;
+	unsigned int l;
 
 	for (l = 0; l < asp->others_len; l++) {
 		if (asp->others[l] == NULL)
@@ -168,7 +168,7 @@ attr_optget(const struct rde_aspath *asp, uint8_t type)
 void
 attr_copy(struct rde_aspath *t, const struct rde_aspath *s)
 {
-	uint8_t l;
+	unsigned int l;
 
 	if (t->others != NULL)
 		attr_freeall(t);
@@ -208,22 +208,25 @@ attr_eq(const struct attr *oa, const struct attr *ob)
 int
 attr_equal(const struct rde_aspath *a, const struct rde_aspath *b)
 {
-	uint8_t l;
+	unsigned int l;
 
 	if (a->others_len != b->others_len)
 		return (0);
-	for (l = 0; l < a->others_len; l++)
+	for (l = 0; l < a->others_len; l++) {
 		if (a->others[l] != b->others[l])
 			return (0);
+		if (a->others[l] == NULL)
+			break;
+	}
 	return (1);
 }
 
 void
 attr_free(struct rde_aspath *asp, struct attr *attr)
 {
-	uint8_t l;
+	unsigned int l;
 
-	for (l = 0; l < asp->others_len; l++)
+	for (l = 0; l < asp->others_len; l++) {
 		if (asp->others[l] == attr) {
 			attr_put(asp->others[l]);
 			for (++l; l < asp->others_len; l++)
@@ -231,6 +234,9 @@ attr_free(struct rde_aspath *asp, struct attr *attr)
 			asp->others[asp->others_len - 1] = NULL;
 			return;
 		}
+		if (asp->others[l] == NULL)
+			break;
+	}
 
 	/* no realloc() because the slot may be reused soon */
 }
@@ -238,7 +244,7 @@ attr_free(struct rde_aspath *asp, struct attr *attr)
 void
 attr_freeall(struct rde_aspath *asp)
 {
-	uint8_t l;
+	unsigned int l;
 
 	for (l = 0; l < asp->others_len; l++)
 		attr_put(asp->others[l]);

usr.sbin/bgpd/rde_update.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_update.c,v 1.193 2026/02/11 10:24:57 claudio Exp $ */
+/*	$OpenBSD: rde_update.c,v 1.194 2026/05/07 20:35:19 claudio Exp $ */
 
 /*
  * Copyright (c) 2004 Claudio Jeker <claudio@openbsd.org>
@@ -591,9 +591,10 @@ up_generate_attr(struct ibuf *buf, struct rde_peer *peer,
 	struct attr	*oa = NULL, *newaggr = NULL;
 	u_char		*pdata;
 	uint32_t	 tmp32;
+	unsigned int	 oalen = 0;
 	int		 flags, neednewpath = 0, rv;
 	uint16_t	 plen;
-	uint8_t		 oalen = 0, type;
+	uint8_t		 type;
 
 	if (asp->others_len > 0)
 		oa = asp->others[oalen++];