From: Roy Marples <roy@marples.name>
Date: Sun, 21 Jun 2026 11:15:37 +0000 (+0100)
Subject: ARP: Iterate over states safely as the cb could remove ours
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=HEAD;p=thirdparty%2Fdhcpcd.git

ARP: Iterate over states safely as the cb could remove ours

Reported by NVIDIA Project Vanessa
---

diff --git a/src/arp.c b/src/arp.c
index 9c318be2..0e559a9e 100644
--- a/src/arp.c
+++ b/src/arp.c
@@ -477,7 +477,7 @@ arp_announce(struct arp_state *astate)
 {
 	struct iarp_state *state;
 	struct interface *ifp;
-	struct arp_state *a2;
+	struct arp_state *a2, *an;
 	int r;
 
 	/* Cancel any other ARP announcements for this address. */
@@ -485,7 +485,7 @@ arp_announce(struct arp_state *astate)
 		state = ARP_STATE(ifp);
 		if (state == NULL)
 			continue;
-		TAILQ_FOREACH(a2, &state->arp_states, next) {
+		TAILQ_FOREACH_SAFE(a2, &state->arp_states, next, an) {
 			if (astate == a2 ||
 			    a2->addr.s_addr != astate->addr.s_addr)
 				continue;