From 8375db082c6b486b05cd8072979d113512341fab Mon Sep 17 00:00:00 2001
From: Michael Tuexen <tuexen@FreeBSD.org>
Date: Mon, 1 Apr 2024 21:51:59 +0200
Subject: [PATCH] tcp hpts: improve consistency

The target_slot argument of max_slots_available() can be NULL.
Therefore, check for this in all places.
Right now, all callers provide non-NULL pointer.

Reported by:		Coverity Scan
CID:			1527732
Reviewed by:		rrs
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D44527

(cherry picked from commit b600644fdd6cefb1b90d76fdd5aa595946611a7d)
---
 sys/netinet/tcp_hpts.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/netinet/tcp_hpts.c b/sys/netinet/tcp_hpts.c
index 9d192b17c41..89b9611e643 100644
--- a/sys/netinet/tcp_hpts.c
+++ b/sys/netinet/tcp_hpts.c
@@ -758,7 +758,8 @@ max_slots_available(struct tcp_hpts_entry *hpts, uint32_t wheel_slot, uint32_t *
 		 * "0".
 		 */
 		counter_u64_add(combined_wheel_wrap, 1);
-		*target_slot = hpts->p_nxt_slot;
+		if (target_slot)
+			*target_slot = hpts->p_nxt_slot;
 		return (0);
 	} else {
 		/*