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From: Pablo Neira Ayuso <pablo@netfilter.org>
To: netfilter-devel@vger.kernel.org
Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org,
	pabeni@redhat.com, edumazet@google.com, horms@kernel.org,
	fw@strlen.de, ja@ssi.bg
Subject: [PATCH net 02/10] netfilter: conncount: use DEBUG_NET_WARN_ON_ONCE on reaching count limit
Date: Fri, 21 Aug 2026 17:38:25 +0200	[thread overview]
Message-ID: <20260821153833.245589-3-pablo@netfilter.org> (raw)
In-Reply-To: <20260821153833.245589-1-pablo@netfilter.org>

From: Fernando Fernandez Mancera <fmancera@suse.de>

Replace WARN_ON_ONCE with DEBUG_NET_WARN_ON_ONCE in __nf_conncount_add.
The function handles count limit breaches safely by returning
-EOVERFLOW, so a production backtrace is not needed. This prevents
unnecessary system panics when panic_on_warn=1 is enabled in production
systems.

Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_conncount.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nf_conncount.c b/net/netfilter/nf_conncount.c
index 85487f92af50..4292c3d9addd 100644
--- a/net/netfilter/nf_conncount.c
+++ b/net/netfilter/nf_conncount.c
@@ -251,7 +251,8 @@ static int __nf_conncount_add(struct net *net,
 	list->last_gc_count = list->count;
 
 add_new_node:
-	if (WARN_ON_ONCE(list->count > INT_MAX)) {
+	if (unlikely(list->count > INT_MAX)) {
+		DEBUG_NET_WARN_ON_ONCE(1);
 		err = -EOVERFLOW;
 		goto out_put;
 	}
-- 
2.47.3


  parent reply	other threads:[~2026-08-21 15:38 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-21 15:38 [PATCH net 00/10] Netfilter fixes for net Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 01/10] netfilter: tproxy: use DEBUG_NET_WARN_ON_ONCE for protocol fallbacks Pablo Neira Ayuso
2026-08-21 15:38 ` Pablo Neira Ayuso [this message]
2026-08-21 15:38 ` [PATCH net 03/10] netfilter: nf_tables: move hardware offload step after building the chain blob Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 04/10] netfilter: nft_set_pipapo_avx2: add missing vzeroupper Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 05/10] netfilter: x_tables: remove pr_debug Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 06/10] netfilter: xt_cgroup: use pr_info_ratelimited() Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 07/10] netfilter: nf_tables: skip double clone set expressions on element insert Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 08/10] netfilter: nf_tables: fix device name and prefix match in hook lookup Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 09/10] netfilter: nf_tables: set on dead bit when performing early element removal Pablo Neira Ayuso
2026-08-21 15:38 ` [PATCH net 10/10] netfilter: nf_tables: remove leftover set_update_list Pablo Neira Ayuso

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