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From: Florian Westphal <fw@strlen.de>
To: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: netfilter-devel@vger.kernel.org
Subject: Followup needed for netfilter: nft_fib_ipv6: walk fib6_siblings under RCU?
Date: Mon, 25 May 2026 19:53:35 +0200	[thread overview]
Message-ID: <ahSMn9GB65ztRN2e@strlen.de> (raw)

Hello,

Sashiko claims we need this change:

diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c
--- a/net/ipv6/netfilter/nft_fib_ipv6.c
+++ b/net/ipv6/netfilter/nft_fib_ipv6.c
@@ -191,6 +191,9 @@ static bool nft_fib6_info_nh_uses_dev(struct fib6_info *rt,
 
                if (nft_fib6_info_nh_dev_match(nh_dev, dev))
                        return true;
+
+               if (!READ_ONCE(rt->fib6_nsiblings))
+                       return false;
        }
 
        return false;


Could ypu please check and send a followup if its correct?
AFAICS the nodes can be relinked to a *different* list and
then this turns into busyloop without the extra test.

https://sashiko.dev/#/patchset/20260520023411.391233-1-jiayuan.chen%40linux.dev

Thank you.

             reply	other threads:[~2026-05-25 17:53 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-25 17:53 Florian Westphal [this message]
2026-05-26  1:47 ` Followup needed for netfilter: nft_fib_ipv6: walk fib6_siblings under RCU? Jiayuan Chen

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