From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 693062EE262; Tue, 31 Mar 2026 16:36:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774974987; cv=none; b=LpNejpHNvd8SMNw56plYh/5jvHk6SC2i5J7itduop3ZiS6nAzbPTM235odQD0Ag/Qm11Oxxu70Lu6vMTfXjtEZO+l1hxfpGbabY5TpybYasbWm+xrv63K2C1R6U+EPnsLIWE7KvrqxM5cSTLqejEiuYBDwQUGAj009v4GW2VaaI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774974987; c=relaxed/simple; bh=cPjuQi3+JBJmxlg4ZLvPMlbICSlneDyfIsbUIVxGrsA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fKgttyTnz2R56sB2RKBdLqmT0Jc8qvwbjRZsH8LDYhVt8GKN2HGkEyu87dXk5PJUhcPY6ESjnELGk4d+NQ/QvsreYhUcwr26atfCTqlOxdW04arsphLQoiANwc1H1jlqiWYSx8A2nT4gL5LiFrdcp8nLIrXMa1CnIyD227zvsO8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RBPBFndj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="RBPBFndj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2D86C19424; Tue, 31 Mar 2026 16:36:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774974987; bh=cPjuQi3+JBJmxlg4ZLvPMlbICSlneDyfIsbUIVxGrsA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RBPBFndjiBUJ6Mjqk0gYVfgwfrGvtSs64xUCAfQ94vBg57iMMm8kO9ghKoBJyJVAR Rycndqn/5OrRZ/JNdY4SAPfZ+f9nWoOCQl0v2kh3PS5aHEARcOAyMW1Vycwkf0OQWL wbBI553/E0s7NslJzO6m/l7cm8SFeQn1d3ni3fwA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Kuniyuki Iwashima , David Ahern , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.19 119/342] ipv6: Dont remove permanent routes with exceptions from tb6_gc_hlist. Date: Tue, 31 Mar 2026 18:19:12 +0200 Message-ID: <20260331161803.389118910@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260331161758.909578033@linuxfoundation.org> References: <20260331161758.909578033@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kuniyuki Iwashima [ Upstream commit 4be7b99c253f0c85a255cc1db7127ba3232dfa30 ] The cited commit mechanically put fib6_remove_gc_list() just after every fib6_clean_expires() call. When a temporary route is promoted to a permanent route, there may already be exception routes tied to it. If fib6_remove_gc_list() removes the route from tb6_gc_hlist, such exception routes will no longer be aged. Let's replace fib6_remove_gc_list() with a new helper fib6_may_remove_gc_list() and use fib6_age_exceptions() there. Note that net->ipv6 is only compiled when CONFIG_IPV6 is enabled, so fib6_{add,remove,may_remove}_gc_list() are guarded. Fixes: 5eb902b8e719 ("net/ipv6: Remove expired routes with a separated list of routes.") Signed-off-by: Kuniyuki Iwashima Reviewed-by: David Ahern Link: https://patch.msgid.link/20260320072317.2561779-3-kuniyu@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/net/ip6_fib.h | 21 ++++++++++++++++++++- net/ipv6/addrconf.c | 4 ++-- net/ipv6/ip6_fib.c | 6 +++--- net/ipv6/route.c | 2 +- 4 files changed, 26 insertions(+), 7 deletions(-) diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index 88b0dd4d8e094..9f8b6814a96a0 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -507,12 +507,14 @@ void fib6_rt_update(struct net *net, struct fib6_info *rt, void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info, unsigned int flags); +void fib6_age_exceptions(struct fib6_info *rt, struct fib6_gc_args *gc_args, + unsigned long now); void fib6_run_gc(unsigned long expires, struct net *net, bool force); - void fib6_gc_cleanup(void); int fib6_init(void); +#if IS_ENABLED(CONFIG_IPV6) /* Add the route to the gc list if it is not already there * * The callers should hold f6i->fib6_table->tb6_lock. @@ -545,6 +547,23 @@ static inline void fib6_remove_gc_list(struct fib6_info *f6i) hlist_del_init(&f6i->gc_link); } +static inline void fib6_may_remove_gc_list(struct net *net, + struct fib6_info *f6i) +{ + struct fib6_gc_args gc_args; + + if (hlist_unhashed(&f6i->gc_link)) + return; + + gc_args.timeout = READ_ONCE(net->ipv6.sysctl.ip6_rt_gc_interval); + gc_args.more = 0; + + rcu_read_lock(); + fib6_age_exceptions(f6i, &gc_args, jiffies); + rcu_read_unlock(); +} +#endif + struct ipv6_route_iter { struct seq_net_private p; struct fib6_walker w; diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 27ab9d7adc649..3dcfa4b3094a8 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -2863,7 +2863,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao) fib6_add_gc_list(rt); } else { fib6_clean_expires(rt); - fib6_remove_gc_list(rt); + fib6_may_remove_gc_list(net, rt); } spin_unlock_bh(&table->tb6_lock); @@ -4836,7 +4836,7 @@ static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp, if (!(flags & RTF_EXPIRES)) { fib6_clean_expires(f6i); - fib6_remove_gc_list(f6i); + fib6_may_remove_gc_list(net, f6i); } else { fib6_set_expires(f6i, expires); fib6_add_gc_list(f6i); diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index a22af1c8f93ac..ffa7733598333 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -1133,7 +1133,7 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct fib6_info *rt, return -EEXIST; if (!(rt->fib6_flags & RTF_EXPIRES)) { fib6_clean_expires(iter); - fib6_remove_gc_list(iter); + fib6_may_remove_gc_list(info->nl_net, iter); } else { fib6_set_expires(iter, rt->expires); fib6_add_gc_list(iter); @@ -2348,8 +2348,8 @@ static void fib6_flush_trees(struct net *net) /* * Garbage collection */ -static void fib6_age_exceptions(struct fib6_info *rt, struct fib6_gc_args *gc_args, - unsigned long now) +void fib6_age_exceptions(struct fib6_info *rt, struct fib6_gc_args *gc_args, + unsigned long now) { bool may_expire = rt->fib6_flags & RTF_EXPIRES && rt->expires; int old_more = gc_args->more; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index e01331d965313..446f4de7d6a22 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1033,7 +1033,7 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, if (!addrconf_finite_timeout(lifetime)) { fib6_clean_expires(rt); - fib6_remove_gc_list(rt); + fib6_may_remove_gc_list(net, rt); } else { fib6_set_expires(rt, jiffies + HZ * lifetime); fib6_add_gc_list(rt); -- 2.51.0