From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-180.mta0.migadu.com (out-180.mta0.migadu.com [91.218.175.180]) (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 65E3C24C06A for ; Wed, 6 May 2026 01:21:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778030477; cv=none; b=oPOEx3YbI/0Qm43cOrmc2uGhrdQ0rrF6nYg6vHp/d6OG0uVxKfKf9DjLxkx38gDxW61zvtgn/f435emaBPqC8lTPlwiHnlGfj3LeAqz4D8WvPNyMvnqOFFWEQCo4YtPqbZDPeXVZi+fGGffpsdjAcgFFafqo3WNUkdG0r8+KOAM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778030477; c=relaxed/simple; bh=Vhood+z/w+jZJdyiSb1/a4KFBlLJ6uXiaG/YOjTCMaA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=LA4Mr/3dVAYLryLXkCEZJeKUAPw0qjK5ea3RaAmhAETVaIJttuFH+Fb2L4iUamae1kfCvD+iQQOwXRyvvi0k33Uuz/CCLhR5s1DojzHFY9yW03i7yKB8vTRm57/zTwnFBB4/8htmc9D65an9pLUvMa8/Y8EJxjemGctPwTfHPOI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=WWj7c2Hx; arc=none smtp.client-ip=91.218.175.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="WWj7c2Hx" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778030471; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=tr3V8pLwz+iP9wrQYI1lMx+nE3te7x3TNUH+9XYN4a4=; b=WWj7c2HxssHYRy6nyawKL2HlAs+LN3N8KjAXDBipz7IV59cuQszFcd9aPydd8y8NDxccGi aDmzvDRF/kw2ZHSZrf+QJIHOAN98F5jeoE13dbbh8V0q1KYQkoMmcCAt3O1P2w35cphMhe MBhvyLkiegum9BOh89JTsIjRrRofMwY= From: Jiayuan Chen To: stable@vger.kernel.org Cc: Jiayuan Chen , Dong Chenchen , David Ahern , Eric Dumazet , Jakub Kicinski Subject: [PATCH 6.1.y] net: Fix icmp host relookup triggering ip_rt_bug Date: Wed, 6 May 2026 09:20:57 +0800 Message-ID: <20260506012057.285743-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Dong Chenchen [ Upstream commit c44daa7e3c73229f7ac74985acb8c7fb909c4e0a ] arp link failure may trigger ip_rt_bug while xfrm enabled, call trace is: WARNING: CPU: 0 PID: 0 at net/ipv4/route.c:1241 ip_rt_bug+0x14/0x20 Modules linked in: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:ip_rt_bug+0x14/0x20 Call Trace: ip_send_skb+0x14/0x40 __icmp_send+0x42d/0x6a0 ipv4_link_failure+0xe2/0x1d0 arp_error_report+0x3c/0x50 neigh_invalidate+0x8d/0x100 neigh_timer_handler+0x2e1/0x330 call_timer_fn+0x21/0x120 __run_timer_base.part.0+0x1c9/0x270 run_timer_softirq+0x4c/0x80 handle_softirqs+0xac/0x280 irq_exit_rcu+0x62/0x80 sysvec_apic_timer_interrupt+0x77/0x90 The script below reproduces this scenario: ip xfrm policy add src 0.0.0.0/0 dst 0.0.0.0/0 \ dir out priority 0 ptype main flag localok icmp ip l a veth1 type veth ip a a 192.168.141.111/24 dev veth0 ip l s veth0 up ping 192.168.141.155 -c 1 icmp_route_lookup() create input routes for locally generated packets while xfrm relookup ICMP traffic.Then it will set input route (dst->out = ip_rt_bug) to skb for DESTUNREACH. For ICMP err triggered by locally generated packets, dst->dev of output route is loopback. Generally, xfrm relookup verification is not required on loopback interfaces (net.ipv4.conf.lo.disable_xfrm = 1). Skip icmp relookup for locally generated packets to fix it. Fixes: 8b7817f3a959 ("[IPSEC]: Add ICMP host relookup support") Signed-off-by: Dong Chenchen Reviewed-by: David Ahern Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20241127040850.1513135-1-dongchenchen2@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Jiayuan Chen --- failed backport https://lore.kernel.org/stable/20250207161555-b1a8749027831a1a@stable.kernel.org/T/#m0c880c1f04f7211aea9b7f6b4de0b64aa1726417 --- net/ipv4/icmp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index d5d745c3e345..737e6caad716 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -509,6 +509,9 @@ static struct rtable *icmp_route_lookup(struct net *net, if (!IS_ERR(rt)) { if (rt != rt2) return rt; + if (inet_addr_type_dev_table(net, route_lookup_dev, + fl4->daddr) == RTN_LOCAL) + return rt; } else if (PTR_ERR(rt) == -EPERM) { rt = NULL; } else -- 2.43.0