6.12-stable review patch. If anyone has any objections, please let me know.
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From: Dong Chenchen dongchenchen2@huawei.com
[ 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: <IRQ> 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 dongchenchen2@huawei.com Reviewed-by: David Ahern dsahern@kernel.org Reviewed-by: Eric Dumazet edumazet@google.com Link: https://patch.msgid.link/20241127040850.1513135-1-dongchenchen2@huawei.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/icmp.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index e1384e7331d82..c3ad41573b33e 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -519,6 +519,9 @@ static struct rtable *icmp_route_lookup(struct net *net, if (!IS_ERR(dst)) { 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(dst) == -EPERM) { rt = NULL; } else {