| Message ID | 20241126025943.1223254-1-dongchenchen2@huawei.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v2] net: Fix icmp host relookup triggering ip_rt_bug | expand |
On 11/25/24 7:59 PM, Dong Chenchen wrote: > diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c > index 4f088fa1c2f2..0d51f8434187 100644 > --- a/net/ipv4/icmp.c > +++ b/net/ipv4/icmp.c > @@ -515,7 +515,10 @@ static struct rtable *icmp_route_lookup(struct net *net, struct flowi4 *fl4, > flowi4_to_flowi(fl4), NULL, 0); > rt = dst_rtable(dst); > if (!IS_ERR(dst)) { > - if (rt != rt2) > + unsigned int addr_type = inet_addr_type_dev_table(net, > + route_lookup_dev, fl4->daddr); > + unsigned int addr_type; addr_type = inet_addr_type_dev_table(net, route_lookup_dev, fl4->daddr); allows the lines to meet column limits and alignment requirements. > + if (rt != rt2 || addr_type == RTN_LOCAL) > return rt; > } else if (PTR_ERR(dst) == -EPERM) { > rt = NULL;
\\ On Tue, Nov 26, 2024 at 5:23 PM David Ahern <dsahern@kernel.org> wrote: > > On 11/25/24 7:59 PM, Dong Chenchen wrote: > > diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c > > index 4f088fa1c2f2..0d51f8434187 100644 > > --- a/net/ipv4/icmp.c > > +++ b/net/ipv4/icmp.c > > @@ -515,7 +515,10 @@ static struct rtable *icmp_route_lookup(struct net *net, struct flowi4 *fl4, > > flowi4_to_flowi(fl4), NULL, 0); > > rt = dst_rtable(dst); > > if (!IS_ERR(dst)) { > > - if (rt != rt2) > > + unsigned int addr_type = inet_addr_type_dev_table(net, > > + route_lookup_dev, fl4->daddr); > > + > > unsigned int addr_type; > > addr_type = inet_addr_type_dev_table(net, route_lookup_dev, > fl4->daddr); > > allows the lines to meet column limits and alignment requirements. > > > + if (rt != rt2 || c == RTN_LOCAL) > > return rt; > > } else if (PTR_ERR(dst) == -EPERM) { > > rt = NULL; > Also, we can avoid the expensive call to inet_addr_type_dev_table() and addr_type variable with : if (rt != rt2) return rt; if (inet_addr_type_dev_table(net, route_lookup_dev, fl4->daddr) == RTN_LOCAL) return rt;
On 2024/11/27 1:26, Eric Dumazet wrote: > \\ > > On Tue, Nov 26, 2024 at 5:23 PM David Ahern <dsahern@kernel.org> wrote: >> On 11/25/24 7:59 PM, Dong Chenchen wrote: >>> diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c >>> index 4f088fa1c2f2..0d51f8434187 100644 >>> --- a/net/ipv4/icmp.c >>> +++ b/net/ipv4/icmp.c >>> @@ -515,7 +515,10 @@ static struct rtable *icmp_route_lookup(struct net *net, struct flowi4 *fl4, >>> flowi4_to_flowi(fl4), NULL, 0); >>> rt = dst_rtable(dst); >>> if (!IS_ERR(dst)) { >>> - if (rt != rt2) >>> + unsigned int addr_type = inet_addr_type_dev_table(net, >>> + route_lookup_dev, fl4->daddr); >>> + >> unsigned int addr_type; >> >> addr_type = inet_addr_type_dev_table(net, route_lookup_dev, >> fl4->daddr); >> >> allows the lines to meet column limits and alignment requirements. >> >>> + if (rt != rt2 || c == RTN_LOCAL) >>> return rt; >>> } else if (PTR_ERR(dst) == -EPERM) { >>> rt = NULL; > Also, we can avoid the expensive call to inet_addr_type_dev_table() > and addr_type variable with : > > if (rt != rt2) > return rt; > if (inet_addr_type_dev_table(net, route_lookup_dev, > fl4->daddr) == RTN_LOCAL) > return rt; Thanks for your suggestions! v3 will be sent.
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 4f088fa1c2f2..0d51f8434187 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -515,7 +515,10 @@ static struct rtable *icmp_route_lookup(struct net *net, struct flowi4 *fl4, flowi4_to_flowi(fl4), NULL, 0); rt = dst_rtable(dst); if (!IS_ERR(dst)) { - if (rt != rt2) + unsigned int addr_type = inet_addr_type_dev_table(net, + route_lookup_dev, fl4->daddr); + + if (rt != rt2 || addr_type == RTN_LOCAL) return rt; } else if (PTR_ERR(dst) == -EPERM) { rt = NULL;
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> --- v2: Skip icmp relookup to fix bug --- net/ipv4/icmp.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)