Message ID | 2a78f16a-0ff5-46bf-983b-9ab038f5a5cd@163.com (mailing list archive) |
---|---|
State | Changes Requested |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | [net-next] seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors | expand |
On Thu, May 30, 2024 at 03:43:38PM +0800, Jianguo Wu wrote: > From: Jianguo Wu <wujianguo@chinatelecom.cn> > > input_action_end_dx4() and input_action_end_dx6() call NF_HOOK() for PREROUTING hook, > for PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), > otherwise may trigger a NULL pointer dereference, as below: nit: The text above should be line-wrapped so that it is no more than 75 columns wide. Link: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes > > [74830.647293] BUG: kernel NULL pointer dereference, address: 0000000000000090 > [74830.655633] #PF: supervisor read access in kernel mode > [74830.657888] #PF: error_code(0x0000) - not-present page > [74830.659500] PGD 0 P4D 0 > [74830.660450] Oops: 0000 [#1] PREEMPT SMP PTI > ... > [74830.664953] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 > [74830.666569] RIP: 0010:rpfilter_mt+0x44/0x15e [ipt_rpfilter] > ... > [74830.689725] Call Trace: > [74830.690402] <IRQ> > [74830.690953] ? show_trace_log_lvl+0x1c4/0x2df > [74830.692020] ? show_trace_log_lvl+0x1c4/0x2df > [74830.693095] ? ipt_do_table+0x286/0x710 [ip_tables] > [74830.694275] ? __die_body.cold+0x8/0xd > [74830.695205] ? page_fault_oops+0xac/0x140 > [74830.696244] ? exc_page_fault+0x62/0x150 > [74830.697225] ? asm_exc_page_fault+0x22/0x30 > [74830.698344] ? rpfilter_mt+0x44/0x15e [ipt_rpfilter] > [74830.699540] ipt_do_table+0x286/0x710 [ip_tables] > [74830.700758] ? ip6_route_input+0x19d/0x240 > [74830.701752] nf_hook_slow+0x3f/0xb0 > [74830.702678] input_action_end_dx4+0x19b/0x1e0 > [74830.703735] ? input_action_end_t+0xe0/0xe0 > [74830.704734] seg6_local_input_core+0x2d/0x60 > [74830.705782] lwtunnel_input+0x5b/0xb0 > [74830.706690] __netif_receive_skb_one_core+0x63/0xa0 > [74830.707825] process_backlog+0x99/0x140 > [74830.709538] __napi_poll+0x2c/0x160 > [74830.710673] net_rx_action+0x296/0x350 > [74830.711860] __do_softirq+0xcb/0x2ac > [74830.713049] do_softirq+0x63/0x90 > > input_action_end_dx4() passing a NULL indev to NF_HOOK(), and finally trigger a > NULL dereference in rpfilter_mt()->rpfilter_is_loopback(): > static bool > rpfilter_is_loopback(const struct sk_buff *skb, const struct net_device *in) > { > // in is NULL > return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; > } > > Fixes: 7a3f5b0de364 ("netfilter: add netfilter hooks to SRv6 data plane") nit: no blank line here. > > Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn> I am slightly puzzled that this bug was in the tree for so long without being noticed. But the above not withstanding, this looks good to me. Reviewed-by: Simon Horman <horms@kernel.org> ...
Hi, On Thu, May 30, 2024 at 03:43:38PM +0800, Jianguo Wu wrote: > From: Jianguo Wu <wujianguo@chinatelecom.cn> > > input_action_end_dx4() and input_action_end_dx6() call NF_HOOK() for PREROUTING hook, > for PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), > otherwise may trigger a NULL pointer dereference, as below: Could you also add a selftest to improve coverage of this infrastructure? Thanks.
Hi Simon, Thanks for your review, I will fix the commit log, and send v2 with your Reviewed-by tag. On 2024/6/4 2:21, Simon Horman wrote: > On Thu, May 30, 2024 at 03:43:38PM +0800, Jianguo Wu wrote: >> From: Jianguo Wu <wujianguo@chinatelecom.cn> >> >> input_action_end_dx4() and input_action_end_dx6() call NF_HOOK() for PREROUTING hook, >> for PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), >> otherwise may trigger a NULL pointer dereference, as below: > > nit: The text above should be line-wrapped so that it is > no more than 75 columns wide. > > Link: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes > >> >> [74830.647293] BUG: kernel NULL pointer dereference, address: 0000000000000090 >> [74830.655633] #PF: supervisor read access in kernel mode >> [74830.657888] #PF: error_code(0x0000) - not-present page >> [74830.659500] PGD 0 P4D 0 >> [74830.660450] Oops: 0000 [#1] PREEMPT SMP PTI >> ... >> [74830.664953] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 >> [74830.666569] RIP: 0010:rpfilter_mt+0x44/0x15e [ipt_rpfilter] >> ... >> [74830.689725] Call Trace: >> [74830.690402] <IRQ> >> [74830.690953] ? show_trace_log_lvl+0x1c4/0x2df >> [74830.692020] ? show_trace_log_lvl+0x1c4/0x2df >> [74830.693095] ? ipt_do_table+0x286/0x710 [ip_tables] >> [74830.694275] ? __die_body.cold+0x8/0xd >> [74830.695205] ? page_fault_oops+0xac/0x140 >> [74830.696244] ? exc_page_fault+0x62/0x150 >> [74830.697225] ? asm_exc_page_fault+0x22/0x30 >> [74830.698344] ? rpfilter_mt+0x44/0x15e [ipt_rpfilter] >> [74830.699540] ipt_do_table+0x286/0x710 [ip_tables] >> [74830.700758] ? ip6_route_input+0x19d/0x240 >> [74830.701752] nf_hook_slow+0x3f/0xb0 >> [74830.702678] input_action_end_dx4+0x19b/0x1e0 >> [74830.703735] ? input_action_end_t+0xe0/0xe0 >> [74830.704734] seg6_local_input_core+0x2d/0x60 >> [74830.705782] lwtunnel_input+0x5b/0xb0 >> [74830.706690] __netif_receive_skb_one_core+0x63/0xa0 >> [74830.707825] process_backlog+0x99/0x140 >> [74830.709538] __napi_poll+0x2c/0x160 >> [74830.710673] net_rx_action+0x296/0x350 >> [74830.711860] __do_softirq+0xcb/0x2ac >> [74830.713049] do_softirq+0x63/0x90 >> >> input_action_end_dx4() passing a NULL indev to NF_HOOK(), and finally trigger a >> NULL dereference in rpfilter_mt()->rpfilter_is_loopback(): >> static bool >> rpfilter_is_loopback(const struct sk_buff *skb, const struct net_device *in) >> { >> // in is NULL >> return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; >> } >> >> Fixes: 7a3f5b0de364 ("netfilter: add netfilter hooks to SRv6 data plane") > > nit: no blank line here. > >> >> Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn> > > I am slightly puzzled that this bug was in > the tree for so long without being noticed. > > But the above not withstanding, this looks good to me. > > Reviewed-by: Simon Horman <horms@kernel.org> > > ...
Hi, Pablo On 2024/6/4 3:23, Pablo Neira Ayuso wrote: > Hi, > > On Thu, May 30, 2024 at 03:43:38PM +0800, Jianguo Wu wrote: >> From: Jianguo Wu <wujianguo@chinatelecom.cn> >> >> input_action_end_dx4() and input_action_end_dx6() call NF_HOOK() for PREROUTING hook, >> for PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), >> otherwise may trigger a NULL pointer dereference, as below: > > Could you also add a selftest to improve coverage of this infrastructure? > Sure, I will add a selftest to cover this case. > Thanks.
On Tue, 2024-06-04 at 14:34 +0800, Jianguo Wu wrote: > Hi, Pablo > > On 2024/6/4 3:23, Pablo Neira Ayuso wrote: > > Hi, > > > > On Thu, May 30, 2024 at 03:43:38PM +0800, Jianguo Wu wrote: > > > From: Jianguo Wu <wujianguo@chinatelecom.cn> > > > > > > input_action_end_dx4() and input_action_end_dx6() call NF_HOOK() for PREROUTING hook, > > > for PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), > > > otherwise may trigger a NULL pointer dereference, as below: > > > > Could you also add a selftest to improve coverage of this infrastructure? > > > > Sure, I will add a selftest to cover this case. When re-submitting, please additionally target the 'net' tree, replacing the 'net-next' prefix with 'net', Thanks! Paolo
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 24e2b4b..c434940 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -941,8 +941,8 @@ static int input_action_end_dx6(struct sk_buff *skb, if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled)) return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, - dev_net(skb->dev), NULL, skb, NULL, - skb_dst(skb)->dev, input_action_end_dx6_finish); + dev_net(skb->dev), NULL, skb, skb->dev, + NULL, input_action_end_dx6_finish); return input_action_end_dx6_finish(dev_net(skb->dev), NULL, skb); drop: @@ -991,8 +991,8 @@ static int input_action_end_dx4(struct sk_buff *skb, if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled)) return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, - dev_net(skb->dev), NULL, skb, NULL, - skb_dst(skb)->dev, input_action_end_dx4_finish); + dev_net(skb->dev), NULL, skb, skb->dev, + NULL, input_action_end_dx4_finish); return input_action_end_dx4_finish(dev_net(skb->dev), NULL, skb); drop: