2020-03-17 02:06:19

by Haishuang Yan

Subject: [PATCH v2 1/2] netfilter: nf_flow_table: reload ip{v6}h in nf_flow_nat_ip{v6}

Since nf_flow_snat_port and nf_flow_snat_ip{v6} call pskb_may_pull()
which may change skb->data, so we need to reload ip{v6}h at the right
palce.

Fixes: a908fdec3dda ("netfilter: nf_flow_table: move ipv6 offload hook
code to nf_flow_table")
Fixes: 7d2086871762 ("netfilter: nf_flow_table: move ipv4 offload hook
code to nf_flow_table")
Signed-off-by: Haishuang Yan <[email protected]>
---
v2: collapse the patches
---
net/netfilter/nf_flow_table_ip.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 5272721..942bda5 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -146,11 +146,12 @@ static int nf_flow_nat_ip(const struct flow_offload *flow, struct sk_buff *skb,

if (test_bit(NF_FLOW_SNAT, &flow->flags) &&
(nf_flow_snat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
- nf_flow_snat_ip(flow, skb, iph, thoff, dir) < 0))
+ nf_flow_snat_ip(flow, skb, ip_hdr(skb), thoff, dir) < 0))
return -1;
+ iph = ip_hdr(skb);
if (test_bit(NF_FLOW_DNAT, &flow->flags) &&
(nf_flow_dnat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
- nf_flow_dnat_ip(flow, skb, iph, thoff, dir) < 0))
+ nf_flow_dnat_ip(flow, skb, ip_hdr(skb), thoff, dir) < 0))
return -1;

return 0;
@@ -417,11 +418,12 @@ static int nf_flow_nat_ipv6(const struct flow_offload *flow,

if (test_bit(NF_FLOW_SNAT, &flow->flags) &&
(nf_flow_snat_port(flow, skb, thoff, ip6h->nexthdr, dir) < 0 ||
- nf_flow_snat_ipv6(flow, skb, ip6h, thoff, dir) < 0))
+ nf_flow_snat_ipv6(flow, skb, ipv6_hdr(skb), thoff, dir) < 0))
return -1;
+ ip6h = ipv6_hdr(skb);
if (test_bit(NF_FLOW_DNAT, &flow->flags) &&
(nf_flow_dnat_port(flow, skb, thoff, ip6h->nexthdr, dir) < 0 ||
- nf_flow_dnat_ipv6(flow, skb, ip6h, thoff, dir) < 0))
+ nf_flow_dnat_ipv6(flow, skb, ipv6_hdr(skb), thoff, dir) < 0))
return -1;

return 0;
--
1.8.3.1

2020-03-17 02:06:30

by Haishuang Yan

Subject: [PATCH v2 2/2] netfilter: nf_flow_table: reload ip{v6}h in nf_flow_tuple_ip{v6}

Since pskb_may_pull may change skb->data, so we need to reload ip{v6}h at
the right place.

Fixes: a908fdec3dda ("netfilter: nf_flow_table: move ipv6 offload hook
code to nf_flow_table")
Fixes: 7d2086871762 ("netfilter: nf_flow_table: move ipv4 offload hook
code to nf_flow_table")
Signed-off-by: Haishuang Yan <[email protected]>
---
v2: collapse the patches
---
net/netfilter/nf_flow_table_ip.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 942bda5..610c60a 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -190,6 +190,7 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
if (!pskb_may_pull(skb, thoff + sizeof(*ports)))
return -1;

+ iph = ip_hdr(skb);
ports = (struct flow_ports *)(skb_network_header(skb) + thoff);

tuple->src_v4.s_addr = iph->saddr;
@@ -452,6 +453,7 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
if (!pskb_may_pull(skb, thoff + sizeof(*ports)))
return -1;

+ ip6h = ipv6_hdr(skb);
ports = (struct flow_ports *)(skb_network_header(skb) + thoff);

tuple->src_v6 = ip6h->saddr;
--
1.8.3.1

2020-03-19 20:06:16

by Pablo Neira Ayuso

Subject: Re: [PATCH v2 1/2] netfilter: nf_flow_table: reload ip{v6}h in nf_flow_nat_ip{v6}

On Tue, Mar 17, 2020 at 10:02:52AM +0800, Haishuang Yan wrote:
> Since nf_flow_snat_port and nf_flow_snat_ip{v6} call pskb_may_pull()
> which may change skb->data, so we need to reload ip{v6}h at the right
> palce.

Applied, thanks.

2020-03-19 20:06:50

by Pablo Neira Ayuso

Subject: Re: [PATCH v2 2/2] netfilter: nf_flow_table: reload ip{v6}h in nf_flow_tuple_ip{v6}

On Tue, Mar 17, 2020 at 10:02:53AM +0800, Haishuang Yan wrote:
> Since pskb_may_pull may change skb->data, so we need to reload ip{v6}h at
> the right place.

Also applied, thanks.