* [PATCH] ipv4/ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally
@ 2012-12-21 1:12 Isaku Yamahata
2012-12-21 1:48 ` Eric Dumazet
0 siblings, 1 reply; 3+ messages in thread
From: Isaku Yamahata @ 2012-12-21 1:12 UTC (permalink / raw)
To: netdev; +Cc: yamahata
ipgre_tunnel_xmit() parses network header as IP unconditionally.
But transmitting packets are not always IP packet. For example such packet
can be sent by packet socket with sockaddr_ll.sll_protocol set.
So make the function check if skb->protocol is IP.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
---
net/ipv4/ip_gre.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index a85ae2f..8fcf0ed 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -760,7 +760,10 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
gre_hlen = 0;
- tiph = (const struct iphdr *)skb->data;
+ if (skb->protocol == htons(ETH_P_IP))
+ tiph = (const struct iphdr *)skb->data;
+ else
+ tiph = &tunnel->parms.iph;
} else {
gre_hlen = tunnel->hlen;
tiph = &tunnel->parms.iph;
--
1.7.10.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] ipv4/ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally
2012-12-21 1:12 [PATCH] ipv4/ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally Isaku Yamahata
@ 2012-12-21 1:48 ` Eric Dumazet
2012-12-21 21:15 ` David Miller
0 siblings, 1 reply; 3+ messages in thread
From: Eric Dumazet @ 2012-12-21 1:48 UTC (permalink / raw)
To: Isaku Yamahata; +Cc: netdev
On Fri, 2012-12-21 at 10:12 +0900, Isaku Yamahata wrote:
> ipgre_tunnel_xmit() parses network header as IP unconditionally.
> But transmitting packets are not always IP packet. For example such packet
> can be sent by packet socket with sockaddr_ll.sll_protocol set.
> So make the function check if skb->protocol is IP.
>
> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
> ---
> net/ipv4/ip_gre.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
> index a85ae2f..8fcf0ed 100644
> --- a/net/ipv4/ip_gre.c
> +++ b/net/ipv4/ip_gre.c
> @@ -760,7 +760,10 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
>
> if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
> gre_hlen = 0;
> - tiph = (const struct iphdr *)skb->data;
> + if (skb->protocol == htons(ETH_P_IP))
> + tiph = (const struct iphdr *)skb->data;
> + else
> + tiph = &tunnel->parms.iph;
> } else {
> gre_hlen = tunnel->hlen;
> tiph = &tunnel->parms.iph;
Seems good to me thanks !
Acked-by: Eric Dumazet <edumazet@google.com>
BTW, it seems another bug exists at line 931 : We dereference tiph while
it could point to freed memory because of the skb_realloc_headroom() at
line 893
I'll send a patch.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] ipv4/ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally
2012-12-21 1:48 ` Eric Dumazet
@ 2012-12-21 21:15 ` David Miller
0 siblings, 0 replies; 3+ messages in thread
From: David Miller @ 2012-12-21 21:15 UTC (permalink / raw)
To: eric.dumazet; +Cc: yamahata, netdev
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 20 Dec 2012 17:48:41 -0800
> On Fri, 2012-12-21 at 10:12 +0900, Isaku Yamahata wrote:
>> ipgre_tunnel_xmit() parses network header as IP unconditionally.
>> But transmitting packets are not always IP packet. For example such packet
>> can be sent by packet socket with sockaddr_ll.sll_protocol set.
>> So make the function check if skb->protocol is IP.
>>
>> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
>> ---
>> net/ipv4/ip_gre.c | 5 ++++-
>> 1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
>> index a85ae2f..8fcf0ed 100644
>> --- a/net/ipv4/ip_gre.c
>> +++ b/net/ipv4/ip_gre.c
>> @@ -760,7 +760,10 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
>>
>> if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
>> gre_hlen = 0;
>> - tiph = (const struct iphdr *)skb->data;
>> + if (skb->protocol == htons(ETH_P_IP))
>> + tiph = (const struct iphdr *)skb->data;
>> + else
>> + tiph = &tunnel->parms.iph;
>> } else {
>> gre_hlen = tunnel->hlen;
>> tiph = &tunnel->parms.iph;
>
> Seems good to me thanks !
>
> Acked-by: Eric Dumazet <edumazet@google.com>
Applied.
^ permalink raw reply [flat|nested] 3+ messages in thread
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2012-12-21 1:12 [PATCH] ipv4/ip_gre: make ipgre_tunnel_xmit() not parse network header as IP unconditionally Isaku Yamahata
2012-12-21 1:48 ` Eric Dumazet
2012-12-21 21:15 ` David Miller
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