leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

xen-netback: make sure skb linear area covers checksum field

Browse Source 
skb_partial_csum_set requires that the linear area of the skb covers the
checksum field. The checksum setup code in netback was only doing that
pullup in the case when the pseudo header checksum was being recalculated
though. This patch makes that pullup unconditional. (I pullup the whole
transport header just for simplicity; the requirement is only for the check
field but in the case of UDP this is the last field in the header and in the
case of TCP it's the last but one).

The lack of pullup manifested as failures running Microsoft HCK network
tests on a pair of Windows 8 VMs and it has been verified that this patch
fixes the problem.

Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Paul Durrant 2013-12-11 16:37:40 +00:00 committed by David S. Miller
parent 3f823c15d5
commit d52eb0d46f
1 changed files with 28 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

60
drivers/net/xen-netback/netback.c
View File

@ -1199,42 +1199,40 @@ static int checksum_setup_ip(struct xenvif *vif, struct sk_buff *skb,
switch (ip_hdr(skb)->protocol) {
case IPPROTO_TCP:
err = maybe_pull_tail(skb,
off + sizeof(struct tcphdr),
MAX_IP_HDR_LEN);
if (err < 0)
goto out;
if (!skb_partial_csum_set(skb, off,
offsetof(struct tcphdr, check)))
goto out;
if (recalculate_partial_csum) {
err = maybe_pull_tail(skb,
off + sizeof(struct tcphdr),
MAX_IP_HDR_LEN);
if (err < 0)
goto out;
if (recalculate_partial_csum)
tcp_hdr(skb)->check =
~csum_tcpudp_magic(ip_hdr(skb)->saddr,
ip_hdr(skb)->daddr,
skb->len - off,
IPPROTO_TCP, 0);
}
break;
case IPPROTO_UDP:
err = maybe_pull_tail(skb,
off + sizeof(struct udphdr),
MAX_IP_HDR_LEN);
if (err < 0)
goto out;
if (!skb_partial_csum_set(skb, off,
offsetof(struct udphdr, check)))
goto out;
if (recalculate_partial_csum) {
err = maybe_pull_tail(skb,
off + sizeof(struct udphdr),
MAX_IP_HDR_LEN);
if (err < 0)
goto out;
if (recalculate_partial_csum)
udp_hdr(skb)->check =
~csum_tcpudp_magic(ip_hdr(skb)->saddr,
ip_hdr(skb)->daddr,
skb->len - off,
IPPROTO_UDP, 0);
}
break;
default:
goto out;
@ -1342,42 +1340,40 @@ static int checksum_setup_ipv6(struct xenvif *vif, struct sk_buff *skb,
switch (nexthdr) {
case IPPROTO_TCP:
err = maybe_pull_tail(skb,
off + sizeof(struct tcphdr),
MAX_IPV6_HDR_LEN);
if (err < 0)
goto out;
if (!skb_partial_csum_set(skb, off,
offsetof(struct tcphdr, check)))
goto out;
if (recalculate_partial_csum) {
err = maybe_pull_tail(skb,
off + sizeof(struct tcphdr),
MAX_IPV6_HDR_LEN);
if (err < 0)
goto out;
if (recalculate_partial_csum)
tcp_hdr(skb)->check =
~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
&ipv6_hdr(skb)->daddr,
skb->len - off,
IPPROTO_TCP, 0);
}
break;
case IPPROTO_UDP:
err = maybe_pull_tail(skb,
off + sizeof(struct udphdr),
MAX_IPV6_HDR_LEN);
if (err < 0)
goto out;
if (!skb_partial_csum_set(skb, off,
offsetof(struct udphdr, check)))
goto out;
if (recalculate_partial_csum) {
err = maybe_pull_tail(skb,
off + sizeof(struct udphdr),
MAX_IPV6_HDR_LEN);
if (err < 0)
goto out;
if (recalculate_partial_csum)
udp_hdr(skb)->check =
~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
&ipv6_hdr(skb)->daddr,
skb->len - off,
IPPROTO_UDP, 0);
}
break;
default:
goto out;