bridge: fix igmpv3 / mldv2 report parsing
With the newly introduced helper functions the skb pulling is hidden in
the checksumming function - and undone before returning to the caller.
The IGMPv3 and MLDv2 report parsing functions in the bridge still
assumed that the skb is pointing to the beginning of the IGMP/MLD
message while it is now kept at the beginning of the IPv4/6 header,
breaking the message parsing and creating packet loss.
Fixing this by taking the offset between IP and IGMP/MLD header into
account, too.
Fixes: 9afd85c9e455 ("net: Export IGMP/MLD message validation code")
Reported-by: Tobias Powalowski <tobias.powalowski@googlemail.com>
Tested-by: Tobias Powalowski <tobias.powalowski@googlemail.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 66efdc2..480b3de 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1006,7 +1006,7 @@
ih = igmpv3_report_hdr(skb);
num = ntohs(ih->ngrec);
- len = sizeof(*ih);
+ len = skb_transport_offset(skb) + sizeof(*ih);
for (i = 0; i < num; i++) {
len += sizeof(*grec);
@@ -1067,7 +1067,7 @@
icmp6h = icmp6_hdr(skb);
num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
- len = sizeof(*icmp6h);
+ len = skb_transport_offset(skb) + sizeof(*icmp6h);
for (i = 0; i < num; i++) {
__be16 *nsrcs, _nsrcs;
