net: bridge: use mld2r_ngrec instead of icmpv6_dataun

br_ip6_multicast_mld2_report function uses icmp6h
to parse mld2_report packet.

mld2r_ngrec defines mld2r_hdr.icmp6_dataun.un_data16[1]
in include/net/mld.h.

So, it is more compact to use mld2r rather than icmp6h.

By doing printk test, it is confirmed that
icmp6h->icmp6_dataun.un_data16[1] and mld2r->mld2r_ngrec are
indeed equivalent.

Also, sizeof(*mld2r) and sizeof(*icmp6h) are equivalent, too.

Signed-off-by: MichelleJin <shjy180909@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
MichelleJin 2021-08-29 04:32:29 +00:00 committed by David S. Miller
parent 429205da6c
commit 6baeb3951c

View File

@ -2731,8 +2731,8 @@ static int br_ip6_multicast_mld2_report(struct net_bridge_mcast *brmctx,
struct net_bridge_mdb_entry *mdst;
struct net_bridge_port_group *pg;
unsigned int nsrcs_offset;
struct mld2_report *mld2r;
const unsigned char *src;
struct icmp6hdr *icmp6h;
struct in6_addr *h_addr;
struct mld2_grec *grec;
unsigned int grec_len;
@ -2740,12 +2740,12 @@ static int br_ip6_multicast_mld2_report(struct net_bridge_mcast *brmctx,
int i, len, num;
int err = 0;
if (!ipv6_mc_may_pull(skb, sizeof(*icmp6h)))
if (!ipv6_mc_may_pull(skb, sizeof(*mld2r)))
return -EINVAL;
icmp6h = icmp6_hdr(skb);
num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
len = skb_transport_offset(skb) + sizeof(*icmp6h);
mld2r = (struct mld2_report *)icmp6_hdr(skb);
num = ntohs(mld2r->mld2r_ngrec);
len = skb_transport_offset(skb) + sizeof(*mld2r);
for (i = 0; i < num; i++) {
__be16 *_nsrcs, __nsrcs;