icmp: avoid allocating large struct on stack
struct icmp_bxm is a large struct, reduce stack usage
by allocating it on heap.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 2864ca3..5f7d11a 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -482,7 +482,7 @@
{
struct iphdr *iph;
int room;
- struct icmp_bxm icmp_param;
+ struct icmp_bxm *icmp_param;
struct rtable *rt = skb_rtable(skb_in);
struct ipcm_cookie ipc;
struct flowi4 fl4;
@@ -558,9 +558,13 @@
}
}
+ icmp_param = kmalloc(sizeof(*icmp_param), GFP_ATOMIC);
+ if (!icmp_param)
+ return;
+
sk = icmp_xmit_lock(net);
if (sk == NULL)
- return;
+ goto out_free;
/*
* Construct source address and options.
@@ -586,7 +590,7 @@
IPTOS_PREC_INTERNETCONTROL) :
iph->tos;
- if (ip_options_echo(&icmp_param.replyopts.opt.opt, skb_in))
+ if (ip_options_echo(&icmp_param->replyopts.opt.opt, skb_in))
goto out_unlock;
@@ -594,19 +598,19 @@
* Prepare data for ICMP header.
*/
- icmp_param.data.icmph.type = type;
- icmp_param.data.icmph.code = code;
- icmp_param.data.icmph.un.gateway = info;
- icmp_param.data.icmph.checksum = 0;
- icmp_param.skb = skb_in;
- icmp_param.offset = skb_network_offset(skb_in);
+ icmp_param->data.icmph.type = type;
+ icmp_param->data.icmph.code = code;
+ icmp_param->data.icmph.un.gateway = info;
+ icmp_param->data.icmph.checksum = 0;
+ icmp_param->skb = skb_in;
+ icmp_param->offset = skb_network_offset(skb_in);
inet_sk(sk)->tos = tos;
ipc.addr = iph->saddr;
- ipc.opt = &icmp_param.replyopts.opt;
+ ipc.opt = &icmp_param->replyopts.opt;
ipc.tx_flags = 0;
rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos,
- type, code, &icmp_param);
+ type, code, icmp_param);
if (IS_ERR(rt))
goto out_unlock;
@@ -618,19 +622,21 @@
room = dst_mtu(&rt->dst);
if (room > 576)
room = 576;
- room -= sizeof(struct iphdr) + icmp_param.replyopts.opt.opt.optlen;
+ room -= sizeof(struct iphdr) + icmp_param->replyopts.opt.opt.optlen;
room -= sizeof(struct icmphdr);
- icmp_param.data_len = skb_in->len - icmp_param.offset;
- if (icmp_param.data_len > room)
- icmp_param.data_len = room;
- icmp_param.head_len = sizeof(struct icmphdr);
+ icmp_param->data_len = skb_in->len - icmp_param->offset;
+ if (icmp_param->data_len > room)
+ icmp_param->data_len = room;
+ icmp_param->head_len = sizeof(struct icmphdr);
- icmp_push_reply(&icmp_param, &fl4, &ipc, &rt);
+ icmp_push_reply(icmp_param, &fl4, &ipc, &rt);
ende:
ip_rt_put(rt);
out_unlock:
icmp_xmit_unlock(sk);
+out_free:
+ kfree(icmp_param);
out:;
}
EXPORT_SYMBOL(icmp_send);