netdev - net: alignment problem in icmp code

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Message-ID: <20071020233540.43d2f103@poseidon.drzeus.cx>
Date:	Sat, 20 Oct 2007 23:35:40 +0200
From:	Pierre Ossman <drzeus@...eus.cx>
To:	davem@...emloft.net, netdev@...r.kernel.org
Subject: net: alignment problem in icmp code

Structure assignment have to be aligned just like any assignment, and the skb could point to anything. So take the safe route and use a memcpy().

Signed-off-by: Pierre Ossman <drzeus@...eus.cx>
---

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 272c69e..a7e2ec9 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -783,7 +783,7 @@ static void icmp_echo(struct sk_buff *skb)
 	if (!sysctl_icmp_echo_ignore_all) {
 		struct icmp_bxm icmp_param;
 
-		icmp_param.data.icmph	   = *icmp_hdr(skb);
+		memcpy(&icmp_param.data.icmph, icmp_hdr(skb), sizeof(struct icmphdr));
 		icmp_param.data.icmph.type = ICMP_ECHOREPLY;
 		icmp_param.skb		   = skb;
 		icmp_param.offset	   = 0;
@@ -819,7 +819,7 @@ static void icmp_timestamp(struct sk_buff *skb)
 	icmp_param.data.times[2] = icmp_param.data.times[1];
 	if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4))
 		BUG();
-	icmp_param.data.icmph	   = *icmp_hdr(skb);
+	memcpy(&icmp_param.data.icmph, icmp_hdr(skb), sizeof(struct icmphdr));
 	icmp_param.data.icmph.type = ICMP_TIMESTAMPREPLY;
 	icmp_param.data.icmph.code = 0;
 	icmp_param.skb		   = skb;

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