From 325ed8239309cb29f10ea58c5a668058ead11479 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 3 Oct 2005 13:57:23 -0700 Subject: [NET]: Fix packet timestamping. I've found the problem in general. It affects any 64-bit architecture. The problem occurs when you change the system time. Suppose that when you boot your system clock is forward by a day. This gets recorded down in skb_tv_base. You then wind the clock back by a day. From that point onwards the offset will be negative which essentially overflows the 32-bit variables they're stored in. In fact, why don't we just store the real time stamp in those 32-bit variables? After all, we're not going to overflow for quite a while yet. When we do overflow, we'll need a better solution of course. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/packet/af_packet.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 6a67a87384cc..499ae3df4a44 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -654,8 +654,8 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe __net_timestamp(skb); sock_enable_timestamp(sk); } - h->tp_sec = skb_tv_base.tv_sec + skb->tstamp.off_sec; - h->tp_usec = skb_tv_base.tv_usec + skb->tstamp.off_usec; + h->tp_sec = skb->tstamp.off_sec; + h->tp_usec = skb->tstamp.off_usec; sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h))); sll->sll_halen = 0; -- cgit v1.2.2