From 9ecd04bc04af7df98b3a93c571e31b6ef6a90681 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 8 Nov 2011 10:45:04 +0000 Subject: sch_choke: use skb_header_pointer() Remove the assumption that skb_get_rxhash() makes IP header and ports linear, and use skb_header_pointer() instead in choke_match_flow() This permits __skb_get_rxhash() to use skb_header_pointer() eventually. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/sched/sch_choke.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) (limited to 'net') diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c index 3422b25df9e4..061bcb744bbd 100644 --- a/net/sched/sch_choke.c +++ b/net/sched/sch_choke.c @@ -152,15 +152,14 @@ static bool choke_match_flow(struct sk_buff *skb1, { int off1, off2, poff; const u32 *ports1, *ports2; + u32 _ports1, _ports2; u8 ip_proto; __u32 hash1; if (skb1->protocol != skb2->protocol) return false; - /* Use hash value as quick check - * Assumes that __skb_get_rxhash makes IP header and ports linear - */ + /* Use rxhash value as quick check */ hash1 = skb_get_rxhash(skb1); if (!hash1 || hash1 != skb_get_rxhash(skb2)) return false; @@ -172,10 +171,12 @@ static bool choke_match_flow(struct sk_buff *skb1, switch (skb1->protocol) { case __constant_htons(ETH_P_IP): { const struct iphdr *ip1, *ip2; + struct iphdr _ip1, _ip2; - ip1 = (const struct iphdr *) (skb1->data + off1); - ip2 = (const struct iphdr *) (skb2->data + off2); - + ip1 = skb_header_pointer(skb1, off1, sizeof(_ip1), &_ip1); + ip2 = skb_header_pointer(skb2, off2, sizeof(_ip2), &_ip2); + if (!ip1 || !ip2) + return false; ip_proto = ip1->protocol; if (ip_proto != ip2->protocol || ip1->saddr != ip2->saddr || ip1->daddr != ip2->daddr) @@ -190,9 +191,12 @@ static bool choke_match_flow(struct sk_buff *skb1, case __constant_htons(ETH_P_IPV6): { const struct ipv6hdr *ip1, *ip2; + struct ipv6hdr _ip1, _ip2; - ip1 = (const struct ipv6hdr *) (skb1->data + off1); - ip2 = (const struct ipv6hdr *) (skb2->data + off2); + ip1 = skb_header_pointer(skb1, off1, sizeof(_ip1), &_ip1); + ip2 = skb_header_pointer(skb2, off2, sizeof(_ip2), &_ip2); + if (!ip1 || !ip2) + return false; ip_proto = ip1->nexthdr; if (ip_proto != ip2->nexthdr || @@ -214,8 +218,11 @@ static bool choke_match_flow(struct sk_buff *skb1, off1 += poff; off2 += poff; - ports1 = (__force u32 *)(skb1->data + off1); - ports2 = (__force u32 *)(skb2->data + off2); + ports1 = skb_header_pointer(skb1, off1, sizeof(_ports1), &_ports1); + ports2 = skb_header_pointer(skb2, off2, sizeof(_ports2), &_ports2); + if (!ports1 || !ports2) + return false; + return *ports1 == *ports2; } -- cgit v1.2.3-59-g8ed1b