From 8fb479a47c869820966e7298f38038aa334d889c Mon Sep 17 00:00:00 2001 From: Antonio Quartulli Date: Wed, 23 Oct 2013 23:36:30 +0200 Subject: netpoll: fix rx_hook() interface by passing the skb Right now skb->data is passed to rx_hook() even if the skb has not been linearised and without giving rx_hook() a way to linearise it. Change the rx_hook() interface and make it accept the skb and the offset to the UDP payload as arguments. rx_hook() is also renamed to rx_skb_hook() to ensure that out of the tree users notice the API change. In this way any rx_skb_hook() implementation can perform all the needed operations to properly (and safely) access the skb data. Signed-off-by: Antonio Quartulli Signed-off-by: David S. Miller --- net/core/netpoll.c | 31 ++++++++++++++++++------------- 1 file changed, 18 insertions(+), 13 deletions(-) (limited to 'net/core') diff --git a/net/core/netpoll.c b/net/core/netpoll.c index fc75c9e461b8..8f971990677c 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -636,8 +636,9 @@ static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo netpoll_send_skb(np, send_skb); - /* If there are several rx_hooks for the same address, - we're fine by sending a single reply */ + /* If there are several rx_skb_hooks for the same + * address we're fine by sending a single reply + */ break; } spin_unlock_irqrestore(&npinfo->rx_lock, flags); @@ -719,8 +720,9 @@ static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo netpoll_send_skb(np, send_skb); - /* If there are several rx_hooks for the same address, - we're fine by sending a single reply */ + /* If there are several rx_skb_hooks for the same + * address, we're fine by sending a single reply + */ break; } spin_unlock_irqrestore(&npinfo->rx_lock, flags); @@ -756,11 +758,12 @@ static bool pkt_is_ns(struct sk_buff *skb) int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) { - int proto, len, ulen; - int hits = 0; + int proto, len, ulen, data_len; + int hits = 0, offset; const struct iphdr *iph; struct udphdr *uh; struct netpoll *np, *tmp; + uint16_t source; if (list_empty(&npinfo->rx_np)) goto out; @@ -820,7 +823,10 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) len -= iph->ihl*4; uh = (struct udphdr *)(((char *)iph) + iph->ihl*4); + offset = (unsigned char *)(uh + 1) - skb->data; ulen = ntohs(uh->len); + data_len = skb->len - offset; + source = ntohs(uh->source); if (ulen != len) goto out; @@ -834,9 +840,7 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) if (np->local_port && np->local_port != ntohs(uh->dest)) continue; - np->rx_hook(np, ntohs(uh->source), - (char *)(uh+1), - ulen - sizeof(struct udphdr)); + np->rx_skb_hook(np, source, skb, offset, data_len); hits++; } } else { @@ -859,7 +863,10 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) if (!pskb_may_pull(skb, sizeof(struct udphdr))) goto out; uh = udp_hdr(skb); + offset = (unsigned char *)(uh + 1) - skb->data; ulen = ntohs(uh->len); + data_len = skb->len - offset; + source = ntohs(uh->source); if (ulen != skb->len) goto out; if (udp6_csum_init(skb, uh, IPPROTO_UDP)) @@ -872,9 +879,7 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) if (np->local_port && np->local_port != ntohs(uh->dest)) continue; - np->rx_hook(np, ntohs(uh->source), - (char *)(uh+1), - ulen - sizeof(struct udphdr)); + np->rx_skb_hook(np, source, skb, offset, data_len); hits++; } #endif @@ -1062,7 +1067,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) npinfo->netpoll = np; - if (np->rx_hook) { + if (np->rx_skb_hook) { spin_lock_irqsave(&npinfo->rx_lock, flags); npinfo->rx_flags |= NETPOLL_RX_ENABLED; list_add_tail(&np->rx, &npinfo->rx_np); -- cgit v1.2.3 From 6f092343855a71e03b8d209815d8c45bf3a27fcd Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Fri, 1 Nov 2013 15:01:10 +0800 Subject: net: flow_dissector: fail on evil iph->ihl We don't validate iph->ihl which may lead a dead loop if we meet a IPIP skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl is evil (less than 5). This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae (rps: support IPIP encapsulation). Cc: Eric Dumazet Cc: Petr Matousek Cc: Michael S. Tsirkin Cc: Daniel Borkmann Signed-off-by: Jason Wang Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core') diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 8d7d0dd72db2..143b6fdb9647 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -40,7 +40,7 @@ again: struct iphdr _iph; ip: iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); - if (!iph) + if (!iph || iph->ihl < 5) return false; if (ip_is_fragment(iph)) -- cgit v1.2.3