From 29a3cad5c6ae9e7fbf1509d01d39c3c3c38f11f9 Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Tue, 28 May 2013 20:34:26 +0000 Subject: [PATCH] ipv6: Correct comparisons and calculations using skb->tail and skb-transport_header This corrects an regression introduced by "net: Use 16bits for *_headers fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In that case skb->tail will be a pointer whereas skb->transport_header will be an offset from head. This is corrected by using wrappers that ensure that comparisons and calculations are always made using pointers. Signed-off-by: Simon Horman Signed-off-by: David S. Miller --- net/ipv6/exthdrs_core.c | 2 +- net/ipv6/icmp.c | 2 +- net/ipv6/mcast.c | 5 +++-- net/ipv6/mip6.c | 6 ++++-- net/ipv6/ndisc.c | 9 +++++---- net/ipv6/output_core.c | 3 ++- net/ipv6/raw.c | 3 ++- net/ipv6/route.c | 2 +- 8 files changed, 19 insertions(+), 13 deletions(-) diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c index c5e83fae4df4..140748debc4a 100644 --- a/net/ipv6/exthdrs_core.c +++ b/net/ipv6/exthdrs_core.c @@ -115,7 +115,7 @@ EXPORT_SYMBOL(ipv6_skip_exthdr); int ipv6_find_tlv(struct sk_buff *skb, int offset, int type) { const unsigned char *nh = skb_network_header(skb); - int packet_len = skb->tail - skb->network_header; + int packet_len = skb_tail_pointer(skb) - skb_network_header(skb); struct ipv6_opt_hdr *hdr; int len; diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 1d2902e61786..4b4890bbe16d 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -399,7 +399,7 @@ static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info) int err = 0; if ((u8 *)hdr < skb->head || - (skb->network_header + sizeof(*hdr)) > skb->tail) + (skb_network_header(skb) + sizeof(*hdr)) > skb_tail_pointer(skb)) return; /* diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index bfa6cc36ef2a..72c8bfe06bb4 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -1409,8 +1409,9 @@ static void mld_sendpack(struct sk_buff *skb) idev = __in6_dev_get(skb->dev); IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); - payload_len = (skb->tail - skb->network_header) - sizeof(*pip6); - mldlen = skb->tail - skb->transport_header; + payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) - + sizeof(*pip6); + mldlen = skb_tail_pointer(skb) - skb_transport_header(skb); pip6->payload_len = htons(payload_len); pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen, diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c index 0f9bdc5ee9f3..9ac01dc9402e 100644 --- a/net/ipv6/mip6.c +++ b/net/ipv6/mip6.c @@ -268,7 +268,8 @@ static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb, struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); const unsigned char *nh = skb_network_header(skb); - unsigned int packet_len = skb->tail - skb->network_header; + unsigned int packet_len = skb_tail_pointer(skb) - + skb_network_header(skb); int found_rhdr = 0; *nexthdr = &ipv6_hdr(skb)->nexthdr; @@ -404,7 +405,8 @@ static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb, struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); const unsigned char *nh = skb_network_header(skb); - unsigned int packet_len = skb->tail - skb->network_header; + unsigned int packet_len = skb_tail_pointer(skb) - + skb_network_header(skb); int found_rhdr = 0; *nexthdr = &ipv6_hdr(skb)->nexthdr; diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index a0962697a257..781dd3c99680 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -693,7 +693,7 @@ static void ndisc_recv_ns(struct sk_buff *skb) const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; u8 *lladdr = NULL; - u32 ndoptlen = skb->tail - (skb->transport_header + + u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + offsetof(struct nd_msg, opt)); struct ndisc_options ndopts; struct net_device *dev = skb->dev; @@ -853,7 +853,7 @@ static void ndisc_recv_na(struct sk_buff *skb) const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; u8 *lladdr = NULL; - u32 ndoptlen = skb->tail - (skb->transport_header + + u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + offsetof(struct nd_msg, opt)); struct ndisc_options ndopts; struct net_device *dev = skb->dev; @@ -1069,7 +1069,8 @@ static void ndisc_router_discovery(struct sk_buff *skb) __u8 * opt = (__u8 *)(ra_msg + 1); - optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg); + optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) - + sizeof(struct ra_msg); if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { ND_PRINTK(2, warn, "RA: source address is not link-local\n"); @@ -1346,7 +1347,7 @@ static void ndisc_redirect_rcv(struct sk_buff *skb) u8 *hdr; struct ndisc_options ndopts; struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb); - u32 ndoptlen = skb->tail - (skb->transport_header + + u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) + offsetof(struct rd_msg, opt)); #ifdef CONFIG_IPV6_NDISC_NODETYPE diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c index c2e73e647e44..ab92a3673fbb 100644 --- a/net/ipv6/output_core.c +++ b/net/ipv6/output_core.c @@ -40,7 +40,8 @@ int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) u16 offset = sizeof(struct ipv6hdr); struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); - unsigned int packet_len = skb->tail - skb->network_header; + unsigned int packet_len = skb_tail_pointer(skb) - + skb_network_header(skb); int found_rhdr = 0; *nexthdr = &ipv6_hdr(skb)->nexthdr; diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index eedff8ccded5..4f8886aa8429 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -1132,7 +1132,8 @@ static int rawv6_ioctl(struct sock *sk, int cmd, unsigned long arg) spin_lock_bh(&sk->sk_receive_queue.lock); skb = skb_peek(&sk->sk_receive_queue); if (skb != NULL) - amount = skb->tail - skb->transport_header; + amount = skb_tail_pointer(skb) - + skb_transport_header(skb); spin_unlock_bh(&sk->sk_receive_queue.lock); return put_user(amount, (int __user *)arg); } diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 194c3cde1536..2b874185ebb2 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1649,7 +1649,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu int optlen, on_link; u8 *lladdr; - optlen = skb->tail - skb->transport_header; + optlen = skb_tail_pointer(skb) - skb_transport_header(skb); optlen -= sizeof(*msg); if (optlen < 0) {