diff options
| author | Pablo M. Bermudo Garay <pablombg@gmail.com> | 2017-07-21 01:54:37 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-07-31 19:01:39 +0200 |
| commit | f347ec852c7a83e1803192d2c1fce4e42e0715a5 (patch) | |
| tree | 1edb8892ad7ed553c91042b04019443f5eebea88 /net/ipv4/netfilter | |
| parent | 784b4e612d42a2b7578d7fab2ed78940e10536bc (diff) | |
netfilter: nf_tables: fib: use skb_header_pointer
This is a preparatory patch for adding fib support to the netdev family.
The netdev family receives the packets from ingress hook. At this point
we have no guarantee that the ip header is linear. So this patch
replaces ip_hdr with skb_header_pointer in order to address that
possible situation.
Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4/netfilter')
| -rw-r--r-- | net/ipv4/netfilter/nft_fib_ipv4.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c index de3681df2ce7..e50976e3c213 100644 --- a/net/ipv4/netfilter/nft_fib_ipv4.c +++ b/net/ipv4/netfilter/nft_fib_ipv4.c @@ -32,9 +32,10 @@ void nft_fib4_eval_type(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { const struct nft_fib *priv = nft_expr_priv(expr); + int noff = skb_network_offset(pkt->skb); u32 *dst = ®s->data[priv->dreg]; const struct net_device *dev = NULL; - const struct iphdr *iph; + struct iphdr *iph, _iph; __be32 addr; if (priv->flags & NFTA_FIB_F_IIF) @@ -42,7 +43,12 @@ void nft_fib4_eval_type(const struct nft_expr *expr, struct nft_regs *regs, else if (priv->flags & NFTA_FIB_F_OIF) dev = nft_out(pkt); - iph = ip_hdr(pkt->skb); + iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph); + if (!iph) { + regs->verdict.code = NFT_BREAK; + return; + } + if (priv->flags & NFTA_FIB_F_DADDR) addr = iph->daddr; else @@ -61,8 +67,9 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { const struct nft_fib *priv = nft_expr_priv(expr); + int noff = skb_network_offset(pkt->skb); u32 *dest = ®s->data[priv->dreg]; - const struct iphdr *iph; + struct iphdr *iph, _iph; struct fib_result res; struct flowi4 fl4 = { .flowi4_scope = RT_SCOPE_UNIVERSE, @@ -95,7 +102,12 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, return; } - iph = ip_hdr(pkt->skb); + iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph); + if (!iph) { + regs->verdict.code = NFT_BREAK; + return; + } + if (ipv4_is_zeronet(iph->saddr)) { if (ipv4_is_lbcast(iph->daddr) || ipv4_is_local_multicast(iph->daddr)) { |