6.12-stable review patch. If anyone has any objections, please let me know.
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From: Florian Westphal fw@strlen.de
commit eaaff9b6702e99be5d79135f2afa9fc48a0d59e0 upstream.
In case the fib match is used from the input hook we can avoid the fib lookup if early demux assigned a socket for us: check that the input interface matches sk-cached one.
Rework the existing 'lo bypass' logic to first check sk, then for loopback interface type to elide the fib lookup.
This speeds up fib matching a little, before: 93.08 GBit/s (no rules at all) 75.1 GBit/s ("fib saddr . iif oif missing drop" in prerouting) 75.62 GBit/s ("fib saddr . iif oif missing drop" in input)
After: 92.48 GBit/s (no rules at all) 75.62 GBit/s (fib rule in prerouting) 90.37 GBit/s (fib rule in input).
Numbers for the 'no rules' and 'prerouting' are expected to closely match in-between runs, the 3rd/input test case exercises the the 'avoid lookup if cached ifindex in sk matches' case.
Test used iperf3 via veth interface, lo can't be used due to existing loopback test.
Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/net/netfilter/nft_fib.h | 21 +++++++++++++++++++++ net/ipv4/netfilter/nft_fib_ipv4.c | 11 +++++------ net/ipv6/netfilter/nft_fib_ipv6.c | 19 ++++++++++--------- 3 files changed, 36 insertions(+), 15 deletions(-)
--- a/include/net/netfilter/nft_fib.h +++ b/include/net/netfilter/nft_fib.h @@ -18,6 +18,27 @@ nft_fib_is_loopback(const struct sk_buff return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; }
+static inline bool nft_fib_can_skip(const struct nft_pktinfo *pkt) +{ + const struct net_device *indev = nft_in(pkt); + const struct sock *sk; + + switch (nft_hook(pkt)) { + case NF_INET_PRE_ROUTING: + case NF_INET_INGRESS: + case NF_INET_LOCAL_IN: + break; + default: + return false; + } + + sk = pkt->skb->sk; + if (sk && sk_fullsock(sk)) + return sk->sk_rx_dst_ifindex == indev->ifindex; + + return nft_fib_is_loopback(pkt->skb, indev); +} + int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr, bool reset); int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]); --- a/net/ipv4/netfilter/nft_fib_ipv4.c +++ b/net/ipv4/netfilter/nft_fib_ipv4.c @@ -70,6 +70,11 @@ void nft_fib4_eval(const struct nft_expr const struct net_device *oif; const struct net_device *found;
+ if (nft_fib_can_skip(pkt)) { + nft_fib_store_result(dest, priv, nft_in(pkt)); + return; + } + /* * Do not set flowi4_oif, it restricts results (for example, asking * for oif 3 will get RTN_UNICAST result even if the daddr exits @@ -84,12 +89,6 @@ void nft_fib4_eval(const struct nft_expr else oif = NULL;
- if (nft_hook(pkt) == NF_INET_PRE_ROUTING && - nft_fib_is_loopback(pkt->skb, nft_in(pkt))) { - nft_fib_store_result(dest, priv, nft_in(pkt)); - return; - } - iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph); if (!iph) { regs->verdict.code = NFT_BREAK; --- a/net/ipv6/netfilter/nft_fib_ipv6.c +++ b/net/ipv6/netfilter/nft_fib_ipv6.c @@ -170,6 +170,11 @@ void nft_fib6_eval(const struct nft_expr struct rt6_info *rt; int lookup_flags;
+ if (nft_fib_can_skip(pkt)) { + nft_fib_store_result(dest, priv, nft_in(pkt)); + return; + } + if (priv->flags & NFTA_FIB_F_IIF) oif = nft_in(pkt); else if (priv->flags & NFTA_FIB_F_OIF) @@ -181,17 +186,13 @@ void nft_fib6_eval(const struct nft_expr return; }
- lookup_flags = nft_fib6_flowi_init(&fl6, priv, pkt, oif, iph); - - if (nft_hook(pkt) == NF_INET_PRE_ROUTING || - nft_hook(pkt) == NF_INET_INGRESS) { - if (nft_fib_is_loopback(pkt->skb, nft_in(pkt)) || - nft_fib_v6_skip_icmpv6(pkt->skb, pkt->tprot, iph)) { - nft_fib_store_result(dest, priv, nft_in(pkt)); - return; - } + if (nft_fib_v6_skip_icmpv6(pkt->skb, pkt->tprot, iph)) { + nft_fib_store_result(dest, priv, nft_in(pkt)); + return; }
+ lookup_flags = nft_fib6_flowi_init(&fl6, priv, pkt, oif, iph); + *dest = 0; rt = (void *)ip6_route_lookup(nft_net(pkt), &fl6, pkt->skb, lookup_flags);