[PATCH AUTOSEL 5.1 12/70] netfilter: nft_fib: Fix existence check support

From: Sasha Levin
Date: Sat Jun 08 2019 - 07:59:36 EST


From: Phil Sutter <phil@xxxxxx>

[ Upstream commit e633508a95289489d28faacb68b32c3e7e68ef6f ]

NFTA_FIB_F_PRESENT flag was not always honored since eval functions did
not call nft_fib_store_result in all cases.

Given that in all callsites there is a struct net_device pointer
available which holds the interface data to be stored in destination
register, simplify nft_fib_store_result() to just accept that pointer
instead of the nft_pktinfo pointer and interface index. This also
allows to drop the index to interface lookup previously needed to get
the name associated with given index.

Fixes: 055c4b34b94f6 ("netfilter: nft_fib: Support existence check")
Signed-off-by: Phil Sutter <phil@xxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/net/netfilter/nft_fib.h | 2 +-
net/ipv4/netfilter/nft_fib_ipv4.c | 23 +++--------------------
net/ipv6/netfilter/nft_fib_ipv6.c | 16 ++--------------
net/netfilter/nft_fib.c | 6 +++---
4 files changed, 9 insertions(+), 38 deletions(-)

diff --git a/include/net/netfilter/nft_fib.h b/include/net/netfilter/nft_fib.h
index a88f92737308..e4c4d8eaca8c 100644
--- a/include/net/netfilter/nft_fib.h
+++ b/include/net/netfilter/nft_fib.h
@@ -34,5 +34,5 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs,
const struct nft_pktinfo *pkt);

void nft_fib_store_result(void *reg, const struct nft_fib *priv,
- const struct nft_pktinfo *pkt, int index);
+ const struct net_device *dev);
#endif
diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c
index 94eb25bc8d7e..c8888e52591f 100644
--- a/net/ipv4/netfilter/nft_fib_ipv4.c
+++ b/net/ipv4/netfilter/nft_fib_ipv4.c
@@ -58,11 +58,6 @@ void nft_fib4_eval_type(const struct nft_expr *expr, struct nft_regs *regs,
}
EXPORT_SYMBOL_GPL(nft_fib4_eval_type);

-static int get_ifindex(const struct net_device *dev)
-{
- return dev ? dev->ifindex : 0;
-}
-
void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
@@ -94,8 +89,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,

if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {
- nft_fib_store_result(dest, priv, pkt,
- nft_in(pkt)->ifindex);
+ nft_fib_store_result(dest, priv, nft_in(pkt));
return;
}

@@ -108,8 +102,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
if (ipv4_is_zeronet(iph->saddr)) {
if (ipv4_is_lbcast(iph->daddr) ||
ipv4_is_local_multicast(iph->daddr)) {
- nft_fib_store_result(dest, priv, pkt,
- get_ifindex(pkt->skb->dev));
+ nft_fib_store_result(dest, priv, pkt->skb->dev);
return;
}
}
@@ -150,17 +143,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
found = oif;
}

- switch (priv->result) {
- case NFT_FIB_RESULT_OIF:
- *dest = found->ifindex;
- break;
- case NFT_FIB_RESULT_OIFNAME:
- strncpy((char *)dest, found->name, IFNAMSIZ);
- break;
- default:
- WARN_ON_ONCE(1);
- break;
- }
+ nft_fib_store_result(dest, priv, found);
}
EXPORT_SYMBOL_GPL(nft_fib4_eval);

diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c
index 73cdc0bc63f7..ec068b0cffca 100644
--- a/net/ipv6/netfilter/nft_fib_ipv6.c
+++ b/net/ipv6/netfilter/nft_fib_ipv6.c
@@ -169,8 +169,7 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs,

if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {
- nft_fib_store_result(dest, priv, pkt,
- nft_in(pkt)->ifindex);
+ nft_fib_store_result(dest, priv, nft_in(pkt));
return;
}

@@ -187,18 +186,7 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs,
if (oif && oif != rt->rt6i_idev->dev)
goto put_rt_err;

- switch (priv->result) {
- case NFT_FIB_RESULT_OIF:
- *dest = rt->rt6i_idev->dev->ifindex;
- break;
- case NFT_FIB_RESULT_OIFNAME:
- strncpy((char *)dest, rt->rt6i_idev->dev->name, IFNAMSIZ);
- break;
- default:
- WARN_ON_ONCE(1);
- break;
- }
-
+ nft_fib_store_result(dest, priv, rt->rt6i_idev->dev);
put_rt_err:
ip6_rt_put(rt);
}
diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c
index 21df8cccea65..77f00a99dfab 100644
--- a/net/netfilter/nft_fib.c
+++ b/net/netfilter/nft_fib.c
@@ -135,17 +135,17 @@ int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr)
EXPORT_SYMBOL_GPL(nft_fib_dump);

void nft_fib_store_result(void *reg, const struct nft_fib *priv,
- const struct nft_pktinfo *pkt, int index)
+ const struct net_device *dev)
{
- struct net_device *dev;
u32 *dreg = reg;
+ int index;

switch (priv->result) {
case NFT_FIB_RESULT_OIF:
+ index = dev ? dev->ifindex : 0;
*dreg = (priv->flags & NFTA_FIB_F_PRESENT) ? !!index : index;
break;
case NFT_FIB_RESULT_OIFNAME:
- dev = dev_get_by_index_rcu(nft_net(pkt), index);
if (priv->flags & NFTA_FIB_F_PRESENT)
*dreg = !!dev;
else
--
2.20.1