Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2018-07-01

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) A bpf_fib_lookup() helper fix to change the API before freeze to
   return an encoding of the FIB lookup result and return the nexthop
   device index in the params struct (instead of device index as return
   code that we had before), from David.

2) Various BPF JIT fixes to address syzkaller fallout, that is, do not
   reject progs when set_memory_*() fails since it could still be RO.
   Also arm32 JIT was not using bpf_jit_binary_lock_ro() API which was
   an issue, and a memory leak in s390 JIT found during review, from
   Daniel.

3) Multiple fixes for sockmap/hash to address most of the syzkaller
   triggered bugs. Usage with IPv6 was crashing, a GPF in bpf_tcp_close(),
   a missing sock_map_release() routine to hook up to callbacks, and a
   fix for an omitted bucket lock in sock_close(), from John.

4) Two bpftool fixes to remove duplicated error message on program load,
   and another one to close the libbpf object after program load. One
   additional fix for nfp driver's BPF offload to avoid stopping offload
   completely if replace of program failed, from Jakub.

5) Couple of BPF selftest fixes that bail out in some of the test
   scripts if the user does not have the right privileges, from Jeffrin.

6) Fixes in test_bpf for s390 when CONFIG_BPF_JIT_ALWAYS_ON is set
   where we need to set the flag that some of the test cases are expected
   to fail, from Kleber.

7) Fix to detangle BPF_LIRC_MODE2 dependency from CONFIG_CGROUP_BPF
   since it has no relation to it and lirc2 users often have configs
   without cgroups enabled and thus would not be able to use it, from Sean.

8) Fix a selftest failure in sockmap by removing a useless setrlimit()
   call that would set a too low limit where at the same time we are
   already including bpf_rlimit.h that does the job, from Yonghong.

9) Fix BPF selftest config with missing missing NET_SCHED, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 54 insertions, 32 deletions

diff --git a/net/core/filter.c b/net/core/filter.c
index e7f12e9f598c..0ca6907d7efe 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4073,8 +4073,9 @@ static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
 	params->h_vlan_TCI = 0;
 	params->h_vlan_proto = 0;
+	params->ifindex = dev->ifindex;
 
-	return dev->ifindex;
+	return 0;
 }
 #endif
 
@@ -4098,7 +4099,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	/* verify forwarding is enabled on this interface */
 	in_dev = __in_dev_get_rcu(dev);
 	if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
-		return 0;
+		return BPF_FIB_LKUP_RET_FWD_DISABLED;
 
 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
 		fl4.flowi4_iif = 1;
@@ -4123,7 +4124,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 
 		tb = fib_get_table(net, tbid);
 		if (unlikely(!tb))
-			return 0;
+			return BPF_FIB_LKUP_RET_NOT_FWDED;
 
 		err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
 	} else {
@@ -4135,8 +4136,20 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 		err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
 	}
 
-	if (err || res.type != RTN_UNICAST)
-		return 0;
+	if (err) {
+		/* map fib lookup errors to RTN_ type */
+		if (err == -EINVAL)
+			return BPF_FIB_LKUP_RET_BLACKHOLE;
+		if (err == -EHOSTUNREACH)
+			return BPF_FIB_LKUP_RET_UNREACHABLE;
+		if (err == -EACCES)
+			return BPF_FIB_LKUP_RET_PROHIBIT;
+
+		return BPF_FIB_LKUP_RET_NOT_FWDED;
+	}
+
+	if (res.type != RTN_UNICAST)
+		return BPF_FIB_LKUP_RET_NOT_FWDED;
 
 	if (res.fi->fib_nhs > 1)
 		fib_select_path(net, &res, &fl4, NULL);
@@ -4144,19 +4157,16 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	if (check_mtu) {
 		mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
 		if (params->tot_len > mtu)
-			return 0;
+			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
 	}
 
 	nh = &res.fi->fib_nh[res.nh_sel];
 
 	/* do not handle lwt encaps right now */
 	if (nh->nh_lwtstate)
-		return 0;
+		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
 
 	dev = nh->nh_dev;
-	if (unlikely(!dev))
-		return 0;
-
 	if (nh->nh_gw)
 		params->ipv4_dst = nh->nh_gw;
 
@@ -4166,10 +4176,10 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	 * rcu_read_lock_bh is not needed here
 	 */
 	neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst);
-	if (neigh)
-		return bpf_fib_set_fwd_params(params, neigh, dev);
+	if (!neigh)
+		return BPF_FIB_LKUP_RET_NO_NEIGH;
 
-	return 0;
+	return bpf_fib_set_fwd_params(params, neigh, dev);
 }
 #endif
 
@@ -4190,7 +4200,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 
 	/* link local addresses are never forwarded */
 	if (rt6_need_strict(dst) || rt6_need_strict(src))
-		return 0;
+		return BPF_FIB_LKUP_RET_NOT_FWDED;
 
 	dev = dev_get_by_index_rcu(net, params->ifindex);
 	if (unlikely(!dev))
@@ -4198,7 +4208,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 
 	idev = __in6_dev_get_safely(dev);
 	if (unlikely(!idev || !net->ipv6.devconf_all->forwarding))
-		return 0;
+		return BPF_FIB_LKUP_RET_FWD_DISABLED;
 
 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
 		fl6.flowi6_iif = 1;
@@ -4225,7 +4235,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 
 		tb = ipv6_stub->fib6_get_table(net, tbid);
 		if (unlikely(!tb))
-			return 0;
+			return BPF_FIB_LKUP_RET_NOT_FWDED;
 
 		f6i = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, strict);
 	} else {
@@ -4238,11 +4248,23 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	}
 
 	if (unlikely(IS_ERR_OR_NULL(f6i) || f6i == net->ipv6.fib6_null_entry))
-		return 0;
+		return BPF_FIB_LKUP_RET_NOT_FWDED;
+
+	if (unlikely(f6i->fib6_flags & RTF_REJECT)) {
+		switch (f6i->fib6_type) {
+		case RTN_BLACKHOLE:
+			return BPF_FIB_LKUP_RET_BLACKHOLE;
+		case RTN_UNREACHABLE:
+			return BPF_FIB_LKUP_RET_UNREACHABLE;
+		case RTN_PROHIBIT:
+			return BPF_FIB_LKUP_RET_PROHIBIT;
+		default:
+			return BPF_FIB_LKUP_RET_NOT_FWDED;
+		}
+	}
 
-	if (unlikely(f6i->fib6_flags & RTF_REJECT ||
-	    f6i->fib6_type != RTN_UNICAST))
-		return 0;
+	if (f6i->fib6_type != RTN_UNICAST)
+		return BPF_FIB_LKUP_RET_NOT_FWDED;
 
 	if (f6i->fib6_nsiblings && fl6.flowi6_oif == 0)
 		f6i = ipv6_stub->fib6_multipath_select(net, f6i, &fl6,
@@ -4252,11 +4274,11 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	if (check_mtu) {
 		mtu = ipv6_stub->ip6_mtu_from_fib6(f6i, dst, src);
 		if (params->tot_len > mtu)
-			return 0;
+			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
 	}
 
 	if (f6i->fib6_nh.nh_lwtstate)
-		return 0;
+		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
 
 	if (f6i->fib6_flags & RTF_GATEWAY)
 		*dst = f6i->fib6_nh.nh_gw;
@@ -4270,10 +4292,10 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
 	 */
 	neigh = ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128,
 				      ndisc_hashfn, dst, dev);
-	if (neigh)
-		return bpf_fib_set_fwd_params(params, neigh, dev);
+	if (!neigh)
+		return BPF_FIB_LKUP_RET_NO_NEIGH;
 
-	return 0;
+	return bpf_fib_set_fwd_params(params, neigh, dev);
 }
 #endif
 
@@ -4315,7 +4337,7 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
 {
 	struct net *net = dev_net(skb->dev);
-	int index = -EAFNOSUPPORT;
+	int rc = -EAFNOSUPPORT;
 
 	if (plen < sizeof(*params))
 		return -EINVAL;
@@ -4326,25 +4348,25 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
 	switch (params->family) {
 #if IS_ENABLED(CONFIG_INET)
 	case AF_INET:
-		index = bpf_ipv4_fib_lookup(net, params, flags, false);
+		rc = bpf_ipv4_fib_lookup(net, params, flags, false);
 		break;
 #endif
 #if IS_ENABLED(CONFIG_IPV6)
 	case AF_INET6:
-		index = bpf_ipv6_fib_lookup(net, params, flags, false);
+		rc = bpf_ipv6_fib_lookup(net, params, flags, false);
 		break;
 #endif
 	}
 
-	if (index > 0) {
+	if (!rc) {
 		struct net_device *dev;
 
-		dev = dev_get_by_index_rcu(net, index);
+		dev = dev_get_by_index_rcu(net, params->ifindex);
 		if (!is_skb_forwardable(dev, skb))
-			index = 0;
+			rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
 	}
 
-	return index;
+	return rc;
 }
 
 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {