[PATCH 0/9] Netfilter fixes for net

[PATCH 0/9] Netfilter fixes for net

[Pablo Neira Ayuso]

Hi David,

The following patchset contains Netfilter fixes for your net tree:

1) Remove a direct dependency with IPv6 introduced by the
   sip_external_media feature, from Alin Nastac.

2) Fix bogus ENOENT when removing interval elements from set.

3) Set transport_header from br_netfilter to mimic the stack
   behaviour, this partially fixes a checksum validation bug
   from the SCTP connection tracking, from Xin Long.

4) Fix undefined reference to symbol in xt_TEE, due to missing
   Kconfig dependencies, from Arnd Bergmann.

5) Check for NULL in skb_header_pointer() calls in ip6t_shr,
   from Kangjie Lu.

6) Fix bogus EBUSY when removing an existing conntrack helper from
   a transaction.

7) Fix module autoload of the redirect extension.

8) Remove duplicated transition in flowtable diagram in the existing
   documentation.

9) Missing .release_ops call from error path in newrule() which
   results module refcount leak, from Taehee Yoo.

You can pull these changes from:

  git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git

Thanks!

----------------------------------------------------------------

The following changes since commit 4ec850e5dfec092b26cf3b7d5a6c9e444ea4babd:

  net: dwmac-sun8i: fix a missing check of of_get_phy_mode (2019-03-12 14:52:00 -0700)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git HEAD

for you to fetch changes up to b25a31bf0ca091aa8bdb9ab329b0226257568bbe:

  netfilter: nf_tables: add missing ->release_ops() in error path of newrule() (2019-03-20 08:32:58 +0100)

----------------------------------------------------------------
Alin Nastac (1):
      netfilter: nf_conntrack_sip: remove direct dependency on IPv6

Arnd Bergmann (1):
      netfilter: fix NETFILTER_XT_TARGET_TEE dependencies

Kangjie Lu (1):
      netfilter: ip6t_srh: fix NULL pointer dereferences

Pablo Neira Ayuso (4):
      netfilter: nft_set_rbtree: check for inactive element after flag mismatch
      netfilter: nf_tables: bogus EBUSY in helper removal from transaction
      netfilter: nft_redir: fix module autoload with ip4
      netfilter: nf_flowtable: remove duplicated transition in diagram

Taehee Yoo (1):
      netfilter: nf_tables: add missing ->release_ops() in error path of newrule()

Xin Long (1):
      netfilter: bridge: set skb transport_header before entering NF_INET_PRE_ROUTING

 Documentation/networking/nf_flowtable.txt |  8 +++----
 net/bridge/br_netfilter_hooks.c           |  1 +
 net/bridge/br_netfilter_ipv6.c            |  2 ++
 net/ipv6/netfilter/ip6t_srh.c             |  6 +++++
 net/netfilter/Kconfig                     |  1 +
 net/netfilter/nf_conntrack_sip.c          | 37 +++++++++++++------------------
 net/netfilter/nf_tables_api.c             |  5 ++++-
 net/netfilter/nft_objref.c                | 19 +++++++++++++---
 net/netfilter/nft_redir.c                 |  2 +-
 net/netfilter/nft_set_rbtree.c            |  7 +++---
 10 files changed, 54 insertions(+), 34 deletions(-)

[PATCH 1/9] netfilter: nf_conntrack_sip: remove direct dependency on IPv6

[Pablo Neira Ayuso]

From: Alin Nastac <alin.nastac@gmail.com>

Previous implementation was not usable with CONFIG_IPV6=m.

Fixes: a3419ce3356c ("netfilter: nf_conntrack_sip: add sip_external_media logic")
Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_conntrack_sip.c | 37 ++++++++++++++++---------------------
 1 file changed, 16 insertions(+), 21 deletions(-)

diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
index f067c6b50857..39fcc1ed18f3 100644
--- a/net/netfilter/nf_conntrack_sip.c
+++ b/net/netfilter/nf_conntrack_sip.c
@@ -20,9 +20,9 @@
 #include <linux/udp.h>
 #include <linux/tcp.h>
 #include <linux/netfilter.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6.h>
 
-#include <net/route.h>
-#include <net/ip6_route.h>
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_core.h>
 #include <net/netfilter/nf_conntrack_expect.h>
@@ -871,38 +871,33 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
 	} else if (sip_external_media) {
 		struct net_device *dev = skb_dst(skb)->dev;
 		struct net *net = dev_net(dev);
-		struct rtable *rt;
-		struct flowi4 fl4 = {};
-#if IS_ENABLED(CONFIG_IPV6)
-		struct flowi6 fl6 = {};
-#endif
+		struct flowi fl;
 		struct dst_entry *dst = NULL;
 
+		memset(&fl, 0, sizeof(fl));
+
 		switch (nf_ct_l3num(ct)) {
 			case NFPROTO_IPV4:
-				fl4.daddr = daddr->ip;
-				rt = ip_route_output_key(net, &fl4);
-				if (!IS_ERR(rt))
-					dst = &rt->dst;
+				fl.u.ip4.daddr = daddr->ip;
+				nf_ip_route(net, &dst, &fl, false);
 				break;
 
-#if IS_ENABLED(CONFIG_IPV6)
 			case NFPROTO_IPV6:
-				fl6.daddr = daddr->in6;
-				dst = ip6_route_output(net, NULL, &fl6);
-				if (dst->error) {
-					dst_release(dst);
-					dst = NULL;
-				}
+				fl.u.ip6.daddr = daddr->in6;
+				nf_ip6_route(net, &dst, &fl, false);
 				break;
-#endif
 		}
 
 		/* Don't predict any conntracks when media endpoint is reachable
 		 * through the same interface as the signalling peer.
 		 */
-		if (dst && dst->dev == dev)
-			return NF_ACCEPT;
+		if (dst) {
+			bool external_media = (dst->dev == dev);
+
+			dst_release(dst);
+			if (external_media)
+				return NF_ACCEPT;
+		}
 	}
 
 	/* We need to check whether the registration exists before attempting
-- 
2.11.0

[PATCH 2/9] netfilter: nft_set_rbtree: check for inactive element after flag mismatch

[Pablo Neira Ayuso]

Otherwise, we hit bogus ENOENT when removing elements.

Fixes: e701001e7cbe ("netfilter: nft_rbtree: allow adjacent intervals with dynamic updates")
Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_set_rbtree.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index fa61208371f8..321a0036fdf5 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -308,10 +308,6 @@ static void *nft_rbtree_deactivate(const struct net *net,
 		else if (d > 0)
 			parent = parent->rb_right;
 		else {
-			if (!nft_set_elem_active(&rbe->ext, genmask)) {
-				parent = parent->rb_left;
-				continue;
-			}
 			if (nft_rbtree_interval_end(rbe) &&
 			    !nft_rbtree_interval_end(this)) {
 				parent = parent->rb_left;
@@ -320,6 +316,9 @@ static void *nft_rbtree_deactivate(const struct net *net,
 				   nft_rbtree_interval_end(this)) {
 				parent = parent->rb_right;
 				continue;
+			} else if (!nft_set_elem_active(&rbe->ext, genmask)) {
+				parent = parent->rb_left;
+				continue;
 			}
 			nft_rbtree_flush(net, set, rbe);
 			return rbe;
-- 
2.11.0

[PATCH 3/9] netfilter: bridge: set skb transport_header before entering NF_INET_PRE_ROUTING

[Pablo Neira Ayuso]

From: Xin Long <lucien.xin@gmail.com>

Since Commit 21d1196a35f5 ("ipv4: set transport header earlier"),
skb->transport_header has been always set before entering INET
netfilter. This patch is to set skb->transport_header for bridge
before entering INET netfilter by bridge-nf-call-iptables.

It also fixes an issue that sctp_error() couldn't compute a right
csum due to unset skb->transport_header.

Fixes: e6d8b64b34aa ("net: sctp: fix and consolidate SCTP checksumming code")
Reported-by: Li Shuang <shuali@redhat.com>
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/br_netfilter_hooks.c | 1 +
 net/bridge/br_netfilter_ipv6.c  | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c
index 9d34de68571b..22afa566cbce 100644
--- a/net/bridge/br_netfilter_hooks.c
+++ b/net/bridge/br_netfilter_hooks.c
@@ -502,6 +502,7 @@ static unsigned int br_nf_pre_routing(void *priv,
 	nf_bridge->ipv4_daddr = ip_hdr(skb)->daddr;
 
 	skb->protocol = htons(ETH_P_IP);
+	skb->transport_header = skb->network_header + ip_hdr(skb)->ihl * 4;
 
 	NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, state->net, state->sk, skb,
 		skb->dev, NULL,
diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
index 564710f88f93..e88d6641647b 100644
--- a/net/bridge/br_netfilter_ipv6.c
+++ b/net/bridge/br_netfilter_ipv6.c
@@ -235,6 +235,8 @@ unsigned int br_nf_pre_routing_ipv6(void *priv,
 	nf_bridge->ipv6_daddr = ipv6_hdr(skb)->daddr;
 
 	skb->protocol = htons(ETH_P_IPV6);
+	skb->transport_header = skb->network_header + sizeof(struct ipv6hdr);
+
 	NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, state->net, state->sk, skb,
 		skb->dev, NULL,
 		br_nf_pre_routing_finish_ipv6);
-- 
2.11.0

[PATCH 4/9] netfilter: fix NETFILTER_XT_TARGET_TEE dependencies

[Pablo Neira Ayuso]

From: Arnd Bergmann <arnd@arndb.de>

With NETFILTER_XT_TARGET_TEE=y and IP6_NF_IPTABLES=m, we get a link
error when referencing the NF_DUP_IPV6 module:

net/netfilter/xt_TEE.o: In function `tee_tg6':
xt_TEE.c:(.text+0x14): undefined reference to `nf_dup_ipv6'

The problem here is the 'select NF_DUP_IPV6 if IP6_NF_IPTABLES'
that forces NF_DUP_IPV6 to be =m as well rather than setting it
to =y as was intended here. Adding a soft dependency on
IP6_NF_IPTABLES avoids that broken configuration.

Fixes: 5d400a4933e8 ("netfilter: Kconfig: Change select IPv6 dependencies")
Cc: Máté Eckl <ecklm94@gmail.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Link: https://patchwork.ozlabs.org/patch/999498/
Link: https://lore.kernel.org/patchwork/patch/960062/
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index d43ffb09939b..6548271209a0 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -1007,6 +1007,7 @@ config NETFILTER_XT_TARGET_TEE
 	depends on NETFILTER_ADVANCED
 	depends on IPV6 || IPV6=n
 	depends on !NF_CONNTRACK || NF_CONNTRACK
+	depends on IP6_NF_IPTABLES || !IP6_NF_IPTABLES
 	select NF_DUP_IPV4
 	select NF_DUP_IPV6 if IP6_NF_IPTABLES
 	---help---
-- 
2.11.0

[PATCH 5/9] netfilter: ip6t_srh: fix NULL pointer dereferences

[Pablo Neira Ayuso]

From: Kangjie Lu <kjlu@umn.edu>

skb_header_pointer may return NULL. The current code dereference
its return values without a NULL check.

The fix inserts the checks to avoid NULL pointer dereferences.

Fixes: 202a8ff545cc ("netfilter: add IPv6 segment routing header 'srh' match")
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv6/netfilter/ip6t_srh.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/ipv6/netfilter/ip6t_srh.c b/net/ipv6/netfilter/ip6t_srh.c
index 1059894a6f4c..4cb83fb69844 100644
--- a/net/ipv6/netfilter/ip6t_srh.c
+++ b/net/ipv6/netfilter/ip6t_srh.c
@@ -210,6 +210,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par)
 		psidoff = srhoff + sizeof(struct ipv6_sr_hdr) +
 			  ((srh->segments_left + 1) * sizeof(struct in6_addr));
 		psid = skb_header_pointer(skb, psidoff, sizeof(_psid), &_psid);
+		if (!psid)
+			return false;
 		if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_PSID,
 				ipv6_masked_addr_cmp(psid, &srhinfo->psid_msk,
 						     &srhinfo->psid_addr)))
@@ -223,6 +225,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par)
 		nsidoff = srhoff + sizeof(struct ipv6_sr_hdr) +
 			  ((srh->segments_left - 1) * sizeof(struct in6_addr));
 		nsid = skb_header_pointer(skb, nsidoff, sizeof(_nsid), &_nsid);
+		if (!nsid)
+			return false;
 		if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_NSID,
 				ipv6_masked_addr_cmp(nsid, &srhinfo->nsid_msk,
 						     &srhinfo->nsid_addr)))
@@ -233,6 +237,8 @@ static bool srh1_mt6(const struct sk_buff *skb, struct xt_action_param *par)
 	if (srhinfo->mt_flags & IP6T_SRH_LSID) {
 		lsidoff = srhoff + sizeof(struct ipv6_sr_hdr);
 		lsid = skb_header_pointer(skb, lsidoff, sizeof(_lsid), &_lsid);
+		if (!lsid)
+			return false;
 		if (NF_SRH_INVF(srhinfo, IP6T_SRH_INV_LSID,
 				ipv6_masked_addr_cmp(lsid, &srhinfo->lsid_msk,
 						     &srhinfo->lsid_addr)))
-- 
2.11.0

[PATCH 6/9] netfilter: nf_tables: bogus EBUSY in helper removal from transaction

[Pablo Neira Ayuso]

Proper use counter updates when activating and deactivating the object,
otherwise, this hits bogus EBUSY error.

Fixes: cd5125d8f518 ("netfilter: nf_tables: split set destruction in deactivate and destroy phase")
Reported-by: Laura Garcia <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_objref.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/net/netfilter/nft_objref.c b/net/netfilter/nft_objref.c
index 457a9ceb46af..8dfa798ea683 100644
--- a/net/netfilter/nft_objref.c
+++ b/net/netfilter/nft_objref.c
@@ -65,21 +65,34 @@ static int nft_objref_dump(struct sk_buff *skb, const struct nft_expr *expr)
 	return -1;
 }
 
-static void nft_objref_destroy(const struct nft_ctx *ctx,
-			       const struct nft_expr *expr)
+static void nft_objref_deactivate(const struct nft_ctx *ctx,
+				  const struct nft_expr *expr,
+				  enum nft_trans_phase phase)
 {
 	struct nft_object *obj = nft_objref_priv(expr);
 
+	if (phase == NFT_TRANS_COMMIT)
+		return;
+
 	obj->use--;
 }
 
+static void nft_objref_activate(const struct nft_ctx *ctx,
+				const struct nft_expr *expr)
+{
+	struct nft_object *obj = nft_objref_priv(expr);
+
+	obj->use++;
+}
+
 static struct nft_expr_type nft_objref_type;
 static const struct nft_expr_ops nft_objref_ops = {
 	.type		= &nft_objref_type,
 	.size		= NFT_EXPR_SIZE(sizeof(struct nft_object *)),
 	.eval		= nft_objref_eval,
 	.init		= nft_objref_init,
-	.destroy	= nft_objref_destroy,
+	.activate	= nft_objref_activate,
+	.deactivate	= nft_objref_deactivate,
 	.dump		= nft_objref_dump,
 };
 
-- 
2.11.0

[PATCH 7/9] netfilter: nft_redir: fix module autoload with ip4

[Pablo Neira Ayuso]

AF_INET4 does not exist.

Fixes: c78efc99c750 ("netfilter: nf_tables: nat: merge nft_redir protocol specific modules)"
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_redir.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/nft_redir.c b/net/netfilter/nft_redir.c
index f8092926f704..a340cd8a751b 100644
--- a/net/netfilter/nft_redir.c
+++ b/net/netfilter/nft_redir.c
@@ -233,5 +233,5 @@ module_exit(nft_redir_module_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
-MODULE_ALIAS_NFT_AF_EXPR(AF_INET4, "redir");
+MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "redir");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "redir");
-- 
2.11.0

[PATCH 8/9] netfilter: nf_flowtable: remove duplicated transition in diagram

[Pablo Neira Ayuso]

No direct transition from prerouting to forward hook, routing lookup
needs to happen first.

Fixes: 19b351f16fd9 ("netfilter: add flowtable documentation")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 Documentation/networking/nf_flowtable.txt | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Documentation/networking/nf_flowtable.txt b/Documentation/networking/nf_flowtable.txt
index 54128c50d508..ca2136c76042 100644
--- a/Documentation/networking/nf_flowtable.txt
+++ b/Documentation/networking/nf_flowtable.txt
@@ -44,10 +44,10 @@ including the Netfilter hooks and the flowtable fastpath bypass.
      /         \    /          \     |Routing |   /            \
   -->  ingress  ---> prerouting ---> |decision|   | postrouting |--> neigh_xmit
      \_________/    \__________/     ----------   \____________/          ^
-       |      ^          |               |               ^                |
-   flowtable  |          |          ____\/___            |                |
-       |      |          |         /         \           |                |
-    __\/___   |          --------->| forward |------------                |
+       |      ^                          |               ^                |
+   flowtable  |                     ____\/___            |                |
+       |      |                    /         \           |                |
+    __\/___   |                    | forward |------------                |
     |-----|   |                    \_________/                            |
     |-----|   |                 'flow offload' rule                       |
     |-----|   |                   adds entry to                           |
-- 
2.11.0

[PATCH 9/9] netfilter: nf_tables: add missing ->release_ops() in error path of newrule()

[Pablo Neira Ayuso]

From: Taehee Yoo <ap420073@gmail.com>

->release_ops() callback releases resources and this is used in error path.
If nf_tables_newrule() fails after ->select_ops(), it should release
resources. but it can not call ->destroy() because that should be called
after ->init().
At this point, ->release_ops() should be used for releasing resources.

Test commands:
   modprobe -rv xt_tcpudp
   iptables-nft -I INPUT -m tcp   <-- error command
   lsmod

Result:
   Module                  Size  Used by
   xt_tcpudp              20480  2      <-- it should be 0

Fixes: b8e204006340 ("netfilter: nft_compat: use .release_ops and remove list of extension")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_tables_api.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 513f93118604..ef7772e976cc 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2806,8 +2806,11 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
 	nf_tables_rule_release(&ctx, rule);
 err1:
 	for (i = 0; i < n; i++) {
-		if (info[i].ops != NULL)
+		if (info[i].ops) {
 			module_put(info[i].ops->type->owner);
+			if (info[i].ops->type->release_ops)
+				info[i].ops->type->release_ops(info[i].ops);
+		}
 	}
 	kvfree(info);
 	return err;
-- 
2.11.0

Re: [PATCH 0/9] Netfilter fixes for net

[David Miller]

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Thu, 21 Mar 2019 12:28:36 +0100

> The following patchset contains Netfilter fixes for your net tree:
> 
> 1) Remove a direct dependency with IPv6 introduced by the
>    sip_external_media feature, from Alin Nastac.
> 
> 2) Fix bogus ENOENT when removing interval elements from set.
> 
> 3) Set transport_header from br_netfilter to mimic the stack
>    behaviour, this partially fixes a checksum validation bug
>    from the SCTP connection tracking, from Xin Long.
> 
> 4) Fix undefined reference to symbol in xt_TEE, due to missing
>    Kconfig dependencies, from Arnd Bergmann.
> 
> 5) Check for NULL in skb_header_pointer() calls in ip6t_shr,
>    from Kangjie Lu.
> 
> 6) Fix bogus EBUSY when removing an existing conntrack helper from
>    a transaction.
> 
> 7) Fix module autoload of the redirect extension.
> 
> 8) Remove duplicated transition in flowtable diagram in the existing
>    documentation.
> 
> 9) Missing .release_ops call from error path in newrule() which
>    results module refcount leak, from Taehee Yoo.
> 
> You can pull these changes from:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git

Pulled, thanks.