[PATCH net 0/5] Netfilter fixes for net

[PATCH net 0/5] Netfilter fixes for net

[Pablo Neira Ayuso]

Hi,

The following patchset contains Netfilter fixes for net:

1) Fix insufficient validation of IPSET_ATTR_IPADDR_IPV6 reported
   by syzbot.

2) Remove spurious reports on nf_tables when lockdep gets disabled,
   from Florian Westphal.

3) Fix memleak in the error path of error path of
   ip_vs_control_net_init(), from Wang Hai.

4) Fix missing control data in flow dissector, otherwise IP address
   matching in hardware offload infra does not work.

5) Fix hardware offload match on prefix IP address when userspace
   does not send a bitwise expression to represent the prefix.

Please, pull these changes from:

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

Thanks Jakub.

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

The following changes since commit 90cf87d16bd566cff40c2bc8e32e6d4cd3af23f0:

  enetc: Let the hardware auto-advance the taprio base-time of 0 (2020-11-25 12:36:27 -0800)

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 a5d45bc0dc50f9dd83703510e9804d813a9cac32:

  netfilter: nftables_offload: build mask based from the matching bytes (2020-11-27 12:10:47 +0100)

----------------------------------------------------------------
Eric Dumazet (1):
      netfilter: ipset: prevent uninit-value in hash_ip6_add

Florian Westphal (1):
      netfilter: nf_tables: avoid false-postive lockdep splat

Pablo Neira Ayuso (2):
      netfilter: nftables_offload: set address type in control dissector
      netfilter: nftables_offload: build mask based from the matching bytes

Wang Hai (1):
      ipvs: fix possible memory leak in ip_vs_control_net_init

 include/net/netfilter/nf_tables_offload.h |  7 ++++
 net/netfilter/ipset/ip_set_core.c         |  3 +-
 net/netfilter/ipvs/ip_vs_ctl.c            | 31 +++++++++++---
 net/netfilter/nf_tables_api.c             |  3 +-
 net/netfilter/nf_tables_offload.c         | 17 ++++++++
 net/netfilter/nft_cmp.c                   |  8 ++--
 net/netfilter/nft_meta.c                  | 16 +++----
 net/netfilter/nft_payload.c               | 70 +++++++++++++++++++++++--------
 8 files changed, 117 insertions(+), 38 deletions(-)

[PATCH net 1/5] netfilter: ipset: prevent uninit-value in hash_ip6_add

[Pablo Neira Ayuso]

From: Eric Dumazet <edumazet@google.com>

syzbot found that we are not validating user input properly
before copying 16 bytes [1].

Using NLA_BINARY in ipaddr_policy[] for IPv6 address is not correct,
since it ensures at most 16 bytes were provided.

We should instead make sure user provided exactly 16 bytes.

In old kernels (before v4.20), fix would be to remove the NLA_BINARY,
since NLA_POLICY_EXACT_LEN() was not yet available.

[1]
BUG: KMSAN: uninit-value in hash_ip6_add+0x1cba/0x3a50 net/netfilter/ipset/ip_set_hash_gen.h:892
CPU: 1 PID: 11611 Comm: syz-executor.0 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 hash_ip6_add+0x1cba/0x3a50 net/netfilter/ipset/ip_set_hash_gen.h:892
 hash_ip6_uadt+0x976/0xbd0 net/netfilter/ipset/ip_set_hash_ip.c:267
 call_ad+0x329/0xd00 net/netfilter/ipset/ip_set_core.c:1720
 ip_set_ad+0x111f/0x1440 net/netfilter/ipset/ip_set_core.c:1808
 ip_set_uadd+0xf6/0x110 net/netfilter/ipset/ip_set_core.c:1833
 nfnetlink_rcv_msg+0xc7d/0xdf0 net/netfilter/nfnetlink.c:252
 netlink_rcv_skb+0x70a/0x820 net/netlink/af_netlink.c:2494
 nfnetlink_rcv+0x4f0/0x4380 net/netfilter/nfnetlink.c:600
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x11da/0x14b0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x173c/0x1840 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d5/0x830 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45deb9
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe2e503fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000029ec0 RCX: 000000000045deb9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 000000000169fb7f R14: 00007fe2e50409c0 R15: 000000000118bf2c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 __msan_chain_origin+0x57/0xa0 mm/kmsan/kmsan_instr.c:147
 ip6_netmask include/linux/netfilter/ipset/pfxlen.h:49 [inline]
 hash_ip6_netmask net/netfilter/ipset/ip_set_hash_ip.c:185 [inline]
 hash_ip6_uadt+0xb1c/0xbd0 net/netfilter/ipset/ip_set_hash_ip.c:263
 call_ad+0x329/0xd00 net/netfilter/ipset/ip_set_core.c:1720
 ip_set_ad+0x111f/0x1440 net/netfilter/ipset/ip_set_core.c:1808
 ip_set_uadd+0xf6/0x110 net/netfilter/ipset/ip_set_core.c:1833
 nfnetlink_rcv_msg+0xc7d/0xdf0 net/netfilter/nfnetlink.c:252
 netlink_rcv_skb+0x70a/0x820 net/netlink/af_netlink.c:2494
 nfnetlink_rcv+0x4f0/0x4380 net/netfilter/nfnetlink.c:600
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x11da/0x14b0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x173c/0x1840 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d5/0x830 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 kmsan_memcpy_memmove_metadata+0x25e/0x2d0 mm/kmsan/kmsan.c:226
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:246
 __msan_memcpy+0x46/0x60 mm/kmsan/kmsan_instr.c:110
 ip_set_get_ipaddr6+0x2cb/0x370 net/netfilter/ipset/ip_set_core.c:310
 hash_ip6_uadt+0x439/0xbd0 net/netfilter/ipset/ip_set_hash_ip.c:255
 call_ad+0x329/0xd00 net/netfilter/ipset/ip_set_core.c:1720
 ip_set_ad+0x111f/0x1440 net/netfilter/ipset/ip_set_core.c:1808
 ip_set_uadd+0xf6/0x110 net/netfilter/ipset/ip_set_core.c:1833
 nfnetlink_rcv_msg+0xc7d/0xdf0 net/netfilter/nfnetlink.c:252
 netlink_rcv_skb+0x70a/0x820 net/netlink/af_netlink.c:2494
 nfnetlink_rcv+0x4f0/0x4380 net/netfilter/nfnetlink.c:600
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x11da/0x14b0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x173c/0x1840 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d5/0x830 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76
 slab_alloc_node mm/slub.c:2906 [inline]
 __kmalloc_node_track_caller+0xc61/0x15f0 mm/slub.c:4512
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x309/0xae0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1094 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1176 [inline]
 netlink_sendmsg+0xdb8/0x1840 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6d5/0x830 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: a7b4f989a629 ("netfilter: ipset: IP set core support")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/ipset/ip_set_core.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 7cff6e5e7445..2b19189a930f 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -271,8 +271,7 @@ flag_nested(const struct nlattr *nla)
 
 static const struct nla_policy ipaddr_policy[IPSET_ATTR_IPADDR_MAX + 1] = {
 	[IPSET_ATTR_IPADDR_IPV4]	= { .type = NLA_U32 },
-	[IPSET_ATTR_IPADDR_IPV6]	= { .type = NLA_BINARY,
-					    .len = sizeof(struct in6_addr) },
+	[IPSET_ATTR_IPADDR_IPV6]	= NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
 };
 
 int
-- 
2.20.1

[PATCH net 2/5] netfilter: nf_tables: avoid false-postive lockdep splat

[Pablo Neira Ayuso]

From: Florian Westphal <fw@strlen.de>

There are reports wrt lockdep splat in nftables, e.g.:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 31416 at net/netfilter/nf_tables_api.c:622
lockdep_nfnl_nft_mutex_not_held+0x28/0x38 [nf_tables]
...

These are caused by an earlier, unrelated bug such as a n ABBA deadlock
in a different subsystem.
In such an event, lockdep is disabled and lockdep_is_held returns true
unconditionally.  This then causes the WARN() in nf_tables.

Make the WARN conditional on lockdep still active to avoid this.

Fixes: f102d66b335a417 ("netfilter: nf_tables: use dedicated mutex to guard transactions")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Link: https://lore.kernel.org/linux-kselftest/CA+G9fYvFUpODs+NkSYcnwKnXm62tmP=ksLeBPmB+KFrB2rvCtQ@mail.gmail.com/
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_tables_api.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 0f58e98542be..23abf1578594 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -619,7 +619,8 @@ static int nft_request_module(struct net *net, const char *fmt, ...)
 static void lockdep_nfnl_nft_mutex_not_held(void)
 {
 #ifdef CONFIG_PROVE_LOCKING
-	WARN_ON_ONCE(lockdep_nfnl_is_held(NFNL_SUBSYS_NFTABLES));
+	if (debug_locks)
+		WARN_ON_ONCE(lockdep_nfnl_is_held(NFNL_SUBSYS_NFTABLES));
 #endif
 }
 
-- 
2.20.1

[PATCH net 3/5] ipvs: fix possible memory leak in ip_vs_control_net_init

[Pablo Neira Ayuso]

From: Wang Hai <wanghai38@huawei.com>

kmemleak report a memory leak as follows:

BUG: memory leak
unreferenced object 0xffff8880759ea000 (size 256):
backtrace:
[<00000000c0bf2deb>] kmem_cache_zalloc include/linux/slab.h:656 [inline]
[<00000000c0bf2deb>] __proc_create+0x23d/0x7d0 fs/proc/generic.c:421
[<000000009d718d02>] proc_create_reg+0x8e/0x140 fs/proc/generic.c:535
[<0000000097bbfc4f>] proc_create_net_data+0x8c/0x1b0 fs/proc/proc_net.c:126
[<00000000652480fc>] ip_vs_control_net_init+0x308/0x13a0 net/netfilter/ipvs/ip_vs_ctl.c:4169
[<000000004c927ebe>] __ip_vs_init+0x211/0x400 net/netfilter/ipvs/ip_vs_core.c:2429
[<00000000aa6b72d9>] ops_init+0xa8/0x3c0 net/core/net_namespace.c:151
[<00000000153fd114>] setup_net+0x2de/0x7e0 net/core/net_namespace.c:341
[<00000000be4e4f07>] copy_net_ns+0x27d/0x530 net/core/net_namespace.c:482
[<00000000f1c23ec9>] create_new_namespaces+0x382/0xa30 kernel/nsproxy.c:110
[<00000000098a5757>] copy_namespaces+0x2e6/0x3b0 kernel/nsproxy.c:179
[<0000000026ce39e9>] copy_process+0x220a/0x5f00 kernel/fork.c:2072
[<00000000b71f4efe>] _do_fork+0xc7/0xda0 kernel/fork.c:2428
[<000000002974ee96>] __do_sys_clone3+0x18a/0x280 kernel/fork.c:2703
[<0000000062ac0a4d>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
[<0000000093f1ce2c>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

In the error path of ip_vs_control_net_init(), remove_proc_entry() needs
to be called to remove the added proc entry, otherwise a memory leak
will occur.

Also, add some '#ifdef CONFIG_PROC_FS' because proc_create_net* return NULL
when PROC is not used.

Fixes: b17fc9963f83 ("IPVS: netns, ip_vs_stats and its procfs")
Fixes: 61b1ab4583e2 ("IPVS: netns, add basic init per netns.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/ipvs/ip_vs_ctl.c | 31 +++++++++++++++++++++++++------
 1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index e279ded4e306..d45dbcba8b49 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -4167,12 +4167,18 @@ int __net_init ip_vs_control_net_init(struct netns_ipvs *ipvs)
 
 	spin_lock_init(&ipvs->tot_stats.lock);
 
-	proc_create_net("ip_vs", 0, ipvs->net->proc_net, &ip_vs_info_seq_ops,
-			sizeof(struct ip_vs_iter));
-	proc_create_net_single("ip_vs_stats", 0, ipvs->net->proc_net,
-			ip_vs_stats_show, NULL);
-	proc_create_net_single("ip_vs_stats_percpu", 0, ipvs->net->proc_net,
-			ip_vs_stats_percpu_show, NULL);
+#ifdef CONFIG_PROC_FS
+	if (!proc_create_net("ip_vs", 0, ipvs->net->proc_net,
+			     &ip_vs_info_seq_ops, sizeof(struct ip_vs_iter)))
+		goto err_vs;
+	if (!proc_create_net_single("ip_vs_stats", 0, ipvs->net->proc_net,
+				    ip_vs_stats_show, NULL))
+		goto err_stats;
+	if (!proc_create_net_single("ip_vs_stats_percpu", 0,
+				    ipvs->net->proc_net,
+				    ip_vs_stats_percpu_show, NULL))
+		goto err_percpu;
+#endif
 
 	if (ip_vs_control_net_init_sysctl(ipvs))
 		goto err;
@@ -4180,6 +4186,17 @@ int __net_init ip_vs_control_net_init(struct netns_ipvs *ipvs)
 	return 0;
 
 err:
+#ifdef CONFIG_PROC_FS
+	remove_proc_entry("ip_vs_stats_percpu", ipvs->net->proc_net);
+
+err_percpu:
+	remove_proc_entry("ip_vs_stats", ipvs->net->proc_net);
+
+err_stats:
+	remove_proc_entry("ip_vs", ipvs->net->proc_net);
+
+err_vs:
+#endif
 	free_percpu(ipvs->tot_stats.cpustats);
 	return -ENOMEM;
 }
@@ -4188,9 +4205,11 @@ void __net_exit ip_vs_control_net_cleanup(struct netns_ipvs *ipvs)
 {
 	ip_vs_trash_cleanup(ipvs);
 	ip_vs_control_net_cleanup_sysctl(ipvs);
+#ifdef CONFIG_PROC_FS
 	remove_proc_entry("ip_vs_stats_percpu", ipvs->net->proc_net);
 	remove_proc_entry("ip_vs_stats", ipvs->net->proc_net);
 	remove_proc_entry("ip_vs", ipvs->net->proc_net);
+#endif
 	free_percpu(ipvs->tot_stats.cpustats);
 }
 
-- 
2.20.1

[PATCH net 4/5] netfilter: nftables_offload: set address type in control dissector

[Pablo Neira Ayuso]

This patch adds nft_flow_rule_set_addr_type() to set the address type
from the nft_payload expression accordingly.

If the address type is not set in the control dissector then a rule that
matches either on source or destination IP address does not work.

After this patch, nft hardware offload generates the flow dissector
configuration as tc-flower does to match on an IP address.

This patch has been also tested functionally to make sure packets are
filtered out by the NIC.

This is also getting the code aligned with the existing netfilter flow
offload infrastructure which is also setting the control dissector.

Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/net/netfilter/nf_tables_offload.h |  4 ++++
 net/netfilter/nf_tables_offload.c         | 17 +++++++++++++++++
 net/netfilter/nft_payload.c               |  4 ++++
 3 files changed, 25 insertions(+)

diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index ea7d1d78b92d..bddd34c5bd79 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -37,6 +37,7 @@ void nft_offload_update_dependency(struct nft_offload_ctx *ctx,
 
 struct nft_flow_key {
 	struct flow_dissector_key_basic			basic;
+	struct flow_dissector_key_control		control;
 	union {
 		struct flow_dissector_key_ipv4_addrs	ipv4;
 		struct flow_dissector_key_ipv6_addrs	ipv6;
@@ -62,6 +63,9 @@ struct nft_flow_rule {
 
 #define NFT_OFFLOAD_F_ACTION	(1 << 0)
 
+void nft_flow_rule_set_addr_type(struct nft_flow_rule *flow,
+				 enum flow_dissector_key_id addr_type);
+
 struct nft_rule;
 struct nft_flow_rule *nft_flow_rule_create(struct net *net, const struct nft_rule *rule);
 void nft_flow_rule_destroy(struct nft_flow_rule *flow);
diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index 9f625724a20f..9ae14270c543 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -28,6 +28,23 @@ static struct nft_flow_rule *nft_flow_rule_alloc(int num_actions)
 	return flow;
 }
 
+void nft_flow_rule_set_addr_type(struct nft_flow_rule *flow,
+				 enum flow_dissector_key_id addr_type)
+{
+	struct nft_flow_match *match = &flow->match;
+	struct nft_flow_key *mask = &match->mask;
+	struct nft_flow_key *key = &match->key;
+
+	if (match->dissector.used_keys & BIT(FLOW_DISSECTOR_KEY_CONTROL))
+		return;
+
+	key->control.addr_type = addr_type;
+	mask->control.addr_type = 0xffff;
+	match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_CONTROL);
+	match->dissector.offset[FLOW_DISSECTOR_KEY_CONTROL] =
+		offsetof(struct nft_flow_key, control);
+}
+
 struct nft_flow_rule *nft_flow_rule_create(struct net *net,
 					   const struct nft_rule *rule)
 {
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index dcd3c7b8a367..bbf811d030d5 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -244,6 +244,7 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
 				  sizeof(struct in_addr), reg);
+		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 		break;
 	case offsetof(struct iphdr, daddr):
 		if (priv->len != sizeof(struct in_addr))
@@ -251,6 +252,7 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
 				  sizeof(struct in_addr), reg);
+		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 		break;
 	case offsetof(struct iphdr, protocol):
 		if (priv->len != sizeof(__u8))
@@ -280,6 +282,7 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
 				  sizeof(struct in6_addr), reg);
+		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 		break;
 	case offsetof(struct ipv6hdr, daddr):
 		if (priv->len != sizeof(struct in6_addr))
@@ -287,6 +290,7 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
 				  sizeof(struct in6_addr), reg);
+		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 		break;
 	case offsetof(struct ipv6hdr, nexthdr):
 		if (priv->len != sizeof(__u8))
-- 
2.20.1

[PATCH net 5/5] netfilter: nftables_offload: build mask based from the matching bytes

[Pablo Neira Ayuso]

Userspace might match on prefix bytes of header fields if they are on
the byte boundary, this requires that the mask is adjusted accordingly.
Use NFT_OFFLOAD_MATCH_EXACT() for meta since prefix byte matching is not
allowed for this type of selector.

The bitwise expression might be optimized out by userspace, hence the
kernel needs to infer the prefix from the number of payload bytes to
match on. This patch adds nft_payload_offload_mask() to calculate the
bitmask to match on the prefix.

Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/net/netfilter/nf_tables_offload.h |  3 ++
 net/netfilter/nft_cmp.c                   |  8 +--
 net/netfilter/nft_meta.c                  | 16 +++---
 net/netfilter/nft_payload.c               | 66 +++++++++++++++++------
 4 files changed, 64 insertions(+), 29 deletions(-)

diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index bddd34c5bd79..1d34fe154fe0 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -78,6 +78,9 @@ int nft_flow_rule_offload_commit(struct net *net);
 		offsetof(struct nft_flow_key, __base.__field);		\
 	(__reg)->len		= __len;				\
 	(__reg)->key		= __key;				\
+
+#define NFT_OFFLOAD_MATCH_EXACT(__key, __base, __field, __len, __reg)	\
+	NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg)		\
 	memset(&(__reg)->mask, 0xff, (__reg)->len);
 
 int nft_chain_offload_priority(struct nft_base_chain *basechain);
diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c
index bc079d68a536..00e563a72d3d 100644
--- a/net/netfilter/nft_cmp.c
+++ b/net/netfilter/nft_cmp.c
@@ -123,11 +123,11 @@ static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
 	u8 *mask = (u8 *)&flow->match.mask;
 	u8 *key = (u8 *)&flow->match.key;
 
-	if (priv->op != NFT_CMP_EQ || reg->len != priv->len)
+	if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
 		return -EOPNOTSUPP;
 
-	memcpy(key + reg->offset, &priv->data, priv->len);
-	memcpy(mask + reg->offset, &reg->mask, priv->len);
+	memcpy(key + reg->offset, &priv->data, reg->len);
+	memcpy(mask + reg->offset, &reg->mask, reg->len);
 
 	flow->match.dissector.used_keys |= BIT(reg->key);
 	flow->match.dissector.offset[reg->key] = reg->base_offset;
@@ -137,7 +137,7 @@ static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
 	    nft_reg_load16(priv->data.data) != ARPHRD_ETHER)
 		return -EOPNOTSUPP;
 
-	nft_offload_update_dependency(ctx, &priv->data, priv->len);
+	nft_offload_update_dependency(ctx, &priv->data, reg->len);
 
 	return 0;
 }
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index b37bd02448d8..bf4b3ad5314c 100644
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -724,22 +724,22 @@ static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
 
 	switch (priv->key) {
 	case NFT_META_PROTOCOL:
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
-				  sizeof(__u16), reg);
+		NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
+					sizeof(__u16), reg);
 		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 		break;
 	case NFT_META_L4PROTO:
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
-				  sizeof(__u8), reg);
+		NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
+					sizeof(__u8), reg);
 		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
 		break;
 	case NFT_META_IIF:
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_META, meta,
-				  ingress_ifindex, sizeof(__u32), reg);
+		NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
+					ingress_ifindex, sizeof(__u32), reg);
 		break;
 	case NFT_META_IIFTYPE:
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_META, meta,
-				  ingress_iftype, sizeof(__u16), reg);
+		NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
+					ingress_iftype, sizeof(__u16), reg);
 		break;
 	default:
 		return -EOPNOTSUPP;
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index bbf811d030d5..47d4e0e21651 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -165,6 +165,34 @@ static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
 	return -1;
 }
 
+static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
+				     u32 priv_len, u32 field_len)
+{
+	unsigned int remainder, delta, k;
+	struct nft_data mask = {};
+	__be32 remainder_mask;
+
+	if (priv_len == field_len) {
+		memset(&reg->mask, 0xff, priv_len);
+		return true;
+	} else if (priv_len > field_len) {
+		return false;
+	}
+
+	memset(&mask, 0xff, field_len);
+	remainder = priv_len % sizeof(u32);
+	if (remainder) {
+		k = priv_len / sizeof(u32);
+		delta = field_len - priv_len;
+		remainder_mask = htonl(~((1 << (delta * BITS_PER_BYTE)) - 1));
+		mask.data[k] = (__force u32)remainder_mask;
+	}
+
+	memcpy(&reg->mask, &mask, field_len);
+
+	return true;
+}
+
 static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 				  struct nft_flow_rule *flow,
 				  const struct nft_payload *priv)
@@ -173,21 +201,21 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 
 	switch (priv->offset) {
 	case offsetof(struct ethhdr, h_source):
-		if (priv->len != ETH_ALEN)
+		if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
 				  src, ETH_ALEN, reg);
 		break;
 	case offsetof(struct ethhdr, h_dest):
-		if (priv->len != ETH_ALEN)
+		if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
 				  dst, ETH_ALEN, reg);
 		break;
 	case offsetof(struct ethhdr, h_proto):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic,
@@ -195,14 +223,14 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_TCI):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
 				  vlan_tci, sizeof(__be16), reg);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
@@ -210,7 +238,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_TCI) + sizeof(struct vlan_hdr):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
@@ -218,7 +246,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
 							sizeof(struct vlan_hdr):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
@@ -239,7 +267,8 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 
 	switch (priv->offset) {
 	case offsetof(struct iphdr, saddr):
-		if (priv->len != sizeof(struct in_addr))
+		if (!nft_payload_offload_mask(reg, priv->len,
+					      sizeof(struct in_addr)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
@@ -247,7 +276,8 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 		break;
 	case offsetof(struct iphdr, daddr):
-		if (priv->len != sizeof(struct in_addr))
+		if (!nft_payload_offload_mask(reg, priv->len,
+					      sizeof(struct in_addr)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
@@ -255,7 +285,7 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 		break;
 	case offsetof(struct iphdr, protocol):
-		if (priv->len != sizeof(__u8))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
@@ -277,7 +307,8 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 
 	switch (priv->offset) {
 	case offsetof(struct ipv6hdr, saddr):
-		if (priv->len != sizeof(struct in6_addr))
+		if (!nft_payload_offload_mask(reg, priv->len,
+					      sizeof(struct in6_addr)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
@@ -285,7 +316,8 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 		break;
 	case offsetof(struct ipv6hdr, daddr):
-		if (priv->len != sizeof(struct in6_addr))
+		if (!nft_payload_offload_mask(reg, priv->len,
+					      sizeof(struct in6_addr)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
@@ -293,7 +325,7 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 		break;
 	case offsetof(struct ipv6hdr, nexthdr):
-		if (priv->len != sizeof(__u8))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
@@ -335,14 +367,14 @@ static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx,
 
 	switch (priv->offset) {
 	case offsetof(struct tcphdr, source):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
 				  sizeof(__be16), reg);
 		break;
 	case offsetof(struct tcphdr, dest):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
@@ -363,14 +395,14 @@ static int nft_payload_offload_udp(struct nft_offload_ctx *ctx,
 
 	switch (priv->offset) {
 	case offsetof(struct udphdr, source):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
 				  sizeof(__be16), reg);
 		break;
 	case offsetof(struct udphdr, dest):
-		if (priv->len != sizeof(__be16))
+		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
 		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
-- 
2.20.1

Re: [PATCH net 0/5] Netfilter fixes for net

[Jakub Kicinski]

On Fri, 27 Nov 2020 20:03:08 +0100 Pablo Neira Ayuso wrote:
> 1) Fix insufficient validation of IPSET_ATTR_IPADDR_IPV6 reported
>    by syzbot.
> 
> 2) Remove spurious reports on nf_tables when lockdep gets disabled,
>    from Florian Westphal.
> 
> 3) Fix memleak in the error path of error path of
>    ip_vs_control_net_init(), from Wang Hai.
> 
> 4) Fix missing control data in flow dissector, otherwise IP address
>    matching in hardware offload infra does not work.
> 
> 5) Fix hardware offload match on prefix IP address when userspace
>    does not send a bitwise expression to represent the prefix.
> 
> Please, pull these changes from:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git

Pulled, thanks!