[PATCH AUTOSEL 4.4 2/8] netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net

[PATCH AUTOSEL 4.4 2/8] netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net

[Sasha Levin]

From: Eric Westbrook <eric@westbrook.io>

[ Upstream commit 886503f34d63e681662057448819edb5b1057a97 ]

Allow /0 as advertised for hash:net,port,net sets.

For "hash:net,port,net", ipset(8) says that "either subnet
is permitted to be a /0 should you wish to match port
between all destinations."

Make that statement true.

Before:

    # ipset create cidrzero hash:net,port,net
    # ipset add cidrzero 0.0.0.0/0,12345,0.0.0.0/0
    ipset v6.34: The value of the CIDR parameter of the IP address is invalid

    # ipset create cidrzero6 hash:net,port,net family inet6
    # ipset add cidrzero6 ::/0,12345,::/0
    ipset v6.34: The value of the CIDR parameter of the IP address is invalid

After:

    # ipset create cidrzero hash:net,port,net
    # ipset add cidrzero 0.0.0.0/0,12345,0.0.0.0/0
    # ipset test cidrzero 192.168.205.129,12345,172.16.205.129
    192.168.205.129,tcp:12345,172.16.205.129 is in set cidrzero.

    # ipset create cidrzero6 hash:net,port,net family inet6
    # ipset add cidrzero6 ::/0,12345,::/0
    # ipset test cidrzero6 fe80::1,12345,ff00::1
    fe80::1,tcp:12345,ff00::1 is in set cidrzero6.

See also:

  https://bugzilla.kernel.org/show_bug.cgi?id=200897
  https://github.com/ewestbrook/linux/commit/df7ff6efb0934ab6acc11f003ff1a7580d6c1d9c

Signed-off-by: Eric Westbrook <linux@westbrook.io>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/ipset/ip_set_hash_netportnet.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_hash_netportnet.c b/net/netfilter/ipset/ip_set_hash_netportnet.c
index 9a14c237830f..b259a5814965 100644
--- a/net/netfilter/ipset/ip_set_hash_netportnet.c
+++ b/net/netfilter/ipset/ip_set_hash_netportnet.c
@@ -213,13 +213,13 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	if (tb[IPSET_ATTR_CIDR]) {
 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
-		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+		if (e.cidr[0] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
 	if (tb[IPSET_ATTR_CIDR2]) {
 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+		if (e.cidr[1] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
@@ -492,13 +492,13 @@ hash_netportnet6_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	if (tb[IPSET_ATTR_CIDR]) {
 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
-		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+		if (e.cidr[0] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
 	if (tb[IPSET_ATTR_CIDR2]) {
 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+		if (e.cidr[1] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
 	}
 
-- 
2.17.1

[PATCH AUTOSEL 4.4 4/8] netfilter: ipset: Correct rcu_dereference() call in ip_set_put_comment()

[Sasha Levin]

From: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>

[ Upstream commit 17b8b74c0f8dbf9b9e3301f9ca5b65dd1c079951 ]

The function is called when rcu_read_lock() is held and not
when rcu_read_lock_bh() is held.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/netfilter/ipset/ip_set_comment.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/netfilter/ipset/ip_set_comment.h b/include/linux/netfilter/ipset/ip_set_comment.h
index 8d0248525957..9f34204978e4 100644
--- a/include/linux/netfilter/ipset/ip_set_comment.h
+++ b/include/linux/netfilter/ipset/ip_set_comment.h
@@ -41,11 +41,11 @@ ip_set_init_comment(struct ip_set_comment *comment,
 	rcu_assign_pointer(comment->c, c);
 }
 
-/* Used only when dumping a set, protected by rcu_read_lock_bh() */
+/* Used only when dumping a set, protected by rcu_read_lock() */
 static inline int
 ip_set_put_comment(struct sk_buff *skb, struct ip_set_comment *comment)
 {
-	struct ip_set_comment_rcu *c = rcu_dereference_bh(comment->c);
+	struct ip_set_comment_rcu *c = rcu_dereference(comment->c);
 
 	if (!c)
 		return 0;
-- 
2.17.1

[PATCH AUTOSEL 4.4 5/8] netfilter: xt_IDLETIMER: add sysfs filename checking routine

[Sasha Levin]

From: Taehee Yoo <ap420073@gmail.com>

[ Upstream commit 54451f60c8fa061af9051a53be9786393947367c ]

When IDLETIMER rule is added, sysfs file is created under
/sys/class/xt_idletimer/timers/
But some label name shouldn't be used.
".", "..", "power", "uevent", "subsystem", etc...
So that sysfs filename checking routine is needed.

test commands:
   %iptables -I INPUT -j IDLETIMER --timeout 1 --label "power"

splat looks like:
[95765.423132] sysfs: cannot create duplicate filename '/devices/virtual/xt_idletimer/timers/power'
[95765.433418] CPU: 0 PID: 8446 Comm: iptables Not tainted 4.19.0-rc6+ #20
[95765.449755] Call Trace:
[95765.449755]  dump_stack+0xc9/0x16b
[95765.449755]  ? show_regs_print_info+0x5/0x5
[95765.449755]  sysfs_warn_dup+0x74/0x90
[95765.449755]  sysfs_add_file_mode_ns+0x352/0x500
[95765.449755]  sysfs_create_file_ns+0x179/0x270
[95765.449755]  ? sysfs_add_file_mode_ns+0x500/0x500
[95765.449755]  ? idletimer_tg_checkentry+0x3e5/0xb1b [xt_IDLETIMER]
[95765.449755]  ? rcu_read_lock_sched_held+0x114/0x130
[95765.449755]  ? __kmalloc_track_caller+0x211/0x2b0
[95765.449755]  ? memcpy+0x34/0x50
[95765.449755]  idletimer_tg_checkentry+0x4e2/0xb1b [xt_IDLETIMER]
[ ... ]

Fixes: 0902b469bd25 ("netfilter: xtables: idletimer target implementation")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/netfilter/xt_IDLETIMER.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c
index 1718f536689f..8a1d2af3eed0 100644
--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -116,6 +116,22 @@ static void idletimer_tg_expired(unsigned long data)
 	schedule_work(&timer->work);
 }
 
+static int idletimer_check_sysfs_name(const char *name, unsigned int size)
+{
+	int ret;
+
+	ret = xt_check_proc_name(name, size);
+	if (ret < 0)
+		return ret;
+
+	if (!strcmp(name, "power") ||
+	    !strcmp(name, "subsystem") ||
+	    !strcmp(name, "uevent"))
+		return -EINVAL;
+
+	return 0;
+}
+
 static int idletimer_tg_create(struct idletimer_tg_info *info)
 {
 	int ret;
@@ -126,6 +142,10 @@ static int idletimer_tg_create(struct idletimer_tg_info *info)
 		goto out;
 	}
 
+	ret = idletimer_check_sysfs_name(info->label, sizeof(info->label));
+	if (ret < 0)
+		goto out_free_timer;
+
 	sysfs_attr_init(&info->timer->attr.attr);
 	info->timer->attr.attr.name = kstrdup(info->label, GFP_KERNEL);
 	if (!info->timer->attr.attr.name) {
-- 
2.17.1