Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains three Netfilter updates, they are:

* Fix wrong usage of skb_header_pointer in the DCCP protocol helper that
  has been there for quite some time. It was resulting in copying the dccp
  header to a pointer allocated in the stack. Fortunately, this pointer
  provides room for the dccp header is 4 bytes long, so no crashes have been
  reported so far. From Daniel Borkmann.

* Use format string to print in the invocation of nf_log_packet(), again
  in the DCCP helper. Also from Daniel Borkmann.

* Revert "netfilter: avoid get_random_bytes call" as prandom32 does not
  guarantee enough entropy when being calling this at boot time, that may
  happen when reloading the rule.
====================

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

7 files changed, 18 insertions, 10 deletions

diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c
index a99b6c3427b0..cb372f96f10d 100644
--- a/net/netfilter/nf_conntrack_proto_dccp.c
+++ b/net/netfilter/nf_conntrack_proto_dccp.c
@@ -428,7 +428,7 @@ static bool dccp_new(struct nf_conn *ct, const struct sk_buff *skb,
         const char *msg;
         u_int8_t state;
 
-        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
+        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
         BUG_ON(dh == NULL);
 
         state = dccp_state_table[CT_DCCP_ROLE_CLIENT][dh->dccph_type][CT_DCCP_NONE];
@@ -457,7 +457,7 @@ static bool dccp_new(struct nf_conn *ct, const struct sk_buff *skb,
 out_invalid:
         if (LOG_INVALID(net, IPPROTO_DCCP))
                 nf_log_packet(net, nf_ct_l3num(ct), 0, skb, NULL, NULL,
-                              NULL, msg);
+                              NULL, "%s", msg);
         return false;
 }
 
@@ -486,7 +486,7 @@ static int dccp_packet(struct nf_conn *ct, const struct sk_buff *skb,
         u_int8_t type, old_state, new_state;
         enum ct_dccp_roles role;
 
-        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
+        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
         BUG_ON(dh == NULL);
         type = dh->dccph_type;
 
@@ -577,7 +577,7 @@ static int dccp_error(struct net *net, struct nf_conn *tmpl,
         unsigned int cscov;
         const char *msg;
 
-        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
+        dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
         if (dh == NULL) {
                 msg = "nf_ct_dccp: short packet ";
                 goto out_invalid;
@@ -614,7 +614,7 @@ static int dccp_error(struct net *net, struct nf_conn *tmpl,
 
 out_invalid:
         if (LOG_INVALID(net, IPPROTO_DCCP))
-                nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, msg);
+                nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, "%s", msg);
         return -NF_ACCEPT;
 }
 
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index d292c8d286eb..a155d19a225e 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -28,6 +28,8 @@
 #include <linux/proc_fs.h>
 #include <linux/security.h>
 #include <linux/list.h>
+#include <linux/jhash.h>
+#include <linux/random.h>
 #include <linux/slab.h>
 #include <net/sock.h>
 #include <net/netfilter/nf_log.h>
@@ -73,6 +75,7 @@ struct nfulnl_instance {
 };
 
 #define INSTANCE_BUCKETS        16
+static unsigned int hash_init;
 
 static int nfnl_log_net_id __read_mostly;
 
@@ -1064,6 +1067,11 @@ static int __init nfnetlink_log_init(void)
 {
         int status = -ENOMEM;
 
+        /* it's not really all that important to have a random value, so
+         * we can do this from the init function, even if there hasn't
+         * been that much entropy yet */
+        get_random_bytes(&hash_init, sizeof(hash_init));
+
         netlink_register_notifier(&nfulnl_rtnl_notifier);
         status = nfnetlink_subsys_register(&nfulnl_subsys);
         if (status < 0) {
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index 6aae699aeb46..3d3f8fce10a5 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -164,7 +164,7 @@ static int nft_hash_init(const struct nft_set *set,
         unsigned int cnt, i;
 
         if (unlikely(!nft_hash_rnd_initted)) {
-                nft_hash_rnd = prandom_u32();
+                get_random_bytes(&nft_hash_rnd, 4);
                 nft_hash_rnd_initted = true;
         }
 
diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c
index 190854be7629..370adf622cef 100644
--- a/net/netfilter/xt_RATEEST.c
+++ b/net/netfilter/xt_RATEEST.c
@@ -100,7 +100,7 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
         int ret;
 
         if (unlikely(!rnd_inited)) {
-                jhash_rnd = prandom_u32();
+                get_random_bytes(&jhash_rnd, sizeof(jhash_rnd));
                 rnd_inited = true;
         }
 
diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c
index 7671e8214919..c40b2695633b 100644
--- a/net/netfilter/xt_connlimit.c
+++ b/net/netfilter/xt_connlimit.c
@@ -229,7 +229,7 @@ static int connlimit_mt_check(const struct xt_mtchk_param *par)
                 u_int32_t rand;
 
                 do {
-                        rand = prandom_u32();
+                        get_random_bytes(&rand, sizeof(rand));
                 } while (!rand);
                 cmpxchg(&connlimit_rnd, 0, rand);
         }
diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c
index d819f62b3b7c..a3910fc2122b 100644
--- a/net/netfilter/xt_hashlimit.c
+++ b/net/netfilter/xt_hashlimit.c
@@ -177,7 +177,7 @@ dsthash_alloc_init(struct xt_hashlimit_htable *ht,
         /* initialize hash with random val at the time we allocate
          * the first hashtable entry */
         if (unlikely(!ht->rnd_initialized)) {
-                ht->rnd = prandom_u32();
+                get_random_bytes(&ht->rnd, sizeof(ht->rnd));
                 ht->rnd_initialized = true;
         }
 
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index bfdc29f1a04a..1e657cf715c4 100644
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -334,7 +334,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
         size_t sz;
 
         if (unlikely(!hash_rnd_inited)) {
-                hash_rnd = prandom_u32();
+                get_random_bytes(&hash_rnd, sizeof(hash_rnd));
                 hash_rnd_inited = true;
         }
         if (info->check_set & ~XT_RECENT_VALID_FLAGS) {