netfilter: xtables: avoid pointer to self

Commit 784544739a25c30637397ace5489eeb6e15d7d49 (netfilter: iptables:
lock free counters) broke a number of modules whose rule data referenced
itself. A reallocation would not reestablish the correct references, so
it is best to use a separate struct that does not fall under RCU.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

3 files changed, 12 insertions, 8 deletions

diff --git a/include/linux/netfilter/xt_limit.h b/include/linux/netfilter/xt_limit.h
index b3ce65375ecb..fda222c7953b 100644
--- a/include/linux/netfilter/xt_limit.h
+++ b/include/linux/netfilter/xt_limit.h
@@ -4,6 +4,8 @@
 /* timings are in milliseconds. */
 #define XT_LIMIT_SCALE 10000
 
+struct xt_limit_priv;
+
 /* 1/10,000 sec period => max of 10,000/sec.  Min rate is then 429490
    seconds, or one every 59 hours. */
 struct xt_rateinfo {
@@ -11,11 +13,10 @@ struct xt_rateinfo {
         u_int32_t burst;  /* Period multiplier for upper limit. */
 
         /* Used internally by the kernel */
-        unsigned long prev;
-        u_int32_t credit;
+        unsigned long prev; /* moved to xt_limit_priv */
+        u_int32_t credit; /* moved to xt_limit_priv */
         u_int32_t credit_cap, cost;
 
-        /* Ugly, ugly fucker. */
-        struct xt_rateinfo *master;
+        struct xt_limit_priv *master;
 };
 #endif /*_XT_RATE_H*/
diff --git a/include/linux/netfilter/xt_quota.h b/include/linux/netfilter/xt_quota.h
index 4c8368d781e5..8dc89dfc1361 100644
--- a/include/linux/netfilter/xt_quota.h
+++ b/include/linux/netfilter/xt_quota.h
@@ -6,13 +6,15 @@ enum xt_quota_flags {
 };
 #define XT_QUOTA_MASK           0x1
 
+struct xt_quota_priv;
+
 struct xt_quota_info {
         u_int32_t               flags;
         u_int32_t               pad;
 
         /* Used internally by the kernel */
         aligned_u64             quota;
-        struct xt_quota_info    *master;
+        struct xt_quota_priv    *master;
 };
 
 #endif /* _XT_QUOTA_H */
diff --git a/include/linux/netfilter/xt_statistic.h b/include/linux/netfilter/xt_statistic.h
index 3d38bc975048..8f521ab49ef7 100644
--- a/include/linux/netfilter/xt_statistic.h
+++ b/include/linux/netfilter/xt_statistic.h
@@ -13,6 +13,8 @@ enum xt_statistic_flags {
 };
 #define XT_STATISTIC_MASK               0x1
 
+struct xt_statistic_priv;
+
 struct xt_statistic_info {
         u_int16_t                       mode;
         u_int16_t                       flags;
@@ -23,11 +25,10 @@ struct xt_statistic_info {
                 struct {
                         u_int32_t       every;
                         u_int32_t       packet;
-                        /* Used internally by the kernel */
-                        u_int32_t       count;
+                        u_int32_t       count; /* unused */
                 } nth;
         } u;
-        struct xt_statistic_info        *master __attribute__((aligned(8)));
+        struct xt_statistic_priv *master __attribute__((aligned(8)));
 };
 
 #endif /* _XT_STATISTIC_H */