netfilter: ebtables: only call xt_compat_add_offset once per rule

The optimizations in commit 255d0dc34068a976
(netfilter: x_table: speedup compat operations) assume that
xt_compat_add_offset is called once per rule.

ebtables however called it for each match/target found in a rule.

The match/watcher/target parser already returns the needed delta, so it
is sufficient to move the xt_compat_add_offset call to a more reasonable
location.

While at it, also get rid of the unused COMPAT iterator macros.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 9707079bc40a82d196cc9eb48d6b97da9dd5326e..1a92b369c8202c8706c42452950594233882ca06 100644 (file)
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1882,7 +1882,7 @@ static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
        struct xt_match *match;
        struct xt_target *wt;
        void *dst = NULL;
-       int off, pad = 0, ret = 0;
+       int off, pad = 0;
        unsigned int size_kern, entry_offset, match_size = mwt->match_size;
 
        strlcpy(name, mwt->u.name, sizeof(name));
@@ -1935,13 +1935,6 @@ static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
                break;
        }
 
-       if (!dst) {
-               ret = xt_compat_add_offset(NFPROTO_BRIDGE, entry_offset,
-                                       off + ebt_compat_entry_padsize());
-               if (ret < 0)
-                       return ret;
-       }
-
        state->buf_kern_offset += match_size + off;
        state->buf_user_offset += match_size;
        pad = XT_ALIGN(size_kern) - size_kern;
@@ -2016,50 +2009,6 @@ static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32,
        return growth;
 }
 
-#define EBT_COMPAT_WATCHER_ITERATE(e, fn, args...)          \
-({                                                          \
-       unsigned int __i;                                   \
-       int __ret = 0;                                      \
-       struct compat_ebt_entry_mwt *__watcher;             \
-                                                           \
-       for (__i = e->watchers_offset;                      \
-            __i < (e)->target_offset;                      \
-            __i += __watcher->watcher_size +               \
-            sizeof(struct compat_ebt_entry_mwt)) {         \
-               __watcher = (void *)(e) + __i;              \
-               __ret = fn(__watcher , ## args);            \
-               if (__ret != 0)                             \
-                       break;                              \
-       }                                                   \
-       if (__ret == 0) {                                   \
-               if (__i != (e)->target_offset)              \
-                       __ret = -EINVAL;                    \
-       }                                                   \
-       __ret;                                              \
-})
-
-#define EBT_COMPAT_MATCH_ITERATE(e, fn, args...)            \
-({                                                          \
-       unsigned int __i;                                   \
-       int __ret = 0;                                      \
-       struct compat_ebt_entry_mwt *__match;               \
-                                                           \
-       for (__i = sizeof(struct ebt_entry);                \
-            __i < (e)->watchers_offset;                    \
-            __i += __match->match_size +                   \
-            sizeof(struct compat_ebt_entry_mwt)) {         \
-               __match = (void *)(e) + __i;                \
-               __ret = fn(__match , ## args);              \
-               if (__ret != 0)                             \
-                       break;                              \
-       }                                                   \
-       if (__ret == 0) {                                   \
-               if (__i != (e)->watchers_offset)            \
-                       __ret = -EINVAL;                    \
-       }                                                   \
-       __ret;                                              \
-})
-
 /* called for all ebt_entry structures. */
 static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base,
                          unsigned int *total,
@@ -2132,6 +2081,14 @@ static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base,
                }
        }
 
+       if (state->buf_kern_start == NULL) {
+               unsigned int offset = buf_start - (char *) base;
+
+               ret = xt_compat_add_offset(NFPROTO_BRIDGE, offset, new_offset);
+               if (ret < 0)
+                       return ret;
+       }
+
        startoff = state->buf_user_offset - startoff;
 
        BUG_ON(*total < startoff);