1 files changed, 81 insertions, 43 deletions

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index c9423763107..a9adf4c6b29 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -23,6 +23,7 @@
 #include <linux/mutex.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
+#include <linux/audit.h>
 #include <net/net_namespace.h>
 
 #include <linux/netfilter/x_tables.h>
@@ -38,9 +39,8 @@ MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
 
 struct compat_delta {
-        struct compat_delta *next;
-        unsigned int offset;
-        int delta;
+        unsigned int offset; /* offset in kernel */
+        int delta; /* delta in 32bit user land */
 };
 
 struct xt_af {
@@ -49,7 +49,9 @@ struct xt_af {
         struct list_head target;
 #ifdef CONFIG_COMPAT
         struct mutex compat_mutex;
-        struct compat_delta *compat_offsets;
+        struct compat_delta *compat_tab;
+        unsigned int number; /* number of slots in compat_tab[] */
+        unsigned int cur; /* number of used slots in compat_tab[] */
 #endif
 };
 
@@ -181,14 +183,14 @@ EXPORT_SYMBOL(xt_unregister_matches);
 /*
  * These are weird, but module loading must not be done with mutex
  * held (since they will register), and we have to have a single
- * function to use try_then_request_module().
+ * function to use.
  */
 
 /* Find match, grabs ref.  Returns ERR_PTR() on error. */
 struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
 {
         struct xt_match *m;
-        int err = 0;
+        int err = -ENOENT;
 
         if (mutex_lock_interruptible(&xt[af].mutex) != 0)
                 return ERR_PTR(-EINTR);
@@ -219,9 +221,13 @@ xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
 {
         struct xt_match *match;
 
-        match = try_then_request_module(xt_find_match(nfproto, name, revision),
-                                        "%st_%s", xt_prefix[nfproto], name);
-        return (match != NULL) ? match : ERR_PTR(-ENOENT);
+        match = xt_find_match(nfproto, name, revision);
+        if (IS_ERR(match)) {
+                request_module("%st_%s", xt_prefix[nfproto], name);
+                match = xt_find_match(nfproto, name, revision);
+        }
+
+        return match;
 }
 EXPORT_SYMBOL_GPL(xt_request_find_match);
 
@@ -229,7 +235,7 @@ EXPORT_SYMBOL_GPL(xt_request_find_match);
 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
 {
         struct xt_target *t;
-        int err = 0;
+        int err = -ENOENT;
 
         if (mutex_lock_interruptible(&xt[af].mutex) != 0)
                 return ERR_PTR(-EINTR);
@@ -259,9 +265,13 @@ struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
 {
         struct xt_target *target;
 
-        target = try_then_request_module(xt_find_target(af, name, revision),
-                                         "%st_%s", xt_prefix[af], name);
-        return (target != NULL) ? target : ERR_PTR(-ENOENT);
+        target = xt_find_target(af, name, revision);
+        if (IS_ERR(target)) {
+                request_module("%st_%s", xt_prefix[af], name);
+                target = xt_find_target(af, name, revision);
+        }
+
+        return target;
 }
 EXPORT_SYMBOL_GPL(xt_request_find_target);
 
@@ -414,54 +424,67 @@ int xt_check_match(struct xt_mtchk_param *par,
 EXPORT_SYMBOL_GPL(xt_check_match);
 
 #ifdef CONFIG_COMPAT
-int xt_compat_add_offset(u_int8_t af, unsigned int offset, short delta)
+int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
 {
-        struct compat_delta *tmp;
+        struct xt_af *xp = &xt[af];
 
-        tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
-        if (!tmp)
-                return -ENOMEM;
+        if (!xp->compat_tab) {
+                if (!xp->number)
+                        return -EINVAL;
+                xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
+                if (!xp->compat_tab)
+                        return -ENOMEM;
+                xp->cur = 0;
+        }
 
-        tmp->offset = offset;
-        tmp->delta = delta;
+        if (xp->cur >= xp->number)
+                return -EINVAL;
 
-        if (xt[af].compat_offsets) {
-                tmp->next = xt[af].compat_offsets->next;
-                xt[af].compat_offsets->next = tmp;
-        } else {
-                xt[af].compat_offsets = tmp;
-                tmp->next = NULL;
-        }
+        if (xp->cur)
+                delta += xp->compat_tab[xp->cur - 1].delta;
+        xp->compat_tab[xp->cur].offset = offset;
+        xp->compat_tab[xp->cur].delta = delta;
+        xp->cur++;
         return 0;
 }
 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
 
 void xt_compat_flush_offsets(u_int8_t af)
 {
-        struct compat_delta *tmp, *next;
-
-        if (xt[af].compat_offsets) {
-                for (tmp = xt[af].compat_offsets; tmp; tmp = next) {
-                        next = tmp->next;
-                        kfree(tmp);
-                }
-                xt[af].compat_offsets = NULL;
+        if (xt[af].compat_tab) {
+                vfree(xt[af].compat_tab);
+                xt[af].compat_tab = NULL;
+                xt[af].number = 0;
         }
 }
 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
 
 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
 {
-        struct compat_delta *tmp;
-        int delta;
-
-        for (tmp = xt[af].compat_offsets, delta = 0; tmp; tmp = tmp->next)
-                if (tmp->offset < offset)
-                        delta += tmp->delta;
-        return delta;
+        struct compat_delta *tmp = xt[af].compat_tab;
+        int mid, left = 0, right = xt[af].cur - 1;
+
+        while (left <= right) {
+                mid = (left + right) >> 1;
+                if (offset > tmp[mid].offset)
+                        left = mid + 1;
+                else if (offset < tmp[mid].offset)
+                        right = mid - 1;
+                else
+                        return mid ? tmp[mid - 1].delta : 0;
+        }
+        WARN_ON_ONCE(1);
+        return 0;
 }
 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
 
+void xt_compat_init_offsets(u_int8_t af, unsigned int number)
+{
+        xt[af].number = number;
+        xt[af].cur = 0;
+}
+EXPORT_SYMBOL(xt_compat_init_offsets);
+
 int xt_compat_match_offset(const struct xt_match *match)
 {
         u_int16_t csize = match->compatsize ? : match->matchsize;
@@ -820,6 +843,21 @@ xt_replace_table(struct xt_table *table,
          */
         local_bh_enable();
 
+#ifdef CONFIG_AUDIT
+        if (audit_enabled) {
+                struct audit_buffer *ab;
+
+                ab = audit_log_start(current->audit_context, GFP_KERNEL,
+                                     AUDIT_NETFILTER_CFG);
+                if (ab) {
+                        audit_log_format(ab, "table=%s family=%u entries=%u",
+                                         table->name, table->af,
+                                         private->number);
+                        audit_log_end(ab);
+                }
+        }
+#endif
+
         return private;
 }
 EXPORT_SYMBOL_GPL(xt_replace_table);
@@ -1338,7 +1376,7 @@ static int __init xt_init(void)
                 mutex_init(&xt[i].mutex);
 #ifdef CONFIG_COMPAT
                 mutex_init(&xt[i].compat_mutex);
-                xt[i].compat_offsets = NULL;
+                xt[i].compat_tab = NULL;
 #endif
                 INIT_LIST_HEAD(&xt[i].target);
                 INIT_LIST_HEAD(&xt[i].match);