netfilter: ebtables: Use vmalloc_array() to improve code

Remove array_size() calls and replace vmalloc() with vmalloc_array() to
simplify the code.  vmalloc_array() is also optimized better, uses fewer
instructions, and handles overflow more concisely[1].

[1]: https://lore.kernel.org/lkml/abc66ec5-85a4-47e1-9759-2f60ab111971@vivo.com/
Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 3e67d4aff419b9d3fddd5b8a1f8f6b82a00eaaf2..5697e3949a36529b6803d14a3aac67ada9db84d6 100644 (file)
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -920,8 +920,8 @@ static int translate_table(struct net *net, const char *name,
                 * if an error occurs
                 */
                newinfo->chainstack =
-                       vmalloc(array_size(nr_cpu_ids,
-                                          sizeof(*(newinfo->chainstack))));
+                       vmalloc_array(nr_cpu_ids,
+                                     sizeof(*(newinfo->chainstack)));
                if (!newinfo->chainstack)
                        return -ENOMEM;
                for_each_possible_cpu(i) {
@@ -938,7 +938,7 @@ static int translate_table(struct net *net, const char *name,
                        }
                }
 
-               cl_s = vmalloc(array_size(udc_cnt, sizeof(*cl_s)));
+               cl_s = vmalloc_array(udc_cnt, sizeof(*cl_s));
                if (!cl_s)
                        return -ENOMEM;
                i = 0; /* the i'th udc */
@@ -1018,8 +1018,8 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl,
         * the check on the size is done later, when we have the lock
         */
        if (repl->num_counters) {
-               unsigned long size = repl->num_counters * sizeof(*counterstmp);
-               counterstmp = vmalloc(size);
+               counterstmp = vmalloc_array(repl->num_counters,
+                                           sizeof(*counterstmp));
                if (!counterstmp)
                        return -ENOMEM;
        }
@@ -1386,7 +1386,7 @@ static int do_update_counters(struct net *net, const char *name,
        if (num_counters == 0)
                return -EINVAL;
 
-       tmp = vmalloc(array_size(num_counters, sizeof(*tmp)));
+       tmp = vmalloc_array(num_counters, sizeof(*tmp));
        if (!tmp)
                return -ENOMEM;
 
@@ -1526,7 +1526,7 @@ static int copy_counters_to_user(struct ebt_table *t,
        if (num_counters != nentries)
                return -EINVAL;
 
-       counterstmp = vmalloc(array_size(nentries, sizeof(*counterstmp)));
+       counterstmp = vmalloc_array(nentries, sizeof(*counterstmp));
        if (!counterstmp)
                return -ENOMEM;