[PATCH] xtables: symmetric COMPAT_XT_ALIGN definition

[PATCH] xtables: symmetric COMPAT_XT_ALIGN definition

[Alexey Dobriyan]

Rewrite COMPAT_XT_ALIGN in terms of dummy structure hack.
Compat counters logically have nothing to do with it.
Use ALIGN() macro while I'm at it for same types.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

 include/linux/netfilter/x_tables.h |   13 +++++++++----
 net/netfilter/x_tables.c           |    4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -93,8 +93,7 @@ struct _xt_align {
 	__u64 u64;
 };
 
-#define XT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) 	\
-			& ~(__alignof__(struct _xt_align)-1))
+#define XT_ALIGN(s) ALIGN((s), __alignof__(struct _xt_align))
 
 /* Standard return verdict, or do jump. */
 #define XT_STANDARD_TARGET ""
@@ -571,8 +570,14 @@ struct compat_xt_counters_info {
 	struct compat_xt_counters counters[0];
 };
 
-#define COMPAT_XT_ALIGN(s) (((s) + (__alignof__(struct compat_xt_counters)-1)) \
-		& ~(__alignof__(struct compat_xt_counters)-1))
+struct _compat_xt_align {
+	__u8 u8;
+	__u16 u16;
+	__u32 u32;
+	compat_u64 u64;
+};
+
+#define COMPAT_XT_ALIGN(s) ALIGN((s), __alignof__(struct _compat_xt_align))
 
 extern void xt_compat_lock(u_int8_t af);
 extern void xt_compat_unlock(u_int8_t af);
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -364,7 +364,7 @@ int xt_check_match(struct xt_mtchk_param *par,
 		 * ebt_among is exempt from centralized matchsize checking
 		 * because it uses a dynamic-size data set.
 		 */
-		pr_err("%s_tables: %s match: invalid size %Zu != %u\n",
+		pr_err("%s_tables: %s match: invalid size %u != %u\n",
 		       xt_prefix[par->family], par->match->name,
 		       XT_ALIGN(par->match->matchsize), size);
 		return -EINVAL;
@@ -514,7 +514,7 @@ int xt_check_target(struct xt_tgchk_param *par,
 		    unsigned int size, u_int8_t proto, bool inv_proto)
 {
 	if (XT_ALIGN(par->target->targetsize) != size) {
-		pr_err("%s_tables: %s target: invalid size %Zu != %u\n",
+		pr_err("%s_tables: %s target: invalid size %u != %u\n",
 		       xt_prefix[par->family], par->target->name,
 		       XT_ALIGN(par->target->targetsize), size);
 		return -EINVAL;

Re: [PATCH] xtables: symmetric COMPAT_XT_ALIGN definition

[Jan Engelhardt]

On Friday 2010-02-05 23:13, Alexey Dobriyan wrote:

>Rewrite COMPAT_XT_ALIGN in terms of dummy structure hack.
>Compat counters logically have nothing to do with it.
>Use ALIGN() macro while I'm at it for same types.
>
>@@ -514,7 +514,7 @@ int xt_check_target(struct xt_tgchk_param *par,
> 		    unsigned int size, u_int8_t proto, bool inv_proto)
> {
> 	if (XT_ALIGN(par->target->targetsize) != size) {
>-		pr_err("%s_tables: %s target: invalid size %Zu != %u\n",
>+		pr_err("%s_tables: %s target: invalid size %u != %u\n",
> 		       xt_prefix[par->family], par->target->name,
> 		       XT_ALIGN(par->target->targetsize), size);
> 		return -EINVAL;
>@@ -364,7 +364,7 @@ int xt_check_match(struct xt_mtchk_param *par,
> 		 * ebt_among is exempt from centralized matchsize checking
> 		 * because it uses a dynamic-size data set.
> 		 */
>-		pr_err("%s_tables: %s match: invalid size %Zu != %u\n",
>+		pr_err("%s_tables: %s match: invalid size %u != %u\n",
> 		       xt_prefix[par->family], par->match->name,
> 		       XT_ALIGN(par->match->matchsize), size);
> 		return -EINVAL;

Why are you changing this? __alignof__ still returns a size_t,
and this type promotes through the course of the ALIGN macro.

Re: [PATCH] xtables: symmetric COMPAT_XT_ALIGN definition

[Alexey Dobriyan]

On Sat, Feb 06, 2010 at 12:22:54AM +0100, Jan Engelhardt wrote:
> On Friday 2010-02-05 23:13, Alexey Dobriyan wrote:
> >@@ -514,7 +514,7 @@ int xt_check_target(struct xt_tgchk_param *par,
> > 		    unsigned int size, u_int8_t proto, bool inv_proto)
> > {
> > 	if (XT_ALIGN(par->target->targetsize) != size) {
> >-		pr_err("%s_tables: %s target: invalid size %Zu != %u\n",
> >+		pr_err("%s_tables: %s target: invalid size %u != %u\n",
> > 		       xt_prefix[par->family], par->target->name,
> > 		       XT_ALIGN(par->target->targetsize), size);
> > 		return -EINVAL;
> >@@ -364,7 +364,7 @@ int xt_check_match(struct xt_mtchk_param *par,
> > 		 * ebt_among is exempt from centralized matchsize checking
> > 		 * because it uses a dynamic-size data set.
> > 		 */
> >-		pr_err("%s_tables: %s match: invalid size %Zu != %u\n",
> >+		pr_err("%s_tables: %s match: invalid size %u != %u\n",
> > 		       xt_prefix[par->family], par->match->name,
> > 		       XT_ALIGN(par->match->matchsize), size);
> > 		return -EINVAL;
> 
> Why are you changing this? __alignof__ still returns a size_t,
> and this type promotes through the course of the ALIGN macro.

alignment is casted to the type of alignee, so it's unsigned int now:

	#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)

Re: [PATCH] xtables: symmetric COMPAT_XT_ALIGN definition

[Patrick McHardy]

Alexey Dobriyan wrote:
> Rewrite COMPAT_XT_ALIGN in terms of dummy structure hack.
> Compat counters logically have nothing to do with it.
> Use ALIGN() macro while I'm at it for same types.

Also applied, thanks.