[PATCH net-next v2] netfilter: ebtables: replace zero-length array members

[PATCH net-next v2] netfilter: ebtables: replace zero-length array members

[GONG, Ruiqi]

From: "GONG, Ruiqi" <gongruiqi1@huawei.com>

As suggested by Kees[1], replace the old-style 0-element array members
of multiple structs in ebtables.h with modern C99 flexible array.

[1]: https://lore.kernel.org/all/5E8E0F9C-EE3F-4B0D-B827-DC47397E2A4A@kernel.org/

Link: https://github.com/KSPP/linux/issues/21
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---

v2: designate to net-next; cc more netdev maintainers

 include/uapi/linux/netfilter_bridge/ebtables.h | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/uapi/linux/netfilter_bridge/ebtables.h b/include/uapi/linux/netfilter_bridge/ebtables.h
index b0caad82b693..673b00df162c 100644
--- a/include/uapi/linux/netfilter_bridge/ebtables.h
+++ b/include/uapi/linux/netfilter_bridge/ebtables.h
@@ -87,7 +87,7 @@ struct ebt_entries {
 	/* nr. of entries */
 	unsigned int nentries;
 	/* entry list */
-	char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+	char data[] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 };
 
 /* used for the bitmask of struct ebt_entry */
@@ -129,7 +129,7 @@ struct ebt_entry_match {
 	} u;
 	/* size of data */
 	unsigned int match_size;
-	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+	unsigned char data[] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 };
 
 struct ebt_entry_watcher {
@@ -142,7 +142,7 @@ struct ebt_entry_watcher {
 	} u;
 	/* size of data */
 	unsigned int watcher_size;
-	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+	unsigned char data[] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 };
 
 struct ebt_entry_target {
@@ -155,7 +155,7 @@ struct ebt_entry_target {
 	} u;
 	/* size of data */
 	unsigned int target_size;
-	unsigned char data[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+	unsigned char data[] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 };
 
 #define EBT_STANDARD_TARGET "standard"
@@ -190,7 +190,7 @@ struct ebt_entry {
 		/* sizeof ebt_entry + matches + watchers + target */
 		unsigned int next_offset;
 	);
-	unsigned char elems[0] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
+	unsigned char elems[] __attribute__ ((aligned (__alignof__(struct ebt_replace))));
 };
 
 static __inline__ struct ebt_entry_target *
-- 
2.41.0

Re: [PATCH net-next v2] netfilter: ebtables: replace zero-length array members

[Simon Horman]

On Wed, Aug 16, 2023 at 05:34:43PM +0800, GONG, Ruiqi wrote:
> From: "GONG, Ruiqi" <gongruiqi1@huawei.com>
> 
> As suggested by Kees[1], replace the old-style 0-element array members
> of multiple structs in ebtables.h with modern C99 flexible array.
> 
> [1]: https://lore.kernel.org/all/5E8E0F9C-EE3F-4B0D-B827-DC47397E2A4A@kernel.org/
> 
> Link: https://github.com/KSPP/linux/issues/21
> Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> ---
> 
> v2: designate to net-next; cc more netdev maintainers

It's slightly unclear to me if this should be targeting
net-next or nf-next. But regardless, it doesn't seem
to apply cleanly to the main branch of either tree.

Please consider resolving that and posting again,
being sure to allow 24h before postings.

Link: https://www.kernel.org/doc/html/next/process/maintainer-netdev.html

-- 
pw-bot: changes-requested

Re: [PATCH net-next v2] netfilter: ebtables: replace zero-length array members

[Gong Ruiqi]

On 2023/08/16 19:16, Simon Horman wrote:
> On Wed, Aug 16, 2023 at 05:34:43PM +0800, GONG, Ruiqi wrote:
>> From: "GONG, Ruiqi" <gongruiqi1@huawei.com>
>>
>> As suggested by Kees[1], replace the old-style 0-element array members
>> of multiple structs in ebtables.h with modern C99 flexible array.
>>
>> [1]: https://lore.kernel.org/all/5E8E0F9C-EE3F-4B0D-B827-DC47397E2A4A@kernel.org/
>>
>> Link: https://github.com/KSPP/linux/issues/21
>> Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
>> Reviewed-by: Kees Cook <keescook@chromium.org>
>> ---
>>
>> v2: designate to net-next; cc more netdev maintainers
> 
> It's slightly unclear to me if this should be targeting
> net-next or nf-next. But regardless, it doesn't seem
> to apply cleanly to the main branch of either tree.

I find out that it's because this patch depends on a previous patch I've
just sent:

[v4] netfilter: ebtables: fix fortify warnings in size_entry_mwt()

Maybe I should make them two into a patch set? Otherwise if I adapt this
patch to net-next, it won't be applied either if the above patch is
applied ...

> 
> Please consider resolving that and posting again,
> being sure to allow 24h before postings.
> 
> Link: https://www.kernel.org/doc/html/next/process/maintainer-netdev.html
>