2022-09-26 21:47:28

by Gustavo A. R. Silva

Subject: [PATCH][next] ath10k: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper

Zero-length arrays are deprecated and we are moving towards adopting
C99 flexible-array members, instead. So, replace zero-length arrays
declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
helper macro.

This helper allows for flexible-array members in unions.

Link: https://github.com/KSPP/linux/issues/193
Link: https://github.com/KSPP/linux/issues/212
Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/net/wireless/ath/ath10k/htt.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index f06cf39204e2..c051a22fce14 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -1108,8 +1108,10 @@ struct htt_rx_in_ord_ind {
u8 reserved;
__le16 msdu_count;
union {
- struct htt_rx_in_ord_msdu_desc msdu_descs32[0];
- struct htt_rx_in_ord_msdu_desc_ext msdu_descs64[0];
+ DECLARE_FLEX_ARRAY(struct htt_rx_in_ord_msdu_desc,
+ msdu_descs32);
+ DECLARE_FLEX_ARRAY(struct htt_rx_in_ord_msdu_desc_ext,
+ msdu_descs64);
} __packed;
} __packed;

--
2.34.1

2022-09-26 22:07:27

by Kees Cook

Subject: Re: [PATCH][next] ath10k: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper

On Mon, Sep 26, 2022 at 04:41:54PM -0500, Gustavo A. R. Silva wrote:
> Zero-length arrays are deprecated and we are moving towards adopting
> C99 flexible-array members, instead. So, replace zero-length arrays
> declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
> helper macro.
>
> This helper allows for flexible-array members in unions.
>
> Link: https://github.com/KSPP/linux/issues/193
> Link: https://github.com/KSPP/linux/issues/212
> Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
> Signed-off-by: Gustavo A. R. Silva <[email protected]>

Reviewed-by: Kees Cook <[email protected]>

--
Kees Cook

2022-09-28 07:52:36

by Kalle Valo

Subject: Re: [PATCH][next] ath10k: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper

"Gustavo A. R. Silva" <[email protected]> wrote:

> Zero-length arrays are deprecated and we are moving towards adopting
> C99 flexible-array members, instead. So, replace zero-length arrays
> declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
> helper macro.
>
> This helper allows for flexible-array members in unions.
>
> Link: https://github.com/KSPP/linux/issues/193
> Link: https://github.com/KSPP/linux/issues/212
> Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> Reviewed-by: Kees Cook <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

00d942e779c2 wifi: ath10k: Replace zero-length arrays with DECLARE_FLEX_ARRAY() helper

--
https://patchwork.kernel.org/project/linux-wireless/patch/YzIcoloIQBDqGlgc@work/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches