2023-05-23 11:41:32

by Arnd Bergmann

Subject: [PATCH] rtw89: use flexible array member in rtw89_btc_btf_tlv

From: Arnd Bergmann <[email protected]>

struct rtw89_btc_btf_tlv contains a one-byte member that is intended as a
flexible array:

In function 'fortify_memcpy_chk',
inlined from '_append_tdma' at drivers/net/wireless/realtek/rtw89/coex.c:1579:3:
include/linux/fortify-string.h:583:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
583 | __write_overflow_field(p_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Make this actually use a flexible array to let the compiler understand.

Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/net/wireless/realtek/rtw89/coex.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtw89/coex.c b/drivers/net/wireless/realtek/rtw89/coex.c
index 3a586a971e8f..bda0e1e99a8c 100644
--- a/drivers/net/wireless/realtek/rtw89/coex.c
+++ b/drivers/net/wireless/realtek/rtw89/coex.c
@@ -206,7 +206,7 @@ static const struct rtw89_btc_ver rtw89_btc_ver_defs[] = {
struct rtw89_btc_btf_tlv {
u8 type;
u8 len;
- u8 val[1];
+ u8 val[];
} __packed;

enum btc_btf_set_report_en {
--
2.39.2

2023-05-24 01:30:47

by Ping-Ke Shih

Subject: RE: [PATCH] rtw89: use flexible array member in rtw89_btc_btf_tlv

> -----Original Message-----
> From: Arnd Bergmann <[email protected]>
> Sent: Tuesday, May 23, 2023 7:33 PM
> To: Ping-Ke Shih <[email protected]>; Kalle Valo <[email protected]>
> Cc: Arnd Bergmann <[email protected]>; DeanKu <[email protected]>; [email protected];
> [email protected]
> Subject: [PATCH] rtw89: use flexible array member in rtw89_btc_btf_tlv
>
> From: Arnd Bergmann <[email protected]>
>
> struct rtw89_btc_btf_tlv contains a one-byte member that is intended as a
> flexible array:
>
> In function 'fortify_memcpy_chk',
> inlined from '_append_tdma' at drivers/net/wireless/realtek/rtw89/coex.c:1579:3:
> include/linux/fortify-string.h:583:25: error: call to '__write_overflow_field' declared with attribute
> warning: detected write beyond size of field (1st parameter); maybe use struct_group()?
> [-Werror=attribute-warning]
> 583 | __write_overflow_field(p_size_field, size);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Make this actually use a flexible array to let the compiler understand.
>
> Signed-off-by: Arnd Bergmann <[email protected]>

Reviewed-by: Ping-Ke Shih <[email protected]>

> ---
> drivers/net/wireless/realtek/rtw89/coex.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/realtek/rtw89/coex.c b/drivers/net/wireless/realtek/rtw89/coex.c
> index 3a586a971e8f..bda0e1e99a8c 100644
> --- a/drivers/net/wireless/realtek/rtw89/coex.c
> +++ b/drivers/net/wireless/realtek/rtw89/coex.c
> @@ -206,7 +206,7 @@ static const struct rtw89_btc_ver rtw89_btc_ver_defs[] = {
> struct rtw89_btc_btf_tlv {
> u8 type;
> u8 len;
> - u8 val[1];
> + u8 val[];
> } __packed;
>
> enum btc_btf_set_report_en {
> --
> 2.39.2

2023-05-25 16:15:39

by Kalle Valo

Subject: Re: wifi: rtw89: use flexible array member in rtw89_btc_btf_tlv

Arnd Bergmann <[email protected]> wrote:

> From: Arnd Bergmann <[email protected]>
>
> struct rtw89_btc_btf_tlv contains a one-byte member that is intended as a
> flexible array:
>
> In function 'fortify_memcpy_chk',
> inlined from '_append_tdma' at drivers/net/wireless/realtek/rtw89/coex.c:1579:3:
> include/linux/fortify-string.h:583:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning]
> 583 | __write_overflow_field(p_size_field, size);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Make this actually use a flexible array to let the compiler understand.
>
> Signed-off-by: Arnd Bergmann <[email protected]>
> Reviewed-by: Ping-Ke Shih <[email protected]>
> Reviewed-by: Gustavo A. R. Silva <[email protected]>

Patch applied to wireless-next.git, thanks.

47e612268ea0 wifi: rtw89: use flexible array member in rtw89_btc_btf_tlv

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

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