[next] wifi: carl9170: Replace fake flex-array with flexible-array member

Message ID ZBSl2M+aGIO1fnuG@work
State New
Headers
Series [next] wifi: carl9170: Replace fake flex-array with flexible-array member |

Commit Message

Gustavo A. R. Silva March 17, 2023, 5:39 p.m. UTC
  Zero-length arrays as fake flexible arrays are deprecated and we are
moving towards adopting C99 flexible-array members instead.

Address the following warnings found with GCC-13 and
-fstrict-flex-arrays=3 enabled:
drivers/net/wireless/ath/carl9170/tx.c:702:61: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
drivers/net/wireless/ath/carl9170/tx.c:701:65: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

Link: https://github.com/KSPP/linux/issues/21
Link: https://github.com/KSPP/linux/issues/267
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 drivers/net/wireless/ath/carl9170/fwcmd.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
  

Comments

Christian Lamparter March 17, 2023, 7:11 p.m. UTC | #1
On 3/17/23 18:39, Gustavo A. R. Silva wrote:
> Zero-length arrays as fake flexible arrays are deprecated and we are
> moving towards adopting C99 flexible-array members instead.
> 
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> drivers/net/wireless/ath/carl9170/tx.c:702:61: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> drivers/net/wireless/ath/carl9170/tx.c:701:65: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
> 
> Link: https://github.com/KSPP/linux/issues/21
> Link: https://github.com/KSPP/linux/issues/267
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Christian Lamparter <chunkeey@gmail.com>

FYI: Also uploaded that patch to carl9170fw.git.

Cheers,
Christian
  
Kees Cook March 20, 2023, 5:38 p.m. UTC | #2
On Fri, Mar 17, 2023 at 11:39:36AM -0600, Gustavo A. R. Silva wrote:
> Zero-length arrays as fake flexible arrays are deprecated and we are
> moving towards adopting C99 flexible-array members instead.
> 
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> drivers/net/wireless/ath/carl9170/tx.c:702:61: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> drivers/net/wireless/ath/carl9170/tx.c:701:65: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
> 
> Link: https://github.com/KSPP/linux/issues/21
> Link: https://github.com/KSPP/linux/issues/267
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

This one threw me for a moment, but then realized the patch context
couldn't see the union that wrapped them. :)

Reviewed-by: Kees Cook <keescook@chromium.org>
  
Kalle Valo March 24, 2023, 2:54 p.m. UTC | #3
"Gustavo A. R. Silva" <gustavoars@kernel.org> wrote:

> Zero-length arrays as fake flexible arrays are deprecated and we are
> moving towards adopting C99 flexible-array members instead.
> 
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> drivers/net/wireless/ath/carl9170/tx.c:702:61: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> drivers/net/wireless/ath/carl9170/tx.c:701:65: warning: array subscript i is outside array bounds of ‘const struct _carl9170_tx_status[0]’ [-Warray-bounds=]
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
> 
> Link: https://github.com/KSPP/linux/issues/21
> Link: https://github.com/KSPP/linux/issues/267
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> Acked-by: Christian Lamparter <chunkeey@gmail.com>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>

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

1be3640cbb4a wifi: carl9170: Replace fake flex-array with flexible-array member
  

Patch

diff --git a/drivers/net/wireless/ath/carl9170/fwcmd.h b/drivers/net/wireless/ath/carl9170/fwcmd.h
index ff4b3b50250c..e5bcc364f088 100644
--- a/drivers/net/wireless/ath/carl9170/fwcmd.h
+++ b/drivers/net/wireless/ath/carl9170/fwcmd.h
@@ -320,9 +320,9 @@  struct carl9170_rsp {
 		struct carl9170_u32_list	rreg_res;
 		struct carl9170_u32_list	echo;
 #ifdef __CARL9170FW__
-		struct carl9170_tx_status	tx_status[0];
+		DECLARE_FLEX_ARRAY(struct carl9170_tx_status, tx_status);
 #endif /* __CARL9170FW__ */
-		struct _carl9170_tx_status	_tx_status[0];
+		DECLARE_FLEX_ARRAY(struct _carl9170_tx_status, _tx_status);
 		struct carl9170_gpio		gpio;
 		struct carl9170_tsf_rsp		tsf;
 		struct carl9170_psm		psm;