diff mbox series

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

Message ID ZAZT11n4q5bBttW0@work
State New
Headers
Series [next] rxrpc: Replace fake flex-array with flexible-array member |

Commit Message

Gustavo A. R. Silva March 6, 2023, 8:57 p.m. UTC 
  Zero-length arrays as fake flexible arrays are deprecated and we are
moving towards adopting C99 flexible-array members instead.

Transform zero-length array into flexible-array member in struct
rxrpc_ackpacket.

Address the following warnings found with GCC-13 and
-fstrict-flex-arrays=3 enabled:
net/rxrpc/call_event.c:149:38: warning: array subscript i is outside array bounds of ‘uint8_t[0]’ {aka ‘unsigned char[]’} [-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/263
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 net/rxrpc/protocol.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Simon Horman March 7, 2023, 3:46 p.m. UTC | #1 
On Mon, Mar 06, 2023 at 02:57:59PM -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.
> 
> Transform zero-length array into flexible-array member in struct
> rxrpc_ackpacket.
> 
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> net/rxrpc/call_event.c:149:38: warning: array subscript i is outside array bounds of ‘uint8_t[0]’ {aka ‘unsigned char[]’} [-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/263
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Kees Cook March 20, 2023, 5:39 p.m. UTC | #2 
On Mon, Mar 06, 2023 at 02:57:59PM -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.
> 
> Transform zero-length array into flexible-array member in struct
> rxrpc_ackpacket.
> 
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> net/rxrpc/call_event.c:149:38: warning: array subscript i is outside array bounds of ‘uint8_t[0]’ {aka ‘unsigned char[]’} [-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/263
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Reviewed-by: Kees Cook <keescook@chromium.org>
Gustavo A. R. Silva March 30, 2023, 8:15 p.m. UTC | #3 
Hi all,

Friendly ping: who can take this, please? 😄

Thanks
Jeffrey E Altman April 21, 2023, 1 p.m. UTC | #4 
On 3/6/2023 3:57 PM, 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.
>
> Transform zero-length array into flexible-array member in struct
> rxrpc_ackpacket.
>
> Address the following warnings found with GCC-13 and
> -fstrict-flex-arrays=3 enabled:
> net/rxrpc/call_event.c:149:38: warning: array subscript i is outside array bounds of ‘uint8_t[0]’ {aka ‘unsigned char[]’} [-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/263
> Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> ---
>   net/rxrpc/protocol.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/rxrpc/protocol.h b/net/rxrpc/protocol.h
> index 6760cb99c6d6..e8ee4af43ca8 100644
> --- a/net/rxrpc/protocol.h
> +++ b/net/rxrpc/protocol.h
> @@ -126,7 +126,7 @@ struct rxrpc_ackpacket {
>   	uint8_t		nAcks;		/* number of ACKs */
>   #define RXRPC_MAXACKS	255
>   
> -	uint8_t		acks[0];	/* list of ACK/NAKs */
> +	uint8_t		acks[];		/* list of ACK/NAKs */
>   #define RXRPC_ACK_TYPE_NACK		0
>   #define RXRPC_ACK_TYPE_ACK		1
>   

Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
diff mbox series

Patch

diff --git a/net/rxrpc/protocol.h b/net/rxrpc/protocol.h
index 6760cb99c6d6..e8ee4af43ca8 100644
--- a/net/rxrpc/protocol.h
+++ b/net/rxrpc/protocol.h
@@ -126,7 +126,7 @@  struct rxrpc_ackpacket {
 	uint8_t		nAcks;		/* number of ACKs */
 #define RXRPC_MAXACKS	255
 
-	uint8_t		acks[0];	/* list of ACK/NAKs */
+	uint8_t		acks[];		/* list of ACK/NAKs */
 #define RXRPC_ACK_TYPE_NACK		0
 #define RXRPC_ACK_TYPE_ACK		1