The size of the imsf_slist_flex member is determined by imsf_numsrc, so
annotate it as such.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 include/uapi/linux/in.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h
index e682ab628dfa..445f6ae76f1e 100644
--- a/include/uapi/linux/in.h
+++ b/include/uapi/linux/in.h
@@ -199,7 +199,8 @@ struct ip_msfilter {
 	__u32		imsf_numsrc;
 	union {
 		__be32		imsf_slist[1];
-		__DECLARE_FLEX_ARRAY(__be32, imsf_slist_flex);
+		__DECLARE_FLEX_ARRAY_ATTR(__be32, imsf_slist_flex,
+					  __counted_by(imsf_numsrc));
 	};
 };
 
-- 
2.34.1

On Fri,  9 Feb 2024 17:16:42 -0800 Kees Cook wrote:
> The size of the imsf_slist_flex member is determined by imsf_numsrc, so
> annotate it as such.

Acked-by: Jakub Kicinski <kuba@kernel.org>

On 2/9/24 19:16, Kees Cook wrote:
> The size of the imsf_slist_flex member is determined by imsf_numsrc, so
> annotate it as such.
> 
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
> Cc: netdev@vger.kernel.org
> Cc: linux-hardening@vger.kernel.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

LGTM:

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks!
-- 
Gustavo

> ---
>   include/uapi/linux/in.h | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h
> index e682ab628dfa..445f6ae76f1e 100644
> --- a/include/uapi/linux/in.h
> +++ b/include/uapi/linux/in.h
> @@ -199,7 +199,8 @@ struct ip_msfilter {
>   	__u32		imsf_numsrc;
>   	union {
>   		__be32		imsf_slist[1];
> -		__DECLARE_FLEX_ARRAY(__be32, imsf_slist_flex);
> +		__DECLARE_FLEX_ARRAY_ATTR(__be32, imsf_slist_flex,
> +					  __counted_by(imsf_numsrc));
>   	};
>   };
>