linux-hardening - Re: [PATCH] s390/vfio-ap: Replace one-element array with flexible array member

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <38a47dc9-7680-4321-b4c0-cf8b82ed1b43@linux.ibm.com>
Date: Wed, 29 Jan 2025 09:27:40 -0500
From: Anthony Krowiak <akrowiak@...ux.ibm.com>
To: Thorsten Blum <thorsten.blum@...ux.dev>,
        Halil Pasic
 <pasic@...ux.ibm.com>,
        Jason Herne <jjherne@...ux.ibm.com>,
        Harald Freudenberger <freude@...ux.ibm.com>,
        Holger Dengler <dengler@...ux.ibm.com>,
        Heiko Carstens <hca@...ux.ibm.com>, Vasily Gorbik <gor@...ux.ibm.com>,
        Alexander Gordeev
 <agordeev@...ux.ibm.com>,
        Christian Borntraeger <borntraeger@...ux.ibm.com>,
        Sven Schnelle <svens@...ux.ibm.com>
Cc: linux-hardening@...r.kernel.org, linux-s390@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] s390/vfio-ap: Replace one-element array with flexible
 array member




On 1/16/25 8:18 AM, Thorsten Blum wrote:
> Replace the deprecated one-element array with a modern flexible array
> member in the struct ap_matrix_dev.
>
> Use struct_size() to calculate the number of bytes to allocate for
> matrix_dev with a single mdev_type.
>
> Link: https://github.com/KSPP/linux/issues/79

LGTM:
Reviewed-by: Anthony Krowiak <akrowiak@...ux.ibm.com>

> Signed-off-by: Thorsten Blum <thorsten.blum@...ux.dev>
> ---
>   drivers/s390/crypto/vfio_ap_drv.c     | 2 +-
>   drivers/s390/crypto/vfio_ap_private.h | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
> index 67a807e2e75b..ea9ffa37f263 100644
> --- a/drivers/s390/crypto/vfio_ap_drv.c
> +++ b/drivers/s390/crypto/vfio_ap_drv.c
> @@ -96,7 +96,7 @@ static int vfio_ap_matrix_dev_create(void)
>   	if (ret)
>   		goto bus_register_err;
>   
> -	matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
> +	matrix_dev = kzalloc(struct_size(matrix_dev, mdev_types, 1), GFP_KERNEL);
>   	if (!matrix_dev) {
>   		ret = -ENOMEM;
>   		goto matrix_alloc_err;
> diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
> index 437a161c8659..9aed8994f567 100644
> --- a/drivers/s390/crypto/vfio_ap_private.h
> +++ b/drivers/s390/crypto/vfio_ap_private.h
> @@ -53,7 +53,7 @@ struct ap_matrix_dev {
>   	struct mutex guests_lock; /* serializes access to each KVM guest */
>   	struct mdev_parent parent;
>   	struct mdev_type mdev_type;
> -	struct mdev_type *mdev_types[1];
> +	struct mdev_type *mdev_types[];
>   };
>   
>   extern struct ap_matrix_dev *matrix_dev;