Re: [PATCH 1/2] nvme-auth: Fix off by one checks

[Hannes Reinecke <hare@suse.de>]

On 7/18/22 13:09, Dan Carpenter wrote:
> The > ARRAY_SIZE() checks need to be >= ARRAY_SIZE() to prevent reading
> one element beyond the end of the arrays.
> 
> Fixes: a476416bb57b ("nvme: implement In-Band authentication")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> The MAINTAINERS file needs to be updated for this new code.
> 
>   drivers/nvme/common/auth.c | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/nvme/common/auth.c b/drivers/nvme/common/auth.c
> index 0c86ebce59d2..bfb16fec0aed 100644
> --- a/drivers/nvme/common/auth.c
> +++ b/drivers/nvme/common/auth.c
> @@ -55,7 +55,7 @@ static struct nvme_auth_dhgroup_map {
>   
>   const char *nvme_auth_dhgroup_name(u8 dhgroup_id)
>   {
> -	if ((dhgroup_id > ARRAY_SIZE(dhgroup_map)) ||
> +	if ((dhgroup_id >= ARRAY_SIZE(dhgroup_map)) ||
>   	    !dhgroup_map[dhgroup_id].name ||
>   	    !strlen(dhgroup_map[dhgroup_id].name))
>   		return NULL;
> @@ -65,7 +65,7 @@ EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_name);
>   
>   const char *nvme_auth_dhgroup_kpp(u8 dhgroup_id)
>   {
> -	if ((dhgroup_id > ARRAY_SIZE(dhgroup_map)) ||
> +	if ((dhgroup_id >= ARRAY_SIZE(dhgroup_map)) ||
>   	    !dhgroup_map[dhgroup_id].kpp ||
>   	    !strlen(dhgroup_map[dhgroup_id].kpp))
>   		return NULL;
> @@ -113,7 +113,7 @@ static struct nvme_dhchap_hash_map {
>   
>   const char *nvme_auth_hmac_name(u8 hmac_id)
>   {
> -	if ((hmac_id > ARRAY_SIZE(hash_map)) ||
> +	if ((hmac_id >= ARRAY_SIZE(hash_map)) ||
>   	    !hash_map[hmac_id].hmac ||
>   	    !strlen(hash_map[hmac_id].hmac))
>   		return NULL;
> @@ -123,7 +123,7 @@ EXPORT_SYMBOL_GPL(nvme_auth_hmac_name);
>   
>   const char *nvme_auth_digest_name(u8 hmac_id)
>   {
> -	if ((hmac_id > ARRAY_SIZE(hash_map)) ||
> +	if ((hmac_id >= ARRAY_SIZE(hash_map)) ||
>   	    !hash_map[hmac_id].digest ||
>   	    !strlen(hash_map[hmac_id].digest))
>   		return NULL;
> @@ -148,7 +148,7 @@ EXPORT_SYMBOL_GPL(nvme_auth_hmac_id);
>   
>   size_t nvme_auth_hmac_hash_len(u8 hmac_id)
>   {
> -	if ((hmac_id > ARRAY_SIZE(hash_map)) ||
> +	if ((hmac_id >= ARRAY_SIZE(hash_map)) ||
>   	    !hash_map[hmac_id].hmac ||
>   	    !strlen(hash_map[hmac_id].hmac))
>   		return 0;

Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
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