[PATCH] drm/ttm: Use scnprintf() for avoiding potential buffer overflow

[Huang Rui]

On Wed, Mar 11, 2020 at 03:34:52PM +0800, Takashi Iwai wrote:
> Since snprintf() returns the would-be-output size instead of the
> actual output size, the succeeding calls may go beyond the given
> buffer limit.  Fix it by replacing with scnprintf().
> 
> Signed-off-by: Takashi Iwai <tiwai at suse.de>

Reviewed-by: Huang Rui <ray.huang at amd.com>

> ---
>  drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> index bf876faea592..faefaaef7909 100644
> --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
> @@ -604,7 +604,7 @@ static struct dma_pool *ttm_dma_pool_init(struct device *dev, gfp_t flags,
>  	p = pool->name;
>  	for (i = 0; i < ARRAY_SIZE(t); i++) {
>  		if (type & t[i]) {
> -			p += snprintf(p, sizeof(pool->name) - (p - pool->name),
> +			p += scnprintf(p, sizeof(pool->name) - (p - pool->name),
>  				      "%s", n[i]);
>  		}
>  	}
> -- 
> 2.16.4
>