This function accidentally returns zero/success on the failure path.
It leads to locking issues and an uninitialized *map_copy in the
caller.

Fixes: b4b0193e83cb ("drm/fbdev-generic: Fix locking with drm_client_buffer_vmap_local()")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/gpu/drm/drm_client.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
index 2803ac111bbd..bfedcbf516db 100644
--- a/drivers/gpu/drm/drm_client.c
+++ b/drivers/gpu/drm/drm_client.c
@@ -355,7 +355,7 @@ int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,
 
 err_drm_gem_vmap_unlocked:
 	drm_gem_unlock(gem);
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL(drm_client_buffer_vmap_local);
 
-- 
2.43.0

Am 24.07.24 um 18:09 schrieb Dan Carpenter:
> This function accidentally returns zero/success on the failure path.
> It leads to locking issues and an uninitialized *map_copy in the
> caller.
>
> Fixes: b4b0193e83cb ("drm/fbdev-generic: Fix locking with drm_client_buffer_vmap_local()")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/gpu/drm/drm_client.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> index 2803ac111bbd..bfedcbf516db 100644
> --- a/drivers/gpu/drm/drm_client.c
> +++ b/drivers/gpu/drm/drm_client.c
> @@ -355,7 +355,7 @@ int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,
>   
>   err_drm_gem_vmap_unlocked:
>   	drm_gem_unlock(gem);
> -	return 0;
> +	return ret;
>   }
>   EXPORT_SYMBOL(drm_client_buffer_vmap_local);
>   

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

On 7/24/24 19:09, Dan Carpenter wrote:
> This function accidentally returns zero/success on the failure path.
> It leads to locking issues and an uninitialized *map_copy in the
> caller.
> 
> Fixes: b4b0193e83cb ("drm/fbdev-generic: Fix locking with drm_client_buffer_vmap_local()")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
>  drivers/gpu/drm/drm_client.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> index 2803ac111bbd..bfedcbf516db 100644
> --- a/drivers/gpu/drm/drm_client.c
> +++ b/drivers/gpu/drm/drm_client.c
> @@ -355,7 +355,7 @@ int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,
>  
>  err_drm_gem_vmap_unlocked:
>  	drm_gem_unlock(gem);
> -	return 0;
> +	return ret;
>  }
>  EXPORT_SYMBOL(drm_client_buffer_vmap_local);
>  

Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>

-- 
Best regards,
Dmitry