[v1] drm/imagination: Use memdup_user() helper

[PATCH -next] drm/imagination: Use memdup_user() helper

Posted by Jinjie Ruan 1 year, 5 months ago

Switching to memdup_user(), which combines kmalloc() and copy_from_user(),
and it can simplfy code.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
 drivers/gpu/drm/imagination/pvr_context.c | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/imagination/pvr_context.c b/drivers/gpu/drm/imagination/pvr_context.c
index eded5e955cc0..e75fd50a4d9f 100644
--- a/drivers/gpu/drm/imagination/pvr_context.c
+++ b/drivers/gpu/drm/imagination/pvr_context.c
@@ -69,27 +69,19 @@ process_static_context_state(struct pvr_device *pvr_dev, const struct pvr_stream
 	void *stream;
 	int err;
 
-	stream = kzalloc(stream_size, GFP_KERNEL);
-	if (!stream)
-		return -ENOMEM;
-
-	if (copy_from_user(stream, u64_to_user_ptr(stream_user_ptr), stream_size)) {
-		err = -EFAULT;
-		goto err_free;
-	}
+	stream = memdup_user(u64_to_user_ptr(stream_user_ptr), stream_size);
+	if (IS_ERR(stream))
+		return PTR_ERR(stream);
 
 	err = pvr_stream_process(pvr_dev, cmd_defs, stream, stream_size, dest);
-	if (err)
-		goto err_free;
+	if (err) {
+		kfree(stream);
+		return err;
+	}
 
 	kfree(stream);
 
 	return 0;
-
-err_free:
-	kfree(stream);
-
-	return err;
 }
 
 static int init_render_fw_objs(struct pvr_context *ctx,
-- 
2.34.1

Re: [PATCH -next] drm/imagination: Use memdup_user() helper

Posted by Christophe JAILLET 1 year, 5 months ago

Le 31/08/2024 à 12:30, Jinjie Ruan a écrit :
> Switching to memdup_user(), which combines kmalloc() and copy_from_user(),
> and it can simplfy code.
> 
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> ---
>   drivers/gpu/drm/imagination/pvr_context.c | 22 +++++++---------------
>   1 file changed, 7 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/imagination/pvr_context.c b/drivers/gpu/drm/imagination/pvr_context.c
> index eded5e955cc0..e75fd50a4d9f 100644
> --- a/drivers/gpu/drm/imagination/pvr_context.c
> +++ b/drivers/gpu/drm/imagination/pvr_context.c
> @@ -69,27 +69,19 @@ process_static_context_state(struct pvr_device *pvr_dev, const struct pvr_stream
>   	void *stream;
>   	int err;
>   
> -	stream = kzalloc(stream_size, GFP_KERNEL);
> -	if (!stream)
> -		return -ENOMEM;
> -
> -	if (copy_from_user(stream, u64_to_user_ptr(stream_user_ptr), stream_size)) {
> -		err = -EFAULT;
> -		goto err_free;
> -	}
> +	stream = memdup_user(u64_to_user_ptr(stream_user_ptr), stream_size);
> +	if (IS_ERR(stream))
> +		return PTR_ERR(stream);
>   
>   	err = pvr_stream_process(pvr_dev, cmd_defs, stream, stream_size, dest);
> -	if (err)
> -		goto err_free;
> +	if (err) {
> +		kfree(stream);
> +		return err;
> +	}
>   
>   	kfree(stream);
>   
>   	return 0;
> -
> -err_free:
> -	kfree(stream);
> -
> -	return err;
>   }

It could also be:
  	err = pvr_stream_process(...);

  	kfree(stream);

  	return err;

as you did for drivers/gpu/drm/imagination/pvr_job.c.

CJ

>   
>   static int init_render_fw_objs(struct pvr_context *ctx,

Re: [PATCH -next] drm/imagination: Use memdup_user() helper

Posted by Jinjie Ruan 1 year, 5 months ago


On 2024/8/31 18:48, Christophe JAILLET wrote:
> Le 31/08/2024 à 12:30, Jinjie Ruan a écrit :
>> Switching to memdup_user(), which combines kmalloc() and
>> copy_from_user(),
>> and it can simplfy code.
>>
>> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
>> ---
>>   drivers/gpu/drm/imagination/pvr_context.c | 22 +++++++---------------
>>   1 file changed, 7 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/imagination/pvr_context.c
>> b/drivers/gpu/drm/imagination/pvr_context.c
>> index eded5e955cc0..e75fd50a4d9f 100644
>> --- a/drivers/gpu/drm/imagination/pvr_context.c
>> +++ b/drivers/gpu/drm/imagination/pvr_context.c
>> @@ -69,27 +69,19 @@ process_static_context_state(struct pvr_device
>> *pvr_dev, const struct pvr_stream
>>       void *stream;
>>       int err;
>>   -    stream = kzalloc(stream_size, GFP_KERNEL);
>> -    if (!stream)
>> -        return -ENOMEM;
>> -
>> -    if (copy_from_user(stream, u64_to_user_ptr(stream_user_ptr),
>> stream_size)) {
>> -        err = -EFAULT;
>> -        goto err_free;
>> -    }
>> +    stream = memdup_user(u64_to_user_ptr(stream_user_ptr), stream_size);
>> +    if (IS_ERR(stream))
>> +        return PTR_ERR(stream);
>>         err = pvr_stream_process(pvr_dev, cmd_defs, stream,
>> stream_size, dest);
>> -    if (err)
>> -        goto err_free;
>> +    if (err) {
>> +        kfree(stream);
>> +        return err;
>> +    }
>>         kfree(stream);
>>         return 0;
>> -
>> -err_free:
>> -    kfree(stream);
>> -
>> -    return err;
>>   }
> 
> It could also be:
>      err = pvr_stream_process(...);
> 
>      kfree(stream);
> 
>      return err;
> 
> as you did for drivers/gpu/drm/imagination/pvr_job.c.

You are right! that will be more clean.

> 
> CJ
> 
>>     static int init_render_fw_objs(struct pvr_context *ctx,
> 
>