Re: [PATCH] media: vb2: add length check for mmap

[김승우 <sw0312.kim@samsung.com>]

Oops, there is a issue.

vb2-core does not PAGE_ALIGN to length of buffer, but mmap() always do
PAGE_ALIGN to its length.

So non PAGE_ALIGN length of buffer from driver side can not mmaped with
this patch.

On 2013년 04월 12일 15:03, Marek Szyprowski wrote:
> 
> On 4/12/2013 5:57 AM, Seung-Woo Kim wrote:
>> The length of mmap() can be bigger than length of vb2 buffer, so
>> it should be checked.
>>
>> Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
> 
> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
> 
>> ---
>>   drivers/media/v4l2-core/videobuf2-core.c |    5 +++++
>>   1 files changed, 5 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/media/v4l2-core/videobuf2-core.c
>> b/drivers/media/v4l2-core/videobuf2-core.c
>> index db1235d..2c6ff2d 100644
>> --- a/drivers/media/v4l2-core/videobuf2-core.c
>> +++ b/drivers/media/v4l2-core/videobuf2-core.c
>> @@ -1886,6 +1886,11 @@ int vb2_mmap(struct vb2_queue *q, struct
>> vm_area_struct *vma)
>>         vb = q->bufs[buffer];
>>   +    if (vb->v4l2_planes[plane].length < (vma->vm_end -
>> vma->vm_start)) {
>> +        dprintk(1, "Invalid length\n");
>> +        return -EINVAL;
>> +    }
>> +
>>       ret = call_memop(q, mmap, vb->planes[plane].mem_priv, vma);
>>       if (ret)
>>           return ret;
> 
> Best regards

-- 
Seung-Woo Kim
Samsung Software R&D Center
--