Re: [PATCH RESEND] android: binder: Sanity check at binder ioctl

[chenfeng <puck.chen@hisilicon.com>]

On 2016/1/19 16:35, Greg KH wrote:
> On Tue, Jan 19, 2016 at 03:49:27PM +0800, chenfeng wrote:
>>
>>
>> On 2016/1/19 15:33, Greg KH wrote:
>>> On Tue, Jan 19, 2016 at 11:45:36AM +0800, Chen Feng wrote:
>>>> When a process fork a child process, we should not allow the
>>>> child process use the binder which opened by parent process.
>>>>
>>>> But if the binder-object creater is a thread of one process who exit,
>>>> the other thread can also use this binder-object normally.
>>>> We can distinguish this by the member proc->tsk->mm.
>>>> If the thread exit the tsk->mm will be NULL.
>>>>
>>>> proc->tsk->mm != current->mm && proc->tsk->mm
>>>>
>>>> So only allow the shared mm_struct to use the same binder-object and
>>>> check the existence of mm_struct.
>>>>
>>>> Signed-off-by: Chen Feng <puck.chen@hisilicon.com>
>>>> Signed-off-by: Wei  Dong <weidong2@hisilicon.com>
>>>> Signed-off-by: Junmin Zhao <zhaojunmin@huawei.com>
>>>> Reviewed-by: Zhuangluan Su <suzhuangluan@hisilicon.com>
>>>> ---
>>>>  drivers/android/binder.c | 2 ++
>>>>  1 file changed, 2 insertions(+)
>>>
>>> Why resend?  What changed from the previous version?
>>>
>> My fault, it's my error commit.
>> mistake the current->mm with current->tsk->mm.
>> The robot-compile finds out this error.
> 
> Then please make it a 'v2' patch, and say what you changed, otherwise
> I'll assume it's identical to the first patch you sent in.
> 
> And how did you test the first patch if it couldn't even compile?
> 
It works well on our platform with hundreds of mobile phone.
Since our working branch is not mainline,and the patch is send for mainline
review.

I made a mistake while making the patch. I will send a new V2 for this patch.
Thanks!

> greg k-h
> 
> .
>