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

[Greg KH]

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@xxxxxxxxxxxxx>
> Signed-off-by: Wei  Dong <weidong2@xxxxxxxxxxxxx>
> Signed-off-by: Junmin Zhao <zhaojunmin@xxxxxxxxxx>
> Reviewed-by: Zhuangluan Su <suzhuangluan@xxxxxxxxxxxxx>
> ---
>  drivers/android/binder.c | 2 ++
>  1 file changed, 2 insertions(+)

Why resend?  What changed from the previous version?

greg k-h