[PATCH 4.9 70/84] ANDROID: binder: fix proc->tsk check.

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Martijn Coenen <maco@xxxxxxxxxxx>

commit b2a6d1b999a4c13e5997bb864694e77172d45250 upstream.

Commit c4ea41ba195d ("binder: use group leader instead of open thread")'
was incomplete and didn't update a check in binder_mmap(), causing all
mmap() calls into the binder driver to fail.

Signed-off-by: Martijn Coenen <maco@xxxxxxxxxxx>
Tested-by: John Stultz <john.stultz@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/android/binder.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2875,7 +2875,7 @@ static int binder_mmap(struct file *filp
 	const char *failure_string;
 	struct binder_buffer *buffer;
 
-	if (proc->tsk != current)
+	if (proc->tsk != current->group_leader)
 		return -EINVAL;
 
 	if ((vma->vm_end - vma->vm_start) > SZ_4M)