releases/4.8.7/android-binder-clear-binder-and-cookie-when-setting-handle-in-flat-binder-struct.patch

From 4afb604e2d14d429ac9e1fd84b952602853b2df5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com>
Date: Mon, 24 Oct 2016 15:20:30 +0200
Subject: ANDROID: binder: Clear binder and cookie when setting handle in flat binder struct
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From: Arve Hjønnevåg <arve@android.com>

commit 4afb604e2d14d429ac9e1fd84b952602853b2df5 upstream.

Prevents leaking pointers between processes

Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Martijn Coenen <maco@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/android/binder.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -1585,7 +1585,9 @@ static void binder_transaction(struct bi
 				fp->type = BINDER_TYPE_HANDLE;
 			else
 				fp->type = BINDER_TYPE_WEAK_HANDLE;
+			fp->binder = 0;
 			fp->handle = ref->desc;
+			fp->cookie = 0;
 			binder_inc_ref(ref, fp->type == BINDER_TYPE_HANDLE,
 				       &thread->todo);
 
@@ -1635,7 +1637,9 @@ static void binder_transaction(struct bi
 					return_error = BR_FAILED_REPLY;
 					goto err_binder_get_ref_for_node_failed;
 				}
+				fp->binder = 0;
 				fp->handle = new_ref->desc;
+				fp->cookie = 0;
 				binder_inc_ref(new_ref, fp->type == BINDER_TYPE_HANDLE, NULL);
 				trace_binder_transaction_ref_to_ref(t, ref,
 								    new_ref);
@@ -1689,6 +1693,7 @@ static void binder_transaction(struct bi
 			binder_debug(BINDER_DEBUG_TRANSACTION,
 				     "        fd %d -> %d\n", fp->handle, target_fd);
 			/* TODO: fput? */
+			fp->binder = 0;
 			fp->handle = target_fd;
 		} break;