From 11032d745836280574827bb1db5e64a94945180e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com>
Date: Fri, 12 Aug 2016 16:04:28 -0700
Subject: [PATCH] ANDROID: binder: Clear binder and cookie when setting handle
 in flat binder struct
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Prevents leaking pointers between processes

BUG: 30768347
Change-Id: Id898076926f658a1b8b27a3ccb848756b36de4ca
Signed-off-by: Arve Hjønnevåg <arve@android.com>
---
 drivers/staging/android/binder.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index b13ed6dcca5d..e17c2667cda8 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -1628,7 +1628,9 @@ static void binder_transaction(struct binder_proc *proc,
 				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);
 
@@ -1673,7 +1675,9 @@ static void binder_transaction(struct binder_proc *proc,
 					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);
@@ -1725,6 +1729,7 @@ static void binder_transaction(struct binder_proc *proc,
 			binder_debug(BINDER_DEBUG_TRANSACTION,
 				     "        fd %d -> %d\n", fp->handle, target_fd);
 			/* TODO: fput? */
+			fp->binder = 0;
 			fp->handle = target_fd;
 		} break;
 
-- 
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