[PATCH v2] staging: android: ion: Zero CMA allocated memory

From: Liam Mark <lmark@codeaurora.org>
To: Laura Abbott <labbott@redhat.com>,
	Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org,
	Dan Carpenter <dan.carpenter@oracle.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	linaro-mm-sig@lists.linaro.org
Subject: [PATCH v2] staging: android: ion: Zero CMA allocated memory
Date: Mon, 22 Jan 2018 09:46:41 -0800 (PST)	[thread overview]
Message-ID: <alpine.DEB.2.02.1801220940500.8950@lmark-linux.qualcomm.com> (raw)

Since commit 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
the CMA API is now used directly and therefore the allocated memory is no
longer automatically zeroed.

Explicitly zero CMA allocated memory to ensure that no data is exposed to
userspace.

Fixes: 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
Signed-off-by: Liam Mark <lmark@codeaurora.org>
---
Changes in v2:
  - Clean up the commit message.
  - Add 'Fixes:'

 drivers/staging/android/ion/ion_cma_heap.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c
index 86196ffd2faf..91a98785607a 100644
--- a/drivers/staging/android/ion/ion_cma_heap.c
+++ b/drivers/staging/android/ion/ion_cma_heap.c
@@ -51,6 +51,8 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
 	if (!pages)
 		return -ENOMEM;
 
+	memset(page_address(pages), 0, size);
+
 	table = kmalloc(sizeof(*table), GFP_KERNEL);
 	if (!table)
 		goto err;
-- 
1.8.5.2


Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
