2018-01-19 19:18:00

by Liam Mark

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

Since the CMA API is now used directly the allocated memory is no longer
automatically zeroed.

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

Change-Id: I08e143707a0d31610821a7f16826c262bf3c1999
Signed-off-by: Liam Mark <[email protected]>
---
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 86196ff..91a9878 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

2018-01-19 20:17:02

by Dan Carpenter

Subject: Re: [PATCH] staging: android: ion: Zero CMA allocated memory

On Fri, Jan 19, 2018 at 11:16:47AM -0800, Liam Mark wrote:
> Since the CMA API is now used directly the allocated memory is no longer
> automatically zeroed.
>
> Explicitly zero CMA allocated memory to ensure that no data is exposed
> to userspace.
>
> Change-Id: I08e143707a0d31610821a7f16826c262bf3c1999

How do I use this Gerrit tag? I type it into
https://android-review.googlesource.com/ somewhere?

regards,
dan carpenter

2018-01-20 08:01:01

by Greg Kroah-Hartman

Subject: Re: [PATCH] staging: android: ion: Zero CMA allocated memory

On Fri, Jan 19, 2018 at 11:16:47AM -0800, Liam Mark wrote:
> Since the CMA API is now used directly the allocated memory is no longer
> automatically zeroed.
>
> Explicitly zero CMA allocated memory to ensure that no data is exposed
> to userspace.

How far back does this patch need to be ported? What is the git commit
id that caused this change to be needed? Please add it as a "Fixes:"
tag to the patch.

>
> Change-Id: I08e143707a0d31610821a7f16826c262bf3c1999

I'm guessing you didn't run scripts/checkpatch.pl on this patch :(

Please fix up and resend.

thanks,

greg k-h

2018-01-22 16:49:08

by Liam Mark

Subject: Re: [PATCH] staging: android: ion: Zero CMA allocated memory

On Fri, 19 Jan 2018, Dan Carpenter wrote:

> On Fri, Jan 19, 2018 at 11:16:47AM -0800, Liam Mark wrote:
> > Since the CMA API is now used directly the allocated memory is no longer
> > automatically zeroed.
> >
> > Explicitly zero CMA allocated memory to ensure that no data is exposed
> > to userspace.
> >
> > Change-Id: I08e143707a0d31610821a7f16826c262bf3c1999
>
> How do I use this Gerrit tag? I type it into
> https://android-review.googlesource.com/ somewhere?

Sorry, this tag won?t be any use to you, I will strip it out.

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

2018-01-22 16:53:37

by Liam Mark

Subject: Re: [PATCH] staging: android: ion: Zero CMA allocated memory

On Sat, 20 Jan 2018, Greg KH wrote:

> On Fri, Jan 19, 2018 at 11:16:47AM -0800, Liam Mark wrote:
> > Since the CMA API is now used directly the allocated memory is no longer
> > automatically zeroed.
> >
> > Explicitly zero CMA allocated memory to ensure that no data is exposed
> > to userspace.
>
> How far back does this patch need to be ported? What is the git commit
> id that caused this change to be needed? Please add it as a "Fixes:"
> tag to the patch.
>

It goes back to 204f672255c2 ("ion: Use CMA APIs directly"), I will update
the change.

> >
> > Change-Id: I08e143707a0d31610821a7f16826c262bf3c1999
>
> I'm guessing you didn't run scripts/checkpatch.pl on this patch :(
>
> Please fix up and resend.

Thanks, I will clean it up.

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