[dm-devel] [PATCH] dm ioctl: prevent stack leak in dm ioctl call

[Adrian Salido]

> On Tue, Apr 25, 2017 at 04:31:29PM -0700, Adrian Salido wrote:
>> Struct dm_ioctl has some padding/data that is not explicitly cleared
>> before copying to user. This can cause kernel stack contents to be
>> leaked to user space.
>
> Please be more precise here, explaining which part of the buffer
> and under exactly what circumstances you have found that uninitialised
> content gets returned to userspace.

it's actually the data portion of the struct under a custom user ioctl
where (param_kernel->data_size - minimum_data_size) <
sizeof(param_kernel->data)

Will update the patch to be clear