V4L/DVB: ivtvfb: prevent reading uninitialized stack memory
V4L/DVB: ivtvfb: prevent reading uninitialized stack memory

The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16
bytes of uninitialized stack memory, because the "reserved" member of
the fb_vblank struct declared on the stack is not altered or zeroed
before being copied back to the user.  This patch takes care of it.

Signed-off-by: Dan Rosenberg <eae8df918674d018776356cca2a43d000e4169dc@gmail.com>
Signed-off-by: Andy Walls <87098e5036de39f00cafe8d8f6114135f55ad2e7@md.metrocast.net>
Signed-off-by: Mauro Carvalho Chehab <ad86ba2154032c9f55743a190faa2459a9d61d42@redhat.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas