tree 08a8d1c55b554360c44dee4adb50c7e0ef2d43cb
parent c9ad1d9946e849ac3d8821d91e136d7fd728dec5
author Mark Yao <mark.yao@rock-chips.com> 1442982874 +0800
committer Mark Yao <mark.yao@rock-chips.com> 1453338845 +0800

drm/rockchip: fix wrong pitch/size using on gem

args->pitch and args->size may not be set by userspace, sometimes
userspace only malloc args and not memset args to zero, then
args->pitch and args->size is random, it is very danger to use
pitch/size on gem.

pitch's type is u32, and min_pitch's type is int, example,
pitch is 0xffffffff, then pitch < min_pitch return true, then gem will
alloc very very big bufffer, it would eat all the memory and cause kernel
crash.

Stop using pitch/size from args, calc them from other args.

Signed-off-by: Mark Yao <mark.yao@rock-chips.com>