Add bounds checking to kgsl_sharedmem_find_region to ensure that GPU addresses supplied by the user via KGSL_IOCTL_SHAREMEM_FREE and KGSL_IOCTL_CFF_SYNCMEM are within a valid range for the MMU scheme of choice. CRs-Fixed: 380296 Change-Id: Ic0dedbadf40fca4a9e04ba075e67e08e617806b5 Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>