platform/x86: ISST: Check for unaligned mmio address

mainline inclusion
from mainline-5.11
commit a552f204
category: bugfix
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I6FY06
CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a552f204b050b213b1e41a5134a0d2726c9a2ec1

Intel-SIG: commit a552f204 platform/x86: ISST: Check for unaligned
mmio address.
Backport SST missed patch for 5.10.

-------------------------------------------------

The address should be aligned to 4 byte boundary. So send an error for
unaligned address.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20201204015746.1168941-1-srinivas.pandruvada@linux.intel.comSigned-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: Nyingbao jia <yingbao.jia@intel.com>

drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c

@@ -42,6 +42,9 @@ static long isst_if_mmio_rd_wr(u8 *cmd_ptr, int *write_only, int resume)
 	if (io_reg->reg < 0x04 || io_reg->reg > 0xD0)
 		return -EINVAL;
 
+	if (io_reg->reg % 4)
+		return -EINVAL;
+
 	if (io_reg->read_write && !capable(CAP_SYS_ADMIN))
 		return -EPERM;