MIPS: boot: Fix unaligned access with CONFIG_MIPS_RAW_APPENDED_DTB

commit 4d4f9c1a17a3480f8fe523673f7232b254d724b7 upstream.

The compressed payload is not necesarily 4-byte aligned, at least when
compiling with Clang. In that case, the 4-byte value appended to the
compressed payload that corresponds to the uncompressed kernel image
size must be read using get_unaligned_le32().

This fixes Clang-built kernels not booting on MIPS (tested on a Ingenic
JZ4770 board).

Fixes: b8f54f2cde ("MIPS: ZBOOT: copy appended dtb to the end of the kernel")
Cc: <stable@vger.kernel.org> # v4.7
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Paul Cercueil 2020-12-16 23:39:56 +00:00 committed by Greg Kroah-Hartman
parent a650107de3
commit f5c2f79706

View File

@ -13,6 +13,7 @@
#include <linux/libfdt.h> #include <linux/libfdt.h>
#include <asm/addrspace.h> #include <asm/addrspace.h>
#include <asm/unaligned.h>
/* /*
* These two variables specify the free mem region * These two variables specify the free mem region
@ -113,7 +114,7 @@ void decompress_kernel(unsigned long boot_heap_start)
dtb_size = fdt_totalsize((void *)&__appended_dtb); dtb_size = fdt_totalsize((void *)&__appended_dtb);
/* last four bytes is always image size in little endian */ /* last four bytes is always image size in little endian */
image_size = le32_to_cpup((void *)&__image_end - 4); image_size = get_unaligned_le32((void *)&__image_end - 4);
/* copy dtb to where the booted kernel will expect it */ /* copy dtb to where the booted kernel will expect it */
memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size, memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,