| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.4 08/76] MIPS: boot: Fix unaligned access with CONFIG_MIPS_RAW_APPENDED_DTB | Date | Mon, 18 Jan 2021 12:34:08 +0100 |
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From: Paul Cercueil <paul@crapouillou.net>
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: b8f54f2cde78 ("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>
--- arch/mips/boot/compressed/decompress.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/mips/boot/compressed/decompress.c +++ b/arch/mips/boot/compressed/decompress.c @@ -13,6 +13,7 @@ #include <linux/libfdt.h> #include <asm/addrspace.h> +#include <asm/unaligned.h> /* * These two variables specify the free mem region @@ -113,7 +114,7 @@ void decompress_kernel(unsigned long boo dtb_size = fdt_totalsize((void *)&__appended_dtb); /* 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 */ memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
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