From: Linus Walleij Date: Mon, 11 Mar 2019 18:16:42 +0000 (+0100) Subject: kernel: mtdsplit: wrgg: Support big and little endian X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=b907097291af843f714139999c32107463b2ef4a;p=openwrt%2Fstaging%2Fthess.git kernel: mtdsplit: wrgg: Support big and little endian The WRGG images exist in both big and little endian variants, as can be seen from the image generator in tools/firmware-utils/src/mkwrggimg.c, you either pass the "-b" flag or not. The D-Link DIR-685 is using little endian images so we need to support splitting these. Detect endianness like this: if the kernel entity size gets silly big (bigger than the flash memory) we are probably using the wrong endianness. Example: my kernel of 0x0067ff64 was switched around by wrong endianness and detected as 0x64ff67a0 (the actual size in swapped endianness + header 0xa0). Signed-off-by: Linus Walleij Signed-off-by: Christian Lamparter --- diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c index 5ce7625731..6c137c52ec 100644 --- a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c +++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_wrgg.c @@ -72,6 +72,16 @@ static int mtdsplit_parse_wrgg(struct mtd_info *master, /* sanity checks */ if (le32_to_cpu(hdr.magic1) == WRGG03_MAGIC) { kernel_ent_size = hdr_len + be32_to_cpu(hdr.size); + /* + * If this becomes silly big it's probably because the + * WRGG image is little-endian. + */ + if (kernel_ent_size > master->size) + kernel_ent_size = hdr_len + le32_to_cpu(hdr.size); + + /* Now what ?! It's neither */ + if (kernel_ent_size > master->size) + return -EINVAL; } else if (le32_to_cpu(hdr.magic1) == WRG_MAGIC) { kernel_ent_size = sizeof(struct wrg_header) + le32_to_cpu( ((struct wrg_header*)&hdr)->size);