Re: [PATCH v2] nvmem: u-boot-env: fix crc32_data_offset on redundant u-boot-env

From: Srinivas Kandagatla
Date: Fri Nov 11 2022 - 12:38:50 EST




On 04/11/2022 16:52, Christian Lamparter wrote:
The Western Digital MyBook Live (PowerPC 464/APM82181)
has a set of redundant u-boot-env. Loading up the driver
the following error:

| u_boot_env: Invalid calculated CRC32: 0x4f8f2c86 (expected: 0x98b14514)
| u_boot_env: probe of partition@1e000 failed with error -22

Looking up the userspace libubootenv utilities source [0],
it looks like the "mark" or "flag" is not part of the
crc32 sum... which is unfortunate :(

|static int libuboot_load(struct uboot_ctx *ctx)
|{
|[...]
| if (ctx->redundant) {
| [...]
| offsetdata = offsetof(struct uboot_env_redund, data);
| [...] //-----^^
| }
| usable_envsize = ctx->size - offsetdata;
| buf[0] = malloc(bufsize);
|[...]
| for (i = 0; i < copies; i++) {
| data = (uint8_t *)(buf[i] + offsetdata);
| uint32_t crc;
|
| ret = devread(ctx, i, buf[i]);
| [...]
| crc = *(uint32_t *)(buf[i] + offsetcrc);
| dev->crc = crc32(0, (uint8_t *)data, usable_envsize);
|

[0] https://github.com/sbabic/libubootenv/blob/master/src/uboot_env.c#L951
Fixes: d5542923f200 ("nvmem: add driver handling U-Boot environment variables")
Signed-off-by: Christian Lamparter <chunkeey@xxxxxxxxx>
---

Applied thanks,

--srini
v1->v2:
- drop endian crc32 check - handled by pending patch
- added u-boot-env: tag to subject + adjusted subject
---
drivers/nvmem/u-boot-env.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvmem/u-boot-env.c b/drivers/nvmem/u-boot-env.c
index 8e72d1bbd649..4fdbdccebda1 100644
--- a/drivers/nvmem/u-boot-env.c
+++ b/drivers/nvmem/u-boot-env.c
@@ -135,7 +135,7 @@ static int u_boot_env_parse(struct u_boot_env *priv)
break;
case U_BOOT_FORMAT_REDUNDANT:
crc32_offset = offsetof(struct u_boot_env_image_redundant, crc32);
- crc32_data_offset = offsetof(struct u_boot_env_image_redundant, mark);
+ crc32_data_offset = offsetof(struct u_boot_env_image_redundant, data);
data_offset = offsetof(struct u_boot_env_image_redundant, data);
break;
}