[PATCH] nvmem: u-boot-env: fix crc32 casting type

Rafał Miłecki posted 1 patch 3 years, 7 months ago
drivers/nvmem/u-boot-env.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] nvmem: u-boot-env: fix crc32 casting type
Posted by Rafał Miłecki 3 years, 7 months ago
From: Rafał Miłecki <rafal@milecki.pl>

This fixes:
drivers/nvmem/u-boot-env.c:141:17: sparse: sparse: cast to restricted __le32

Reported-by: kernel test robot <lkp@intel.com>
Fixes: f955dc1445069 ("nvmem: add driver handling U-Boot environment variables")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 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 9b9abfb8f187..fb993ef4249f 100644
--- a/drivers/nvmem/u-boot-env.c
+++ b/drivers/nvmem/u-boot-env.c
@@ -138,7 +138,7 @@ static int u_boot_env_parse(struct u_boot_env *priv)
 		data_offset = offsetof(struct u_boot_env_image_redundant, data);
 		break;
 	}
-	crc32 = le32_to_cpu(*(uint32_t *)(buf + crc32_offset));
+	crc32 = le32_to_cpu(*(__le32 *)(buf + crc32_offset));
 	crc32_data_len = priv->mtd->size - crc32_data_offset;
 	data_len = priv->mtd->size - data_offset;
 
-- 
2.34.1

Re: [PATCH] nvmem: u-boot-env: fix crc32 casting type
Posted by Ahmad Fatoum 3 years, 7 months ago
Hello Rafał,

On 18.08.22 06:38, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
> 
> This fixes:
> drivers/nvmem/u-boot-env.c:141:17: sparse: sparse: cast to restricted __le32
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Fixes: f955dc1445069 ("nvmem: add driver handling U-Boot environment variables")
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
>  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 9b9abfb8f187..fb993ef4249f 100644
> --- a/drivers/nvmem/u-boot-env.c
> +++ b/drivers/nvmem/u-boot-env.c
> @@ -138,7 +138,7 @@ static int u_boot_env_parse(struct u_boot_env *priv)
>  		data_offset = offsetof(struct u_boot_env_image_redundant, data);
>  		break;
>  	}
> -	crc32 = le32_to_cpu(*(uint32_t *)(buf + crc32_offset));
> +	crc32 = le32_to_cpu(*(__le32 *)(buf + crc32_offset));

I had to do a double take to make sure alignment is not violated.
It's not, because crc32_offset is always zero.

How about rewriting this as

  /* CRC32 is always at offset 0 */
  crc32 = le32_to_cpup(buf);

To make the alignment clear to the reader?

>  	crc32_data_len = priv->mtd->size - crc32_data_offset;
>  	data_len = priv->mtd->size - data_offset;
>  

Cheers,
Ahmad

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