[PATCH 3/3] lib: sbi: fwft: Fix error return value for feature > 32 bits

[Xiang W]

在 2025-01-23四的 17:05 +0100，Clément Léger写道：
> Based on the spec, invalid feature should return SBI_ERR_INVALID_PARAM.
> This was not the case with the current implementation since the upper 32
> bits were not considered when checking the feature thus returning
> SBI_ERR_DENIED. Fix that by passing the raw unsigned long rather than
> the enum to be sure we are passing the full 64 bits and then check for
> upper bits to be cleared.
> 
> Signed-off-by: Clément Léger <cleger at rivosinc.com>
> ---
>  include/sbi/sbi_fwft.h |  4 ++--
>  lib/sbi/sbi_fwft.c     | 11 ++++++++---
>  2 files changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/include/sbi/sbi_fwft.h b/include/sbi/sbi_fwft.h
> index 2148820e..a9caa863 100644
> --- a/include/sbi/sbi_fwft.h
> +++ b/include/sbi/sbi_fwft.h
> @@ -14,9 +14,9 @@
>  
>  struct sbi_scratch;
>  
> -int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
> +int sbi_fwft_set(unsigned long feature, unsigned long value,
>  		 unsigned long flags);
> -int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val);
> +int sbi_fwft_get(unsigned long feature, unsigned long *out_val);
>  
>  int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot);
>  
> diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c
> index c46006d4..7bf86d6d 100644
> --- a/lib/sbi/sbi_fwft.c
> +++ b/lib/sbi/sbi_fwft.c
> @@ -287,12 +287,17 @@ static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature)
>  	return NULL;
>  }
>  
> -static int fwft_get_feature(enum sbi_fwft_feature_t feature,
> +static int fwft_get_feature(unsigned long feature,
>  			    struct fwft_config **conf)
>  {
>  	int ret;
>  	struct fwft_config *tconf;
>  
> +	/* Feature are defined as 32 bits identifiers */
> +	if (feature & ~(BIT(32) - 1)) {
The macro expansion of BIT(32) is 1UL<<32. In RV32, unsigned long is 32 bits, so
integer overflow will occur. It is recommended to replace BIT with BIT_ULL.

Regards,
Xiang W
> +		return SBI_EINVAL;
> +	}
> +
>  	tconf = get_feature_config(feature);
>  	if (!tconf) {
>  		if (fwft_is_defined_feature(feature))
> @@ -323,7 +328,7 @@ static void fwft_clear_config_lock(enum sbi_fwft_feature_t feature)
>  	conf->flags &= ~SBI_FWFT_SET_FLAG_LOCK;
>  }
>  
> -int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
> +int sbi_fwft_set(unsigned long feature, unsigned long value,
>  		 unsigned long flags)
>  {
>  	int ret;
> @@ -348,7 +353,7 @@ int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value,
>  	return SBI_OK;
>  }
>  
> -int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val)
> +int sbi_fwft_get(unsigned long feature, unsigned long *out_val)
>  {
>  	int ret;
>  	struct fwft_config *conf;
> -- 
> 2.47.1
> 
>