Re: [PATCH] riscv: uaccess: fix __put_kernel_nofault()

[Palmer Dabbelt]

On Sun, 01 Nov 2020 23:30:52 PST (-0800), changbin.du@xxxxxxxxx wrote:
> The copy_from_kernel_nofault() is broken on riscv because the 'dst' and
> 'src' are mistakenly reversed in __put_kernel_nofault() macro.
>
> copy_to_kernel_nofault:
> ...
> 0xffffffe0003159b8 <+30>:    sd      a4,0(a1) # a1 aka 'src'
>
> Fixes: d464118cdc ("riscv: implement __get_kernel_nofault and __put_user_nofault")
> Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxx>
> ---
>  arch/riscv/include/asm/uaccess.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
> index c47e6b35c551..824b2c9da75b 100644
> --- a/arch/riscv/include/asm/uaccess.h
> +++ b/arch/riscv/include/asm/uaccess.h
> @@ -476,7 +476,7 @@ do {									\
>  do {									\
>  	long __kr_err;							\
>  									\
> -	__put_user_nocheck(*((type *)(dst)), (type *)(src), __kr_err);	\
> +	__put_user_nocheck(*((type *)(src)), (type *)(dst), __kr_err);	\
>  	if (unlikely(__kr_err))						\
>  		goto err_label;						\
>  } while (0)

Thanks, this is on fixes.