Re: [PATCH 08/10] powerpc/signal32: Convert restore_[tm]_user_regs() to user access block

[Guenter Roeck]

On Fri, Mar 19, 2021 at 11:06:57AM +0000, Christophe Leroy wrote:
> Convert restore_user_regs() and restore_tm_user_regs()
> to use user_access_read_begin/end blocks.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> ---
...
>  static long restore_user_regs(struct pt_regs *regs,
>  			      struct mcontext __user *sr, int sig)
>  {
...
> @@ -567,19 +569,22 @@ static long restore_user_regs(struct pt_regs *regs,
>  	regs->msr &= ~MSR_SPE;
>  	if (msr & MSR_SPE) {
>  		/* restore spe registers from the stack */
> -		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
> -				     ELF_NEVRREG * sizeof(u32)))
> -			return 1;
> +		unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
> +				      ELF_NEVRREG * sizeof(u32));

arch/powerpc/kernel/signal_32.c: In function 'restore_user_regs':
arch/powerpc/kernel/signal_32.c:565:36: error: macro "unsafe_copy_from_user" requires 4 arguments, but only 3 given

Guenter