linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Guo Ren <guoren@kernel.org>
To: "Dmitry V. Levin" <ldv@altlinux.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@redhat.com>, Kees Cook <keescook@chromium.org>,
	Andy Lutomirski <luto@amacapital.net>,
	Will Drewry <wad@chromium.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] csky: fix syscall_get_arguments() and syscall_set_arguments()
Date: Sat, 30 Mar 2019 08:49:49 +0800	[thread overview]
Message-ID: <20190330004949.GA15705@guoren-Inspiron-7460> (raw)
In-Reply-To: <20190329171230.GB32456@altlinux.org>

Thx Dmitry,

It works for me.

Tested-by: Guo Ren <ren_guo@c-sky.com>
Acked-by: Guo Ren <ren_guo@c-sky.com>

On Fri, Mar 29, 2019 at 08:12:30PM +0300, Dmitry V. Levin wrote:
> C-SKY syscall arguments are located in orig_a0,a1,a2,a3,regs[0],regs[1]
> fields of struct pt_regs.
> 
> Due to an off-by-one bug and a bug in pointer arithmetic
> syscall_get_arguments() was reading orig_a0,regs[1..5] fields instead.
> Likewise, syscall_set_arguments() was writing orig_a0,regs[1..5] fields
> instead.
> 
> Fixes: 4859bfca11c7d ("csky: System Call")
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Andy Lutomirski <luto@amacapital.net>
> Cc: Will Drewry <wad@chromium.org>
> Cc: stable@vger.kernel.org # v4.20+
> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> ---
>  arch/csky/include/asm/syscall.h | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/csky/include/asm/syscall.h b/arch/csky/include/asm/syscall.h
> index d637445737b7..9a9cd81e66c1 100644
> --- a/arch/csky/include/asm/syscall.h
> +++ b/arch/csky/include/asm/syscall.h
> @@ -49,10 +49,11 @@ syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
>  	if (i == 0) {
>  		args[0] = regs->orig_a0;
>  		args++;
> -		i++;
>  		n--;
> +	} else {
> +		i--;
>  	}
> -	memcpy(args, &regs->a1 + i * sizeof(regs->a1), n * sizeof(args[0]));
> +	memcpy(args, &regs->a1 + i, n * sizeof(args[0]));
>  }
>  
>  static inline void
> @@ -63,10 +64,11 @@ syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
>  	if (i == 0) {
>  		regs->orig_a0 = args[0];
>  		args++;
> -		i++;
>  		n--;
> +	} else {
> +		i--;
>  	}
> -	memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0));
> +	memcpy(&regs->a1 + i, args, n * sizeof(regs->a1));
>  }
>  
>  static inline int
> -- 
> ldv

      reply	other threads:[~2019-03-30  0:49 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-29 17:12 [PATCH] csky: fix syscall_get_arguments() and syscall_set_arguments() Dmitry V. Levin
2019-03-30  0:49 ` Guo Ren [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190330004949.GA15705@guoren-Inspiron-7460 \
    --to=guoren@kernel.org \
    --cc=keescook@chromium.org \
    --cc=ldv@altlinux.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=mingo@redhat.com \
    --cc=rostedt@goodmis.org \
    --cc=wad@chromium.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).