Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl

From	Arnd Bergmann <arnd@arndb.de>
Newsgroups	linux.kernel
Subject	Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl
Date	2015-12-30 15:00 +0100
Message-ID	<qLpse-7lJ-11@gated-at.bofh.it> (permalink)
References	<qGDvP-62G-11@gated-at.bofh.it> <qLmXo-5SI-11@gated-at.bofh.it> <qLoZc-79S-17@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wednesday 30 December 2015 21:24:21 Bamvor Jian Zhang wrote:
> diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c
> index 31bc7b7..9e98d01 100644
> --- a/drivers/char/ppdev.c
> +++ b/drivers/char/ppdev.c
> @@ -636,7 +636,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
>                 if ((time32[0] < 0) || (time32[1] < 0))
>                         return -EINVAL;
>  
> -               if (copy_to_user(time32, argp, sizeof(time32)))
> +               if (copy_to_user(argp, time32, sizeof(time32)))
>                         return -EFAULT;
>  
>                 return 0;
> @@ -648,7 +648,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
>                 if ((time64[0] < 0) || (time64[1] < 0))
>                         return -EINVAL;
>  
> -               if (copy_to_user(time64, argp, sizeof(time64)))
> +               if (copy_to_user(argp, time64, sizeof(time64)))
>                         return -EFAULT;
>  
>                 return 0;

This is something that would be caught by running 'make C=1' with 'sparse'
on your patch. Can you try that to see if you introduce any other warnings?

I'm guessing it's fine, but it would be nice to confirm. I also send a lot
of patches without running sparse and checkpatch first, but it's generally
a good idea.

	Arnd
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Thread

[PATCH v2 0/2] Convert ppdev to y2038 safe Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> - 2015-12-17 11:00 +0100
  [PATCH v2 1/2] ppdev: convert to y2038 safe Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> - 2015-12-17 11:00 +0100
  [PATCH v2 2/2] ppdev: add support for compat ioctl Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> - 2015-12-17 11:00 +0100
    Re: [PATCH v2 2/2] ppdev: add support for compat ioctl Arnd Bergmann <arnd@arndb.de> - 2015-12-18 00:20 +0100
      Re: [PATCH v2 2/2] ppdev: add support for compat ioctl Sudip Mukherjee <sudipm.mukherjee@gmail.com> - 2015-12-30 12:20 +0100
        Re: [PATCH v2 2/2] ppdev: add support for compat ioctl Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> - 2015-12-30 14:30 +0100
          Re: [PATCH v2 2/2] ppdev: add support for compat ioctl Sudip Mukherjee <sudipm.mukherjee@gmail.com> - 2015-12-30 14:50 +0100
          Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Arnd Bergmann <arnd@arndb.de> - 2015-12-30 15:00 +0100
            Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Bamvor Jian Zhang <bamvor.zhangjian@linaro.org> - 2015-12-30 15:30 +0100
              Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Sudip Mukherjee <sudipm.mukherjee@gmail.com> - 2015-12-31 10:50 +0100
                Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Arnd Bergmann <arnd@arndb.de> - 2015-12-31 15:20 +0100
                Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Sudip Mukherjee <sudipm.mukherjee@gmail.com> - 2016-01-01 06:10 +0100
                Re: [Y2038] [PATCH v2 2/2] ppdev: add support for compat ioctl Arnd Bergmann <arnd@arndb.de> - 2016-01-01 23:20 +0100

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