target/linux/bcm27xx/patches-4.19/950-0269-char-vcio-Add-compat-ioctl-handling.patch

   1 From 70194b474d22974cd46356e5b3d3b0582abd02da Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.org>
   3 Date: Thu, 24 Jan 2019 13:56:30 +0000
   4 Subject: [PATCH] char: vcio: Add compat ioctl handling
   5
   6 There was no compat ioctl handler, so 32 bit userspace on a
   7 64 bit kernel failed as IOCTL_MBOX_PROPERTY used the size
   8 of char*.
   9
  10 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
  11 ---
  12  drivers/char/broadcom/vcio.c | 22 +++++++++++++++++++++-
  13  1 file changed, 21 insertions(+), 1 deletion(-)
  14
  15 --- a/drivers/char/broadcom/vcio.c
  16 +++ b/drivers/char/broadcom/vcio.c
  17 @@ -24,6 +24,9 @@
  18
  19  #define VCIO_IOC_MAGIC 100
  20  #define IOCTL_MBOX_PROPERTY _IOWR(VCIO_IOC_MAGIC, 0, char *)
  21 +#ifdef CONFIG_COMPAT
  22 +#define IOCTL_MBOX_PROPERTY32 _IOWR(VCIO_IOC_MAGIC, 0, compat_uptr_t)
  23 +#endif
  24
  25  static struct {
  26         dev_t devt;
  27 @@ -87,13 +90,30 @@ static long vcio_device_ioctl(struct fil
  28         case IOCTL_MBOX_PROPERTY:
  29                 return vcio_user_property_list((void *)ioctl_param);
  30         default:
  31 -               pr_err("unknown ioctl: %d\n", ioctl_num);
  32 +               pr_err("unknown ioctl: %x\n", ioctl_num);
  33                 return -EINVAL;
  34         }
  35  }
  36
  37 +#ifdef CONFIG_COMPAT
  38 +static long vcio_device_compat_ioctl(struct file *file, unsigned int ioctl_num,
  39 +                                    unsigned long ioctl_param)
  40 +{
  41 +       switch (ioctl_num) {
  42 +       case IOCTL_MBOX_PROPERTY32:
  43 +               return vcio_user_property_list(compat_ptr(ioctl_param));
  44 +       default:
  45 +               pr_err("unknown ioctl: %x\n", ioctl_num);
  46 +               return -EINVAL;
  47 +       }
  48 +}
  49 +#endif
  50 +
  51  const struct file_operations vcio_fops = {
  52         .unlocked_ioctl = vcio_device_ioctl,
  53 +#ifdef CONFIG_COMPAT
  54 +       .compat_ioctl = vcio_device_compat_ioctl,
  55 +#endif
  56         .open = vcio_device_open,
  57         .release = vcio_device_release,
  58  };