V4L/DVB (5163): Add checks for CAP_SYS_ADMIN to VIDIOC_DBG_G_REGISTER
Before, root privileges were only needed to set hardware registers, not
to read them. On some hardware, reading from the wrong place at the
wrong time can hang the machine. So, to be consistent, root privileges
are required to read registers on all hardware.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/saa7115.c b/drivers/media/video/saa7115.c
index bb6aa13..7177721 100644
--- a/drivers/media/video/saa7115.c
+++ b/drivers/media/video/saa7115.c
@@ -1418,15 +1418,6 @@
#ifdef CONFIG_VIDEO_ADV_DEBUG
case VIDIOC_DBG_G_REGISTER:
- {
- struct v4l2_register *reg = arg;
-
- if (reg->i2c_id != I2C_DRIVERID_SAA711X)
- return -EINVAL;
- reg->val = saa711x_read(client, reg->reg & 0xff);
- break;
- }
-
case VIDIOC_DBG_S_REGISTER:
{
struct v4l2_register *reg = arg;
@@ -1435,7 +1426,10 @@
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
- saa711x_write(client, reg->reg & 0xff, reg->val & 0xff);
+ if (cmd == VIDIOC_DBG_G_REGISTER)
+ reg->val = saa711x_read(client, reg->reg & 0xff);
+ else
+ saa711x_write(client, reg->reg & 0xff, reg->val & 0xff);
break;
}
#endif