block: move CAP_SYS_ADMIN check in blkdev_roset()
Check for CAP_SYS_ADMIN before calling into the driver, similar to
blkdev_flushbuf(). This is safer and can spare a check in the driver.
(Currently BLKROSET is overridden by md and rbd, rbd is missing the
check. md has the check, but it covers a lot more than BLKROSET.)
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/ioctl.c b/block/ioctl.c
index c0fc32b..1668506 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -443,11 +443,12 @@
{
int ret, n;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
if (!is_unrecognized_ioctl(ret))
return ret;
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
if (get_user(n, (int __user *)arg))
return -EFAULT;
set_device_ro(bdev, n);