Commit a85f1a9d authored by Demi Marie Obenour's avatar Demi Marie Obenour Committed by Mike Snitzer
Browse files

dm ioctl: Refuse to create device named "control" 



Typical userspace setups create a symlink under /dev/mapper with the
name of the device, but /dev/mapper/control is reserved for DM's control
device.  Therefore, trying to create such a device is almost certain to
be a userspace bug.

Signed-off-by: default avatarDemi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
parent 249bed82

drivers/md/dm-ioctl.c

+6 −1
Original line number Diff line number Diff line
@@ -767,7 +767,12 @@ static int get_target_version(struct file *filp, struct dm_ioctl *param, size_t 
static int check_name(const char *name)

{

	if (strchr(name, '/')) {

		DMERR("invalid device name");

		DMERR("device name cannot contain '/'");

		return -EINVAL;

	}



	if (strcmp(name, DM_CONTROL_NODE) == 0) {

		DMERR("device name cannot be \"%s\"", DM_CONTROL_NODE);

		return -EINVAL;

	}