From a85f1a9de91a59cd9b12d60f631cbda9c56a1c3c Mon Sep 17 00:00:00 2001 From: Demi Marie Obenour Date: Sat, 3 Jun 2023 10:52:43 -0400 Subject: 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: Demi Marie Obenour Signed-off-by: Mike Snitzer --- drivers/md/dm-ioctl.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/md/dm-ioctl.c') diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index bfaebc02833a..e172a91e88dc 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -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; } -- cgit v1.2.3