diff mbox series

[v2,6/6] device-mapper: "." and ".." are not valid symlink names

Message ID 20230603145244.1538-7-demi@invisiblethingslab.com (mailing list archive)
State Accepted, archived
Delegated to: Mike Snitzer
Headers show
Series Several device-mapper fixes | expand

Commit Message

Demi Marie Obenour June 3, 2023, 2:52 p.m. UTC 
Using either of these is going to greatly confuse userspace, as they are
not valid symlink names and so creating the usual /dev/mapper/NAME
symlink will not be possible.  As creating a device with either of these
names is almost certainly a userspace bug, just error out.

Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
---
 drivers/md/dm-ioctl.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 5b647ab044e44b0c9d0961b5a336b41f50408f88..12be95ee20778b9acd3ea0d98f160a7409028afc 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -771,8 +771,10 @@  static int check_name(const char *name)
 		return -EINVAL;
 	}
 
-	if (strcmp(name, DM_CONTROL_NODE) == 0) {
-		DMERR("device name cannot be \"%s\"", DM_CONTROL_NODE);
+	if (strcmp(name, DM_CONTROL_NODE) == 0 ||
+	    strcmp(name, ".") == 0 ||
+	    strcmp(name, "..") == 0) {
+		DMERR("device name cannot be \"%s\", \".\", or \"..\"", DM_CONTROL_NODE);
 		return -EINVAL;
 	}