dm ioctl: validate name length when renaming
authorMilan Broz <mbroz@redhat.com>
Mon, 16 Mar 2009 16:56:01 +0000 (16:56 +0000)
committerAlasdair G Kergon <agk@redhat.com>
Mon, 16 Mar 2009 16:56:01 +0000 (16:56 +0000)
commitbc0fd67feba2e0770aad85393500ba77c6489f1c
tree898f91bc16492588dc74f191979dcca5462cdc36
parent5bee17f18b595937e6beafeee5197868a3f74a06
dm ioctl: validate name length when renaming

When renaming a mapped device validate the length of the new name.

The rename ioctl accepted any correctly-terminated string enclosed
within the data passed from userspace.  The other ioctls enforce a
size limit of DM_NAME_LEN.  If the name is changed and becomes longer
than that, the device can no longer be addressed by name.

Fix it by properly checking for device name length (including
terminating zero).

Cc: stable@kernel.org
Signed-off-by: Milan Broz <mbroz@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
drivers/md/dm-ioctl.c