On 11/27/2012 06:25 PM, Bhushan Jain wrote: > Hello Developers, > > I am a student at Stony Brook University researching system security. > I noticed that the only reason dmcrypt-get-device (from eject package) needs setuid privilege is to read the major:minor numbers (unless I have missed something). > A lot of distributions (Ubuntu, Fedora, etc.) are trying to avoid use of the setuid bit because it can potentially introduce a privilege escalation attack vector. > I think the same thing could be accomplished by exporting the major:minor device numbers through a proc file, and then eliminate the need for dmcrypt-get-device. > I would be happy to send you a patch that does this, if there is interest. Any comments/thoughts? Hi, AFAIK eject package was deprecated and is moved into util-linux upstream (and almost completely rewritten). No idea what is dmcrypt-get-device, seems like distro specific hack. (And moreover, libblkid used in lsblk or blkid is better way to check UUID/major:minor etc. These run in user context.) BTW major:minor is in /sys for all block devices (lsblk uses this). So report it to distro you see this, definitely this should not need setuid bit! Milan _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
