Use-after-free vulnerability in the disk_seqf_stop function in block/genhd.c in the Linux kernel before 4.7.1 allows local users to gain privileges by leveraging the execution of a certain stop operation even if the corresponding start operation had failed.
https://access.redhat.com/errata/RHSA-2017:1308
https://access.redhat.com/errata/RHSA-2017:1298
https://access.redhat.com/errata/RHSA-2017:1297
https://access.redhat.com/errata/RHSA-2017:0892
http://www.securityfocus.com/bid/94135