dm thin: Use last transaction's pmd->root when commit failed
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.9.337 by commit b35a22760aa5008d82533e59b0f0b5eb1b02d4e5, it was introduced in version v3.2 by commit 991d9fa02da0dd1f843dc011376965e0c8c6c9b5. For more details please see the references link.