__btrfs_free_extent in fs/btrfs/extent-tree.c in the Linux kernel through 5.3.12 calls btrfs_print_leaf in a certain ENOENT case, which allows local users to obtain potentially sensitive information about register values via the dmesg program. CREATE(Triage):(User=admin) CVE-2019-19039 (https://nvd.nist.gov/vuln/detail/CVE-2019-19039)