CVE ID:	CVE-2019-15793
Description:	In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, several locations which shift ids translate user/group ids before performing operations in the lower filesystem were translating them into init_user_ns, whereas they should have been translated into the s_user_ns for the lower filesystem. This resulted in using ids other than the intended ones in the lower fs, which likely did not map into the shifts s_user_ns. A local attacker could use this to possibly bypass discretionary access control permissions.
Test IDs:	None available
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2019-15793 https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=3644b9d5688da86f18e017c9c580b75cf52927bb https://usn.ubuntu.com/usn/usn-4183-1 https://usn.ubuntu.com/usn/usn-4184-1