In the xz project repository, modifications by the backdoor author to block protection mechanisms continue to surface. A change was detected in the CMakeLists.txt build script that prevented the use of the Landlock application isolation mechanism, despite its support in the system. An unnecessary dot was intentionally added to the C code checking the availability of the Landlock system call, causing the Landlock check to fail under all conditions.
The change was added by Jia Tan on February 26, disguised as the implementation of an extended check for Landlock support. Previously, the output regarding Landlock support was based solely on the presence of the header file 'linux/landlock.h', but the change included a C test that additionally called prctl for verification. Due to the leading dot in the line, this code was non-functional, and the test always failed.
Source: opennet.ru
