Package: libc6 Version: 2.21 Severity: critical Justification: breaks unrelated software
Inter-process communication between a 64bit and a 32bit process is not working. At least pthread named semaphores are not working. A sem_wait is not awaken if a corresponding sem_post is done on the other side, which generated a dead lock. This problem only exists if a 64bit process communicates with a 32bit process but not for 32bit to 32bit communication or 64bit to 64bit communication. Moreover Debian 8.3 and all other tested distributions have no problem with 64bit to 32bit inter-process communication using pthread named semaphores. The problem seems to be related to the (new) FUTEX_PRIVATE_FLAG flag of futex. The sem_post command (for a named semaphore) seems to make a futex system call using the FUTEX_PRIVATE_FLAG which seems to be wrong. -- System Information: Debian Release: stretch/sid APT prefers testing APT policy: (900, 'testing'), (500, 'stable-updates'), (500, 'stable') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.3.0-1-amd64 (SMP w/8 CPU cores) Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/bash Init: systemd (via /run/systemd/system)