Package: tinyproxy Version: 1.8.4-2 Severity: important Tags: upstream ipv6
Dear Maintainer, I specified two "Listen" directives in my tinyproxy.conf: Listen 0.0.0.0 Listen :: tinyproxy fails to properly handle those: If the first few requests arrive at the IPv4 listen the IPv6 listen fails and vice versa. This can easily be verified using strace. Directly after start tinyproxy select(2)s between FD 0 and FD 1: [pid 11352] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11351] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11350] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11349] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11348] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11347] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11346] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11345] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11344] select(2, [0 1], NULL, NULL, NULL <unfinished ...> [pid 11343] select(2, [0 1], NULL, NULL, NULL <unfinished ...> Once requests arrived tinyproxy either hangs in accept(2), because multiple children are being woken up, but only one can actually accept(2). Or they are in the select(2), but only select on FD 0: [pid 11352] select(2, [0], NULL, NULL, NULL <unfinished ...> [pid 11351] select(2, [0], NULL, NULL, NULL <unfinished ...> [pid 11350] accept(0, <unfinished ...> [pid 11349] accept(0, <unfinished ...> [pid 11348] accept(0, <unfinished ...> [pid 11347] accept(0, <unfinished ...> [pid 11346] accept(0, <unfinished ...> [pid 11345] accept(0, <unfinished ...> [pid 11344] accept(0, <unfinished ...> [pid 11343] accept(0, <unfinished ...> The issue with missing FD 1 in select(2) is, because tinyproxy does not reset rfds after the select: https://anonscm.debian.org/git/collab-maint/tinyproxy.git/tree/src/child.c#n234 If I am lucky I can achieve that a few children select on FD 0 and FD 1, but this is not reliable. Tinyproxy should be fixed like this: - Ensure that rfds is being reset after the select to ensure it selects on all sockets. - The accept race of the children should be prevented, to prevent the children from hanging in the accept(2) for a single socket. -- System Information: Debian Release: 9.4 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 4.9.0-6-amd64 (SMP w/1 CPU core) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages tinyproxy depends on: ii init-system-helpers 1.48 ii libc6 2.24-11+deb9u3 ii logrotate 3.11.0-0.1 ii lsb-base 9.20161125 tinyproxy recommends no packages. tinyproxy suggests no packages. -- Configuration Files: /etc/logrotate.d/tinyproxy changed [not included] /etc/tinyproxy/tinyproxy.conf changed [not included] -- no debconf information
