From 226f86fea9bbf479294333c0bc11d55977f6557b Mon Sep 17 00:00:00 2001 From: Johannes Schauer Marin Rodrigues Date: Tue, 30 Aug 2022 21:55:57 +0200 Subject: [PATCH] fix mmdebstrap hanging if apt in download step failed (closes: #1017795) --- coverage.txt | 2 + mmdebstrap | 81 +++++++++++++++++++++--------------- tests/variant-custom-timeout | 11 +++++ 3 files changed, 60 insertions(+), 34 deletions(-) create mode 100644 tests/variant-custom-timeout diff --git a/coverage.txt b/coverage.txt index 290f076..88ac992 100644 --- a/coverage.txt +++ b/coverage.txt @@ -323,3 +323,5 @@ Modes: root unshare Needs-QEMU: true Test: error-if-stdout-is-tty + +Test: variant-custom-timeout diff --git a/mmdebstrap b/mmdebstrap index 9894a9e..fb7c412 100755 --- a/mmdebstrap +++ b/mmdebstrap @@ -979,46 +979,59 @@ sub run_apt_download_progress { my $flags = fcntl($wfh, F_GETFD, 0) or error "fcntl F_GETFD: $!"; fcntl($wfh, F_SETFD, $flags & ~FD_CLOEXEC) or error "fcntl F_SETFD: $!"; my $fd = fileno $wfh; - # 2022-05-02, #debian-apt on OFTC, times in UTC+2 - # 16:57 < josch> DonKult: how is -oDebug::pkgDpkgPm=1 -oDir::Log=/dev/null - # a "fancy no-op"? - # 11:52 < DonKult> josch: "fancy no-op" in sofar as it does nothing to the - # system even through its not in a special mode ala - # simulation or download-only. It does all the things it - # normally does, except that it just prints the dpkg calls - # instead of execv() them which in practice amounts means - # it does nothing (the Dir::Log just prevents libapt from - # creating the /var/log/apt directories. As the code - # creates them even if no logs will be placed there…). As - # said, midterm an apt --print-install-packages or - # something would be nice to avoid running everything. - run_apt_progress({ - ARGV => [ - 'apt-get', - '--yes', - '-oDebug::pkgDpkgPm=1', - '-oDir::Log=/dev/null', - $options->{dryrun} - ? '-oAPT::Get::Simulate=true' - : ( - "-oAPT::Keep-Fds::=$fd", - "-oDPkg::Tools::options::'cat >&$fd'::InfoFD=$fd", - "-oDpkg::Pre-Install-Pkgs::=cat >&$fd", - # no need to lock the database if we are just downloading - "-oDebug::NoLocking=1", - # no need for pty magic if we write no log - "-oDpkg::Use-Pty=0", - ), - @{ $options->{APT_ARGV} }, - ], - }); + # run_apt_progress() can raise an exception which would leave this function + # without cleaning up the other thread we started, making mmdebstrap hang + # in case run_apt_progress() fails -- so wrap this in eval() instead + eval { + # 2022-05-02, #debian-apt on OFTC, times in UTC+2 + # 16:57 < josch> DonKult: how is -oDebug::pkgDpkgPm=1 + # -oDir::Log=/dev/null a "fancy no-op"? + # 11:52 < DonKult> josch: "fancy no-op" in sofar as it does nothing to + # the system even through its not in a special mode + # ala simulation or download-only. It does all the + # things it normally does, except that it just prints + # the dpkg calls instead of execv() them which in + # practice amounts means it does nothing (the Dir::Log + # just prevents libapt from creating the /var/log/apt + # directories. As the code creates them even if no + # logs will be placed there…). As said, midterm an apt + # --print-install-packages or something would be nice + # to avoid running everything. + run_apt_progress({ + ARGV => [ + 'apt-get', + '--yes', + '-oDebug::pkgDpkgPm=1', + '-oDir::Log=/dev/null', + $options->{dryrun} + ? '-oAPT::Get::Simulate=true' + : ( + "-oAPT::Keep-Fds::=$fd", + "-oDPkg::Tools::options::'cat >&$fd'::InfoFD=$fd", + "-oDpkg::Pre-Install-Pkgs::=cat >&$fd", + # no need to lock the database if we are just downloading + "-oDebug::NoLocking=1", + # no need for pty magic if we write no log + "-oDpkg::Use-Pty=0", + ), + @{ $options->{APT_ARGV} }, + ], + }); + }; + my $err = ''; + if ($@) { + $err = "apt download failed: $@"; + } # signal the child process that we are done close $wfh; # and then read from it what it got my @listofdebs = <$fh>; close $fh; if ($? != 0) { - error "status child failed"; + $err = "status child failed"; + } + if ($err) { + error $err; } # remove trailing newlines chomp @listofdebs; diff --git a/tests/variant-custom-timeout b/tests/variant-custom-timeout new file mode 100644 index 0000000..06f0b42 --- /dev/null +++ b/tests/variant-custom-timeout @@ -0,0 +1,11 @@ +#!/bin/sh +set -eu +export LC_ALL=C.UTF-8 + +# mmdebstrap used to hang forever if apt in custom mode failed to resolve +# dependencies because a process died without cleaning up its children. +# https://bugs.debian.org/1017795 +ret=0 +{{ CMD }} --mode={{ MODE }} --variant=custom \ + --include=this-package-does-not-exist {{ DIST }} /dev/null {{ MIRROR }} || ret=1 +[ $ret -eq 1 ]