Bug 31528

apt-0.5.15lorg2-alt52

apt breaks on too long lines in comments (probably, around 512).

Here is an example -- I have created /etc/apt/apt.conf.d/bad-comment.conf with 530 As:

/*
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
*/

All APT programs now hang like this:

# strace -e trace=file -fF apt-config dump
execve("/usr/bin/apt-config", ["apt-config", "dump"], [/* 38 vars */]) = 0
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/libapt-pkg-libc6.9-6.so.5", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/libstdc++.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libgcc_s.so.1", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/librpm-4.0.4.so", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/librpmio-4.0.4.so", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/librpmdb-4.0.4.so", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/liblua-5.1.so.0", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libm.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libpopt.so.0", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/libbeecrypt.so.7", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libselinux.so.1", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libbz2.so.1", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libz.so.1", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/liblzma.so.5", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libdb-4.7.so", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/libelf.so.1", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libpcre.so.3", O_RDONLY|O_CLOEXEC) = 3
statfs("/sys/fs/selinux", 0x7fff293b7710) = -1 ENOENT (No such file or directory)
statfs("/selinux", {f_type="EXT2_SUPER_MAGIC", f_bsize=4096, f_blocks=6264603, f_bfree=3584921, f_bavail=3260928, f_files=1602496, f_ffree=1283406, f_fsid={-826151455, -1443916296}, f_namelen=255, f_frsize=4096}) = 0
open("/proc/filesystems", O_RDONLY)     = 3
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/locale/ru_RU.utf8/LC_IDENTIFICATION", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib64/gconv/gconv-modules.cache", O_RDONLY) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_MEASUREMENT", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_TELEPHONE", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_ADDRESS", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_NAME", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_PAPER", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_MONETARY", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_COLLATE", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_TIME", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_NUMERIC", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/ru_RU.utf8/LC_CTYPE", O_RDONLY|O_CLOEXEC) = 3
stat("/var/lib/apt/.", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/etc/apt/apt.conf.d/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
openat(AT_FDCWD, "/etc/apt/apt.conf.d/", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 3
stat("/etc/apt/apt.conf.d/50-autoimports-cache-limit.conf", {st_mode=S_IFREG|0644, st_size=28, ...}) = 0
stat("/etc/apt/apt.conf.d/synaptic.conf", {st_mode=S_IFREG|0644, st_size=264, ...}) = 0
stat("/etc/apt/apt.conf.d/install-nvidia.conf", {st_mode=S_IFREG|0644, st_size=104, ...}) = 0
stat("/etc/apt/apt.conf.d/bad-comment.conf", {st_mode=S_IFREG|0644, st_size=539, ...}) = 0
open("/etc/apt/apt.conf.d/50-autoimports-cache-limit.conf", O_RDONLY) = 3
open("/etc/apt/apt.conf.d/bad-comment.conf", O_RDONLY) = 3