Bug 525822 – net-dialup/ppp-2.4.7 USE=dhcp segmentation fault in ? at ?

• Product: Gentoo Linux
• Status: RESOLVED NEEDINFO

[Description Alex Glazunov 2014-10-18 23:14:15 UTC]

I have PPTP server running net-dialup/pptpd-1.4.0 with net-dialup/ppp-2.4.5-r3
My configuration:

/etc/pptpd.conf:
listen <IP>
option /etc/ppp/options.pptpd
logwtmp
delegate

/etc/ppp/options.pptp:
lock
auth
refuse-pap
refuse-eap
refuse-chap
refuse-mschap
require-mschap-v2
require-mppe-128
name office
proxyarp
mtu 1400
mru 1400

netmask 255.255.254.0
ms-dns <first-dns-ip>
ms-dns <second-dns-ip>

plugin dhcpc.so
dhcp-interface net0
dhcp-server <dhcp-server-ip>
<server-ip>:

After upgrade to net-dialup/ppp-2.4.7 PPTP does not work:

dmesg:
pppd[2955]: segfault at 7f9924000000 ip 00007f9928519884 sp 00007fffd3889f88 error 4 in libc-2.19.so[7f9928497000+19e000]

Disabling dhcp plugin solves the problem as well as downgrade to previous ppp version: net-dialup/ppp-2.4.6-r3

This is complete PPTP session log:
Oct 19 03:02:52 host pptpd[2814]: CTRL: Client XXX.XXX.XXX.XXX control connection started
Oct 19 03:02:53 host pptpd[2814]: CTRL: Starting call (launching pppd, opening GRE)
Oct 19 03:02:53 host pppd[2815]: Plugin dhcpc.so loaded.
Oct 19 03:02:53 host pppd[2815]: DHCPC: plugin initialized
Oct 19 03:02:53 host pptpd[2814]: GRE: read(fd=6,buffer=6075c0,len=8196) from PTY failed: status = -1 error = Input/output error, usually caused by unexpected termination of pppd, check option syntax and pppd logs
Oct 19 03:02:53 host pptpd[2814]: CTRL: PTY read or GRE write failed (pty,gre)=(6,7)
Oct 19 03:02:53 host pptpd[2814]: CTRL: Reaping child PPP[2815]
Oct 19 03:02:53 host kernel: [ 6378.582678] pppd[2815]: segfault at 7f4bc0000000 ip 00007f4bc2f83884 sp 00007fff69e9a758 error 4 in libc-2.19.so[7f4bc2f01000+19e000]
Oct 19 03:02:53 host pptpd[2814]: CTRL: Client XXX.XXX.XXX.XXX control connection finished

[Comment 1 Jeroen Roovers (RETIRED) 2014-10-19 07:46:34 UTC]

1) Please post your `emerge --info net-dialup/ppp' output in a comment.
2) Please attach the gdb backtrace output of pppd segfaulting.

[Comment 2 Alex Glazunov 2014-10-19 19:07:22 UTC]

Portage 2.2.8-r2 (default/linux/amd64/13.0, gcc-4.7.3, glibc-2.19-r1, 3.12.13-gentoo x86_64)
=================================================================
                         System Settings
=================================================================
System uname: Linux-3.12.13-gentoo-x86_64-Intel-R-_Celeron-R-_D_CPU_3.20GHz-with-gentoo-2.2
KiB Mem:     1015848 total,    260284 free
KiB Swap:    4194236 total,   4194236 free
Timestamp of tree: Sat, 18 Oct 2014 08:15:01 +0000
ld GNU ld (GNU Binutils) 2.23.2
app-shells/bash:          4.2_p53
dev-lang/perl:            5.18.2-r2
dev-lang/python:          2.7.7, 3.3.5-r1, 3.4.1
dev-util/pkgconfig:       0.28-r1
sys-apps/baselayout:      2.2
sys-apps/openrc:          0.12.4
sys-apps/sandbox:         2.6-r1
sys-devel/autoconf:       2.69
sys-devel/automake:       1.13.4
sys-devel/binutils:       2.23.2
sys-devel/gcc:            4.7.3-r1
sys-devel/gcc-config:     1.7.3
sys-devel/libtool:        2.4.2-r1
sys-devel/make:           4.0-r1
sys-kernel/linux-headers: 3.13 (virtual/os-headers)
sys-libs/glibc:           2.19-r1
Repositories: gentoo
ACCEPT_KEYWORDS="amd64"
ACCEPT_LICENSE="* -@EULA"
CBUILD="x86_64-pc-linux-gnu"
CFLAGS="-O2 -pipe"
CHOST="x86_64-pc-linux-gnu"
CONFIG_PROTECT="/etc"
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo"
CXXFLAGS="-O2 -pipe"
DISTDIR="/usr/portage/distfiles"
FCFLAGS="-O2 -pipe"
FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync"
FFLAGS="-O2 -pipe"
GENTOO_MIRRORS="http://gentoo.bloodhost.ru/ http://mirror2.corbina.ru/gentoo-distfiles/ http://mirror.yandex.ru/gentoo-distfiles/"
LANG="en_US.UTF8"
LC_ALL="en_US.UTF8"
LDFLAGS="-Wl,-O1 -Wl,--as-needed"
PKGDIR="/usr/portage/packages"
PORTAGE_CONFIGROOT="/"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY=""
SYNC="rsync://rsync2.ru.gentoo.org/gentoo-portage"
USE="acl amd64 berkdb bindist bzip2 cli cracklib crypt cxx dri fortran gdbm iconv mmx modules multilib ncurses nls nptl openmp pam pcre readline session sse sse2 ssl tcpd unicode zlib" ABI_X86="64" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-5" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_3" RUBY_TARGETS="ruby19 ruby20" USERLAND="GNU" VIDEO_CARDS="fbdev glint intel mach64 mga nouveau nv r128 radeon savage sis tdfx trident vesa via vmware dummy v4l" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account"
Unset:  CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, MAKEOPTS, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON

=================================================================
                        Package Settings
=================================================================

net-dialup/ppp-2.4.6-r3 was built with the following:
USE="dhcp pam -activefilter -atm -eap-tls -gtk -ipv6 -radius" ABI_X86="64"

[Comment 3 Alex Glazunov 2014-10-19 19:10:16 UTC]

Unfortunately I can't do backtraces on a production server.

[Comment 4 Jeroen Roovers (RETIRED) 2014-10-19 19:34:28 UTC]

Then you should learn what a "staging server" is I guess. Please reopen this bug report when you do have a proper backtrace.

[Comment 5 Alex Glazunov 2014-10-20 11:08:03 UTC]

It seems I should learn C++ too...