Hello John Comeau,
I just tried to reproduce this crash and could
get it just for a wheezy chroot:
warning: Can't read pathname for load map: Eingabe-/Ausgabefehler.
Core was generated by `/bin/bash -i'.
Program terminated with signal 11, Segmentation fault.
#0 0xff600400 in ?? ()
(gdb) bt
#0 0xff600400 in ?? ()
#1 0x7fbd6eacefed in time () at ../sysdeps/unix/sysv/linux/x86_64/time.S:36
#2 0x00420086 in main (argc=2, argv=0x7ffefa085978,
env=0x7ffefa085990) at ../bash/shell.c:450
In kernel log that access is also logged:
kernel: bash[472] vsyscall attempted with vsyscall=none ip:ff600400
cs:33 sp:7ffefa085818 ax:ff600400 si:7ffefa086f20 di:0
As far as I read this is a result of changing a special syscall
interface that got used for performance reasons
because of security concerns. (More details [1])
At least as far as I have tested, all Debian kernels after
Stretch release ( >= 4.10 ) behave that way, when using
a libc that relies on the old interface.
A workaround would be to boot linux with the kernel
parameter vsyscall=emulate.
Kind regards,
Bernhard
PS.: Was creating the same bug #907919 intentional or could that be closed?
[1] https://sysdig.com/blog/troubleshooting-containers/
apt install mc htop lz4 systemd-coredump gdb debootstrap
wget
http://192.168.178.25:/debian-9-stretch-deb.debian.org/pool/main/l/linux/linux-image-4.9.0-8-amd64_4.9.110-3+deb9u4_amd64.deb
dpkg -i linux-image-4.9.0-8-amd64_4.9.110-3+deb9u4_amd64.deb
wget
http://snapshot.debian.org/archive/debian/20170203T152214Z/pool/main/l/linux-signed/linux-image-4.10.0-rc6-amd64_4.10%7Erc6-1%7Eexp2_amd64.deb
dpkg -i linux-image-4.10.0-rc6-amd64_4.10~rc6-1~exp2_amd64.deb
wget
http://192.168.178.25:/debian-10-buster-deb.debian.org/pool/main/l/linux/linux-image-4.11.0-1-amd64_4.11.6-1_amd64.deb
dpkg -i linux-image-4.11.0-1-amd64_4.11.6-1_amd64.deb
debootstrap --arch=amd64 jessie /opt/jessie
http://192.168.178.25:/debian-8-jessie-deb.debian.org/
chroot /opt/jessie
# no crash
##
debootstrap --arch=amd64 wheezy /opt/wheezy
http://192.168.178.25:/debian-7-wheezy-deb.debian.org/
I: Installing core packages...
W: Failure trying to run: chroot "/opt/wheezy" dpkg --force-depends --install
/var/cache/apt/archives/base-passwd_3.5.26_amd64.deb
W: See /opt/wheezy/debootstrap/debootstrap.log for details
dmesg -w -T
[Mi Sep 12 15:44:57 2018] dpkg[21278] vsyscall attempted with vsyscall=none
ip:ff600400 cs:33 sp:7fff4d8e6588 ax:ff600400 si:428720
di:7fff4d8e65a0
[Mi Sep 12 15:44:57 2018] dpkg[21278]: segfault at ff600400 ip
ff600400 sp 7fff4d8e6588 error 15
[Mi Sep 12 15:44:57 2018] Code: Bad RIP value.
/opt/wheezy/debootstrap/debootstrap.log
2018-09-12 15:44:56
URL:http://192.168.178.25:/debian-7-wheezy-deb.debian.org/pool/main/z/zlib/zlib1g_1.2.7.dfsg-13_amd64.deb
[87392/87392] ->
"/opt/wheezy//var/cache/apt/archives/partial/zlib1g_1%3a1.2.7.dfsg-13_amd64.deb"
[1]
dpkg: warning: parsing file '/var/lib/dpkg/status' near line 5 package 'dpkg':
missing description
dpkg: warning: parsing file '/var/lib/dpkg/status' near line 5 package 'dpkg':
missing architecture
Segmentation fault (core dumped)
root@debian:~# chroot /opt/wheezy
Speicherzugriffsfehler (Speicherabzug geschrieben)
dmesg -w -T
[Mi Sep 12 15:47:39 2018] bash[21519] vsyscall attempted with vsyscall=none
ip:ff600400 cs:33 sp:7ffe4c83ef68 ax:ff600400 si:7ffe4c83ff20
di:0
[Mi Sep 12 15:47:39 2018] bash[21519]: segfault at ff600400 ip
ff600400 sp 7ffe4c83ef68 error 15
[Mi Sep 12 15:47:39 2018] Code: Bad RIP value.
##
reboot # into 4.9.0
rm /opt/wheezy -rf
debootstrap --arch=amd64 wheezy /opt/wheezy
http://192.168.178.25:/debian-7-wheezy-deb.debian.org/
mount -t proc proc /opt/wheezy/proc
chroot /opt/wheezy
# inside:
nano /etc/apt/sources.list
#deb-src http://192.168.178.25:/debian-7-wheezy-deb.debian.org wheezy
main
apt-get update
apt-get install gdb strace libc6-dbg
apt-get build-dep bash
dpkg-reconfigure locales
mkdir /root/libc6/orig -p
cd/root/libc6/orig
apt-get source libc6
mkdir /root/bash/orig -p
cd/root/bash/orig
apt-get source bash
cd ..
cp -a orig try1
cd try1/bash-4.2+dfsg/
DEB_BUILD_OPTIONS="noopt nostrip" dpkg-buildpackage -b
cd ..
dpkg -i bash_4.2+dfsg-0.1+deb7u3_amd64.deb
##
root@debian:~# uname -a
Linux debian 4.18.0-1-amd64 #1 SMP Debian 4.18.6-1 (2018-09-06) x86_64 GNU/Linux
root@debian:~# chroot /opt/wheezy /usr/bin/strace /bin/bash -i
execve("/bin/bash", ["/bin/bash", "-i"], [/* 11 vars */]) = 0
brk(0) = 0x1894000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) =
0x7efea8656000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
