RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1269088 - ksh crashes under chroot environment with segmentation fault
Summary: ksh crashes under chroot environment with segmentation fault
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: ksh
Version: 7.2
Hardware: Unspecified
OS: Unspecified
urgent
medium
Target Milestone: rc
: ---
Assignee: Siteshwar Vashisht
QA Contact: Jan Kepler
URL:
Whiteboard:
Depends On:
Blocks: 1221766 1295396
TreeView+ depends on / blocked
 
Reported: 2015-10-06 09:39 UTC by Martin Kyral
Modified: 2017-08-01 16:26 UTC (History)
4 users (show)

Fixed In Version: ksh-20120801-34.el7
Doc Type: If docs needed, set a value
Doc Text:
Clone Of: 1221766
Environment:
Last Closed: 2017-08-01 16:26:55 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2017:1936 0 normal SHIPPED_LIVE ksh bug fix update 2017-08-01 17:55:48 UTC

Description Martin Kyral 2015-10-06 09:39:27 UTC 
This bug is present in RHEL 7, too.


Version-Release number of selected component (if applicable):

ksh-20120801-22.el7_1.2

+++ This bug was initially created as a clone of Bug #1221766 +++

Description of problem:

  ksh crashes under chroot environment with segmentation fault

Version-Release number of selected component (if applicable):

  ksh-20120801-21.el6.x86_64


How reproducible:

  Always

Steps to Reproduce:
1. Run the following commands.
  # cd /root
  # ./test.ksh
  # ulimit -c unlimited
  # chroot /root/NEWROOT /bin/ksh

Actual results:

  you will see
    Segmentation fault (core dumped)
  and get a corefile like "/root/NEWROOT/core.12345"

Expected results:

  Print an error.


Additional info:

(gdb) bt
#0  __strlen_sse42 () at ../sysdeps/x86_64/multiarch/strlen-sse4.S:32
#1  0x00000000004a7696 in strdup (s=0x0) at /usr/src/debug/ksh-20120801/src/lib/libast/string/strdup.c:59
#2  0x000000000041d447 in sh_histinit (sh_context=<value optimized out>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/edit/history.c:398
#3  0x0000000000406f2f in exfile (shp=0x76d180, iop=0x76adc0, fno=0) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/main.c:400
#4  0x0000000000407e60 in sh_main (ac=<value optimized out>, av=0x7fffc9f22c08, userinit=<value optimized out>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/main.c:353
#5  0x00007ff93162dd5d in __libc_start_main (main=0x406c00 <main>, argc=1, ubp_av=0x7fffc9f22c08, init=<value optimized out>, fini=<value optimized out>, 
    rtld_fini=<value optimized out>, stack_end=0x7fffc9f22bf8) at libc-start.c:226
#6  0x0000000000406b39 in _start ()

// strdup take '\0'.
(gdb) f 1
#1  0x00000000004a7696 in strdup (s=0x0) at /usr/src/debug/ksh-20120801/src/lib/libast/string/strdup.c:59
59		return (s && (t = oldof(0, char, n = strlen(s) + 1, 0))) ? (char*)memcpy(t, s, n) : (char*)0;

// ttyname(2) fails.
(gdb) f 2
#2  0x000000000041d447 in sh_histinit (sh_context=<value optimized out>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/edit/history.c:398
398					hp->tty = strdup(ttyname(2));



// strace shows ksh is trying to access /dev and /proc.
# strace -fttv chroot /root/NEWROOT /bin/ksh
...
14:46:55.268541 readlink("/proc/self/fd/2", 0x7f8e91325100, 4095) = -1 ENOENT (No such file or directory)
14:46:55.268558 fstat(2, {st_dev=makedev(0, 11), st_ino=3, st_mode=S_IFCHR|0620, st_nlink=1, st_uid=0, st_gid=5, st_blksize=1024, st_blocks=0, st_rdev=makedev(136, 0), st_atime=2015/05/14-14:46:55, st_mtime=2015/05/14-14:46:55, st_ctime=2015/05/14-14:40:13}) = 0
14:46:55.268583 stat("/dev/pts", 0x7ffff40874e0) = -1 ENOENT (No such file or directory)
14:46:55.268600 open("/dev", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
14:46:55.268620 --- SIGSEGV (Segmentation fault) @ 0 (0) ---
14:46:55.298019 +++ killed by SIGSEGV (core dumped) +++
Segmentation fault (core dumped)
Comment 1 Siteshwar Vashisht 2016-07-08 07:32:39 UTC 
There is no 'test.ksh' file attached with this issue. And I have not been able to reproduce this issue by executing 'chroot /root/NEWROOT /bin/ksh'. Please clarify the reproducer steps.
Comment 2 Martin Kyral 2016-07-11 07:49:48 UTC 
Sorry for the misleading filename. The reproducer is attached as 'reproducer' to the original bug, which is this bug a clone of: BZ#1221766 and it is included in the TCMS test case as test.sh: http://pkgs.devel.redhat.com/cgit/tests/ksh/tree/Regression/ksh-crashes-under-chroot-environment/test.sh
Comment 3 Siteshwar Vashisht 2016-07-11 11:09:05 UTC 
I have been able to reproduce this issue. Backtrace shows that strdup() is being called with NULL parameter :

0  __strlen_sse2_pminub () at ../sysdeps/x86_64/multiarch/strlen-sse2-pminub.S:38
#1  0x00000000004a64ae in strdup (s=0x0) at /usr/src/debug/ksh-20120801/src/lib/libast/string/strdup.c:59
#2  0x000000000041c76b in sh_histinit (sh_context=sh_context@entry=0x76e000 <sh>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/edit/history.c:398
#3  0x000000000040686f in exfile (shp=shp@entry=0x76e000 <sh>, iop=0x76bd20 <_Sfstdin>, fno=fno@entry=0) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/main.c:400
#4  0x000000000040795f in sh_main (ac=<optimized out>, av=0x7fffc4177d28, userinit=<optimized out>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/main.c:353
#5  0x00007f90d282eb15 in __libc_start_main (main=0x406640 <main>, argc=1, ubp_av=0x7fffc4177d28, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffc4177d18) at libc-start.c:274
#6  0x0000000000406671 in _start ()

It seems fd=2 is not attached to any terminal.

(gdb) frame 2
#2  0x000000000041c76b in sh_histinit (sh_context=sh_context@entry=0x76e000 <sh>) at /usr/src/debug/ksh-20120801/src/cmd/ksh93/edit/history.c:398
398                                     hp->tty = strdup(ttyname(2));
Comment 4 Siteshwar Vashisht 2016-07-14 06:17:22 UTC 
We already have patch for it https://bugzilla.redhat.com/attachment.cgi?id=1040916
Comment 9 errata-xmlrpc 2017-08-01 16:26:55 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2017:1936
Note You need to log in before you can comment on or make changes to this bug.