matchpathcon crashing in mock chroot

[Tom London]

On Wed, Sep 7, 2011 at 2:41 AM, Paul Howarth <paul at city-fan.org> wrote:
> I'm running matchpathcon as part of the libssh2 build to set the file
> context of a test script appropriately such that an instance of an
> openssh server that's run as part of the test suite transitions
> correctly to sshd_t. This has worked OK in the past but I'm now finding
> that on my F-15 builder matchpathcon is crashing when doing:
>
> /usr/sbin/matchpathcon -n /etc/rc.d/init.d/sshd
>
> gdb doesn't seem to be much help:
>
> [mockbuild at zion ~]$ /usr/sbin/matchpathcon -n /etc/rc.d/init.d/sshd
> Segmentation fault (core dumped)
> [mockbuild at zion ~]$ gdb /usr/sbin/matchpathcon
> GNU gdb (GDB) Fedora (7.3.50.20110722-6.fc16)
> Copyright (C) 2011 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
> and "show warranty" for details.
> This GDB was configured as "x86_64-redhat-linux-gnu".
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>...
> Reading symbols from /usr/sbin/matchpathcon...Reading symbols from /usr/lib/debug/sbin/matchpathcon.debug...done.
> done.
> (gdb) run  -n /etc/rc.d/init.d/sshd
> Starting program: /usr/sbin/matchpathcon -n /etc/rc.d/init.d/sshd
>
> Program received signal SIGSEGV, Segmentation fault.
> __strtok_r_1c (__nextp=read_sleb128: Corrupted DWARF expression.
> ) at /usr/include/bits/string2.h:1179
> 1179      while (*__s == __sep)
> (gdb) bt
> #0  __strtok_r_1c (__nextp=read_sleb128: Corrupted DWARF expression.
> ) at /usr/include/bits/string2.h:1179
> #1  init (rec=0x602010, opts=0x7ffff7ff3718, n=<optimized out>) at label_file.c:440
> #2  0x00007ffff7bc4b3d in selabel_open (backend=0, opts=0x7ffff7ff3718, nopts=5) at label.c:165
> #3  0x00007ffff7bc3e16 in matchpathcon_init_prefix_internal (path=0x0, subset=0x0) at matchpathcon.c:321
> #4  0x00007ffff7bc40a9 in matchpathcon (path=0x7fffffffe82a "/etc/rc.d/init.d/sshd", mode=0, con=0x7fffffffe418) at matchpathcon.c:406
> #5  0x0000000000400fe7 in printmatchpathcon (path=0x7fffffffe82a "/etc/rc.d/init.d/sshd", header=0, mode=<optimized out>) at matchpathcon.c:27
> #6  0x0000000000400d41 in main (argc=<optimized out>, argv=<optimized out>) at matchpathcon.c:156
> (gdb)
>
> I was getting an AVC earlier too, fixed by:
>
> allow setfiles_t sysfs_t:filesystem getattr;
>
> but fixing that didn't prevent the crash.
>
> This is with an F-15 host and Rawhide x86_64 target, libselinux-2.1.5-2.fc17.
>
> Any suggestions?
>
> Paul.
> --

Updating to libselinux-2.1.5-3.fc17.x86_64 fixes this segfault for me.


tom
-- 
Tom London