Re: RH 7 nfs-utils update causes segfault

[Mark Valites <mvalites@buffalo.edu>]

On 03/08/2016 01:21 PM, Benjamin Coddington wrote:

> That's weird -- you're getting SIG37 - I don't know what that could be.  Can
> you just do another 'continue' there?  If not, can you do 'ptype $_siginfo'
> there?

Here's a new gdb session:

GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-80.el7
Copyright (C) 2013 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.
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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/>.
Attaching to process 464
Reading symbols from /usr/sbin/rpc.gssd...Reading symbols from 
/usr/lib/debug/usr/sbin/rpc.gssd.debug...done.
done.
Reading symbols from /lib64/libtirpc.so.1...Reading symbols from 
/lib64/libtirpc.so.1...(no debugging symbols found)...done.
(no debugging symbols found)...done.
Loaded symbols for /lib64/libtirpc.so.1
Reading symbols from /lib64/libgssapi_krb5.so.2...Reading symbols from 
/usr/lib/debug/usr/lib64/libgssapi_krb5.so.2.2.debug...done.
done.
Loaded symbols for /lib64/libgssapi_krb5.so.2
Reading symbols from /lib64/libkrb5.so.3...Reading symbols from 
/usr/lib/debug/usr/lib64/libkrb5.so.3.3.debug...done.
done.
Loaded symbols for /lib64/libkrb5.so.3
Reading symbols from /lib64/libk5crypto.so.3...Reading symbols from 
/usr/lib/debug/usr/lib64/libk5crypto.so.3.1.debug...done.
done.
Loaded symbols for /lib64/libk5crypto.so.3
Reading symbols from /lib64/libcom_err.so.2...Reading symbols from 
/usr/lib/debug/usr/lib64/libcom_err.so.2.1.debug...done.
done.
Loaded symbols for /lib64/libcom_err.so.2
Reading symbols from /lib64/libc.so.6...Reading symbols from 
/usr/lib/debug/usr/lib64/libc-2.17.so.debug...done.
done.
Loaded symbols for /lib64/libc.so.6
Reading symbols from /lib64/libnsl.so.1...Reading symbols from 
/usr/lib/debug/usr/lib64/libnsl-2.17.so.debug...done.
done.
Loaded symbols for /lib64/libnsl.so.1
Reading symbols from /lib64/libpthread.so.0...Reading symbols from 
/usr/lib/debug/usr/lib64/libpthread-2.17.so.debug...done.
done.
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Loaded symbols for /lib64/libpthread.so.0
Reading symbols from /lib64/libkrb5support.so.0...Reading symbols from 
/usr/lib/debug/usr/lib64/libkrb5support.so.0.1.debug...done.
done.
Loaded symbols for /lib64/libkrb5support.so.0
Reading symbols from /lib64/libdl.so.2...Reading symbols from 
/usr/lib/debug/usr/lib64/libdl-2.17.so.debug...done.
done.
Loaded symbols for /lib64/libdl.so.2
Reading symbols from /lib64/libkeyutils.so.1...Reading symbols from 
/usr/lib/debug/usr/lib64/libkeyutils.so.1.5.debug...done.
done.
Loaded symbols for /lib64/libkeyutils.so.1
Reading symbols from /lib64/libresolv.so.2...Reading symbols from 
/usr/lib/debug/usr/lib64/libresolv-2.17.so.debug...done.
done.
Loaded symbols for /lib64/libresolv.so.2
Reading symbols from /lib64/ld-linux-x86-64.so.2...Reading symbols from 
/usr/lib/debug/usr/lib64/ld-2.17.so.debug...done.
done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2
Reading symbols from /lib64/libselinux.so.1...Reading symbols from 
/usr/lib/debug/usr/lib64/libselinux.so.1.debug...done.
done.
Loaded symbols for /lib64/libselinux.so.1
Reading symbols from /lib64/libpcre.so.1...Reading symbols from 
/lib64/libpcre.so.1...(no debugging symbols found)...done.
(no debugging symbols found)...done.
Loaded symbols for /lib64/libpcre.so.1
Reading symbols from /lib64/liblzma.so.5...Reading symbols from 
/lib64/liblzma.so.5...(no debugging symbols found)...done.
(no debugging symbols found)...done.
Loaded symbols for /lib64/liblzma.so.5
Reading symbols from /usr/lib64/gssproxy/proxymech.so...Reading symbols 
from /usr/lib/debug/usr/lib64/gssproxy/proxymech.so.debug...done.
done.
Loaded symbols for /usr/lib64/gssproxy/proxymech.so
Reading symbols from /lib64/libgssrpc.so.4...Reading symbols from 
/usr/lib/debug/usr/lib64/libgssrpc.so.4.2.debug...done.
done.
Loaded symbols for /lib64/libgssrpc.so.4
0x00007f4c7041fbe9 in __GI_ppoll (fds=fds@entry=0x7f4c72c45b50, 
nfds=nfds@entry=1024, timeout=<optimized out>, timeout@entry=0x0, 
sigmask=sigmask@entry=0x7ffd00c8b7d0)
     at ../sysdeps/unix/sysv/linux/ppoll.c:51
51          result = INLINE_SYSCALL (ppoll, 5, fds, nfds, timeout, 
sigmask, _NSIG / 8);
Missing separate debuginfos, use: debuginfo-install 
libtirpc-0.2.4-0.6.el7.x86_64 pcre-8.32-15.el7.x86_64 
xz-libs-5.1.2-12alpha.el7.x86_64
(gdb) continue
Continuing.

Program received signal SIG37, Real-time event 37.
0x00007f4c7041fbe9 in __GI_ppoll (fds=fds@entry=0x7f4c72c45b50, 
nfds=nfds@entry=1024, timeout=<optimized out>, timeout@entry=0x0, 
sigmask=sigmask@entry=0x7ffd00c8b7d0)
     at ../sysdeps/unix/sysv/linux/ppoll.c:51
51          result = INLINE_SYSCALL (ppoll, 5, fds, nfds, timeout, 
sigmask, _NSIG / 8);
(gdb) bt
#0  0x00007f4c7041fbe9 in __GI_ppoll (fds=fds@entry=0x7f4c72c45b50, 
nfds=nfds@entry=1024, timeout=<optimized out>, timeout@entry=0x0, 
sigmask=sigmask@entry=0x7ffd00c8b7d0)
     at ../sysdeps/unix/sysv/linux/ppoll.c:51
#1  0x00007f4c714ab587 in ppoll (__ss=0x7ffd00c8b7d0, __timeout=0x0, 
__nfds=1024, __fds=0x7f4c72c45b50) at /usr/include/bits/poll2.h:77
#2  gssd_poll (nfds=1024, fds=0x7f4c72c45b50) at gssd_main_loop.c:194
#3  gssd_run () at gssd_main_loop.c:258
#4  0x00007f4c714aa11a in main (argc=<optimized out>, 
argv=0x7ffd00c8ba38) at gssd.c:216
(gdb) continue
Continuing.

Program received signal SIG37, Real-time event 37.
0x00007f4c7041fbe9 in __GI_ppoll (fds=fds@entry=0x7f4c72c45b50, 
nfds=nfds@entry=1024, timeout=<optimized out>, timeout@entry=0x0, 
sigmask=sigmask@entry=0x7ffd00c8b7d0)
     at ../sysdeps/unix/sysv/linux/ppoll.c:51
51          result = INLINE_SYSCALL (ppoll, 5, fds, nfds, timeout, 
sigmask, _NSIG / 8);
(gdb) ptype $_siginfo
type = struct {
     int si_signo;
     int si_errno;
     int si_code;
     union {
         int _pad __attribute__ ((vector_size(28)));
         struct {...} _kill;
         struct {...} _timer;
         struct {...} _rt;
         struct {...} _sigchld;
         struct {...} _sigfault;
         struct {...} _sigpoll;
     } _sifields;
}


In order to keep the gssd process alive (to be able to attach gbd to 
it), I've commented out my nfs mounts in vfstab & am then mounting the 
export manually:

$ sudo mount /my/mountpoint
Error getting authority: Error initializing authority: Error calling 
StartServiceByName for org.freedesktop.PolicyKit1: Timeout was reached 
(g-io-error-quark, 24)
Failed to start rpc-statd.service: Connection timed out
mount.nfs: access denied by server while mounting nfsserver:/the_export

$ systemctl --failed
   UNIT           LOAD   ACTIVE SUB    DESCRIPTION
  polkit.service loaded failed failed Authorization Manager


I see now that when mounting manually this way, the gss daemon actually 
doesn't die. The rpc-statd process the mount whines about failing to 
start *is* running.

-Mark