threads / discuss / 34396

segmentation fault after successful completion of certain git svn commands

Subject: segmentation fault after successful completion of certain git svn commands

## tl;dr

One message between Jul 10, 2013 and Jul 10, 2013.

replies: 0people: 1as markdown or json

Friedrich Delgado· Jul 10, 2013, 10:51 UTC · lore
Hi!

I suspect I may have found a problem in the way git-svn uses SVN::Core that leads to a segmentation fault. That's a hypothesis based on the following incomplete findings:

git version 1.8.3.2.50.g531c8dd (from recent git maint) svn, version 1.7.10 (r1485443) (from openSUSE 12.2) subversion-perl-1.7.10-4.16.1.x86_64 (from openSUSE 12.2)

,----[ ~/.subversion/config ]
  [auth]
  password-stores = kwallet
  store-passwords = yes
  store-ssl-client-cert-pp = yes
`----

~/.subversion/servers is set up to use a pkcs12 certificate for certain projects.

Unfortunately I'm not the administrator of the box, so I'd have to ask the system administrator to install the debug packages for me if you need a useful gdb backtrace. Maybe the following information helps, if not, I'll see what I can do to provide a meaningful gdb backtrace.

In a git-svn checkout of such a project:
,----[ redacted ]
  > perl -d:Trace ~/anon-vc/git/git-svn rebase 2>&1|tail
  >> /usr/lib/perl5/5.16.0/File/Temp.pm:895:                   @{ $dirs_to_unlink{$$} } : () );
  >> /usr/lib/perl5/5.16.0/File/Temp.pm:896:       foreach my $dir (@dirs) {
  >> /usr/lib/perl5/5.16.0/File/Temp.pm:908:       @{ $files_to_unlink{$$} } = ()
  >> /usr/lib/perl5/5.16.0/File/Temp.pm:910:       @{ $dirs_to_unlink{$$} } = ()
  >> /home/user/local/stow/git/lib/perl5/site_perl/5.16.0/Git/SVN.pm:1659:     unmemoize_svn_mergeinfo_functions();
  >> /home/user/local/stow/git/lib/perl5/site_perl/5.16.0/Git/SVN.pm:1626:             return if not $memoized;
  >> /home/user/local/stow/git/lib/perl5/site_perl/5.16.0/Git/SVN.pm:85:       unlink keys %LOCKFILES if %LOCKFILES;
  >> /home/user/local/stow/git/lib/perl5/site_perl/5.16.0/Git/SVN.pm:86:       unlink keys %INDEX_FILES if %INDEX_FILES;
  >> /usr/lib/perl5/vendor_perl/5.16.0/x86_64-linux-thread-multi/SVN/Core.pm:390:     $globaldestroy = 1;
  >> /usr/lib/perl5/vendor_perl/5.16.0/x86_64-linux-thread-multi/SVN/Core.pm:58:     SVN::_Core::apr_terminate();
  [1]    1631 segmentation fault (core dumped)  perl -d:Trace ~/anon-vc/git/git-svn rebase 2>&1 | 
         1632 done                              tail
`----
(The segfault will also occur after git svn clone.)

It appears that rebase and clone lead to correct results. An strace seems to indicate that the segfault occurs after a munmap.

,----[ redacted ]
  > strace -f git svn rebase 2>&1|tail -20
  [pid  2355] rt_sigaction(SIGRT_32, NULL, {SIG_DFL, [], 0}, 8) = 0
  [pid  2355] rt_sigaction(SIGABRT, NULL, {SIG_DFL, [], 0}, 8) = 0
  [pid  2355] rt_sigaction(SIGCHLD, NULL, {0x7ff0c737d250, [], SA_RESTORER|SA_NOCLDSTOP, 0x7ff0d00a1140}, 8) = 0
  [pid  2355] rt_sigaction(SIGIO, NULL, {SIG_DFL, [], 0}, 8) = 0
  [pid  2355] rt_sigaction(SIGSYS, NULL, {SIG_DFL, [], 0}, 8) = 0
  [pid  2355] futex(0x7ff0ca0372c0, FUTEX_WAKE_PRIVATE, 2147483647) = 0
  [pid  2355] futex(0x7ff0ca037280, FUTEX_WAKE_PRIVATE, 2147483647) = 0
  [pid  2355] futex(0x7ff0cab9a0a0, FUTEX_WAKE_PRIVATE, 2147483647) = 0
  [pid  2355] write(6, "XXXIXTAMPEREDXWITHXTHISXSTRINGXXXXXXX"..., 37) = 37
  [pid  2355] brk(0x30f7000)              = 0x30f7000
  [pid  2355] close(6)                    = 0
  [pid  2355] munmap(0x7ff0c7940000, 2113920) = 0
  [pid  2355] --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x7ff0c7941df0} ---
  [pid  2355] +++ killed by SIGSEGV (core dumped) +++
  <... wait4 resumed> [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV && WCOREDUMP(s)}], 0, NULL) = 2355
  --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_DUMPED, si_pid=2355, si_status=SIGSEGV, si_utime=22, si_stime=95} ---
  write(2, "error: git-svn died of signal 11"..., 33error: git-svn died of signal 11
  ) = 33
  exit_group(139)                         = ?
  +++ exited with 139 +++
`----
(both traces were edited a bit by me)
Maybe the following two urls I found are related or helpful:

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=551769 http://subversion.tigris.org/ds/viewMessage.do?dsForumId=1065&dsMessageId=2356032

That's all I can think of right now. Please tell me if there's any more information I should provide to help you narrow this down.

Thanks in advance and kind regards
       Friedrich Delgado
-- 
Dipl.-Inform Friedrich Delgado             (Projekt- und Entwicklungsteam)

DFN-CERT Services GmbH, https://www.dfn-cert.de/
Sitz/Register: Hamburg,  AG Hamburg,  HRB 88805,  Ust-IdNr.: DE 232129737
Sachsenstraße 5, 20097 Hamburg/Germany,  CEO: Dr. Klaus-Peter Kossakowski

← back to recent threads