git svn 2.26.0 segfault on fetch

Dear list,

When I use a "git svn fetch" on my git-SVN repository it dies with "error: git-svn died of signal 11".

I tried to get a coredump or attach GDB to it but as I see in strace there are signal handlers attached to INT, HUP, TERM, QUIT, and PIPE and possibly because of them no coredumps are generated even with unlimited "-c" and also possibly because of this GDB doesn't stop on SIGSEGV.

What I could do still with turned off ASLR is to run Valgrind with children tracking. It gave the following results:

Warning: invalid file descriptor -1 in syscall close()
Invalid read of size 4
   at 0x9B1A82C: UnknownInlinedFun (atomic_base.h:419)
   by 0x9B1A82C: UnknownInlinedFun (qatomic_cxx11.h:239)
   by 0x9B1A82C: UnknownInlinedFun (qbasicatomic.h:107)
   by 0x9B1A82C: UnknownInlinedFun (qrefcount.h:66)
   by 0x9B1A82C: UnknownInlinedFun (qstring.h:1263)
   by 0x9B1A82C: UnknownInlinedFun (kaboutdata.cpp:460)
   by 0x9B1A82C: KAboutData::~KAboutData() (kaboutdata.cpp:583)
   by 0x9B1AADC: (anonymous
namespace)::Q_QGS_s_registry::innerFunction()::Holder::~Holder()
(kaboutdata.cpp:1041)
   by 0x4A63706: __run_exit_handlers (exit.c:108)
   by 0x4A638BB: exit (exit.c:139)
   by 0x154465: main (perlmain.c:171)
 Address 0x80cf1c0 is not stack'd, malloc'd or (recently) free'd

Process terminating with default action of signal 11 (SIGSEGV): dumping core
 Access not within mapped region at address 0x80CF1C0
   at 0x9B1A82C: UnknownInlinedFun (atomic_base.h:419)
   by 0x9B1A82C: UnknownInlinedFun (qatomic_cxx11.h:239)
   by 0x9B1A82C: UnknownInlinedFun (qbasicatomic.h:107)
   by 0x9B1A82C: UnknownInlinedFun (qrefcount.h:66)
   by 0x9B1A82C: UnknownInlinedFun (qstring.h:1263)
   by 0x9B1A82C: UnknownInlinedFun (kaboutdata.cpp:460)
   by 0x9B1A82C: KAboutData::~KAboutData() (kaboutdata.cpp:583)
   by 0x9B1AADC: (anonymous
namespace)::Q_QGS_s_registry::innerFunction()::Holder::~Holder()
(kaboutdata.cpp:1041)
   by 0x4A63706: __run_exit_handlers (exit.c:108)
   by 0x4A638BB: exit (exit.c:139)
   by 0x154465: main (perlmain.c:171)
 If you believe this happened as a result of a stack
 overflow in your program's main thread (unlikely but
 possible), you can try to increase the size of the
 main thread stack using the --main-stacksize= flag.
 The main thread stack size used in this run was 8388608.

During stracing I found this line around the SIGSEGV: close(-1) = -1 EBADF

If you could tell me how it's possible to attach GDB onto it, I'd be glad to provide you some backtraces as well.

Version: 2.26.0.

All the best,

Ákos

On 2020-03-27 at 16:36:56, Szőts Ákos wrote:

Git uses the Subversion Perl bindings and git-svn is written entirely in Perl. While it's possible we've broken something, it's probably a little more likely that the Subversion Perl bindings on your system are a little broken and that's what's causing the issue.

What operating system are you using?

This looks like you're loading something with Qt. Are you using the Subversion KWallet integration? Does disabling it make things work?

You'd need to run something like the following:

  gdb --args /usr/bin/perl /usr/lib/git-core/git-svn <ARGS>

Note that I don't use git-svn and remember next to nothing about using Subversion, so hopefully any information you provide makes sense to someone more familiar with git-svn than I.