Segfault in CVPCB

[Frank Severinsen]

Hi guys

When scrolling in CVPCB I have now experienced a crash 2 times.

I have the footprint viewer open and scrolled through a library.

When trying the second time through GDB I simply get:
Thread 1 "kicad" received signal SIGSEGV, Segmentation fault.
0x00007fff8f709285 in ?? () from /usr/bin/_cvpcb.kiface
(gdb) bt
#0 0x00007fff8f709285 in () at /usr/bin/_cvpcb.kiface

ofc, the second I closed the screen recorder I got the crash.

Application: kicad
Version: 5.1.2-f72e74a~84~ubuntu19.04.1, release build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.64.0 OpenSSL/1.1.1b zlib/1.2.11 libidn2/2.0.5 libpsl/0.20.2 (+libidn2/2.0.5) libssh/0.8.6/openssl/zlib nghttp2/1.36.0 librtmp/2.3
Platform: Linux 5.0.0-13-generic x86_64, 64 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 3.24
    Boost: 1.67.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.64.0
    Compiler: GCC 8.3.0 with C++ ABI 1013

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=ON
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=ON
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON

[Jon Evans (craftyjon)]

Hi Frank,
Do you use KiCad from the Ubuntu PPA?
If so, can you install the `kicad-dbg` package?
This will make the backtrace more useful.
Thanks

[Frank Severinsen (shack)]

Sure thing. Ill try it later

[Frank Severinsen (shack)]

@Jon
I hope this is more useful

Thread 1 "kicad" received signal SIGSEGV, Segmentation fault.
CVPCB_MAINFRAME::CreateScreenCmp (this=0x55555a1b59b0) at ./kicad/cvpcb/cvpcb_mainframe.cpp:819
819 ./kicad/cvpcb/cvpcb_mainframe.cpp: Ingen sådan fil eller filkatalog.
(gdb) bt
#0 0x00007fffbcef8285 in CVPCB_MAINFRAME::CreateScreenCmp() (this=0x55555a1b59b0) at ./kicad/cvpcb/cvpcb_mainframe.cpp:819
#1 0x00007fffbcef5a5f in FOOTPRINTS_LISTBOX::OnLeftClick(wxListEvent&) (event=..., this=0x55555c8d6c10) at ./kicad/cvpcb/footprints_listbox.cpp:218
#2 0x00007fffbcef5a5f in FOOTPRINTS_LISTBOX::OnLeftClick(wxListEvent&) (this=0x55555c8d6c10, event=...) at ./kicad/cvpcb/footprints_listbox.cpp:205
#3 0x00007ffff74f6a8e in wxEvtHandler::ProcessEventIfMatchesId(wxEventTableEntryBase const&, wxEvtHandler*, wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#4 0x00007ffff74f6b93 in wxEventHashTable::HandleEvent(wxEvent&, wxEvtHandler*) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#5 0x00007ffff74f6ecc in wxEvtHandler::TryHereOnly(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#6 0x00007ffff74f6f53 in wxEvtHandler::ProcessEventLocally(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#7 0x00007ffff74f6ff1 in wxEvtHandler::ProcessEvent(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#8 0x00007ffff7a94f6d in wxScrollHelperEvtHandler::ProcessEvent(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#9 0x00007ffff78b9680 in () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#10 0x00007ffff78baaef in () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#11 0x00007ffff78bc0dc in () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#12 0x00007ffff78bd98f in () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#13 0x00007ffff74f6a8e in wxEvtHandler::ProcessEventIfMatchesId(wxEventTableEntryBase const&, wxEvtHandler*, wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#14 0x00007ffff74f6b93 in wxEventHashTable::HandleEvent(wxEvent&, wxEvtHandler*) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#15 0x00007ffff74f6ecc in wxEvtHandler::TryHereOnly(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#16 0x00007ffff74f6f53 in wxEvtHandler::ProcessEventLocally(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#17 0x00007ffff74f6ff1 in wxEvtHandler::ProcessEvent(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#18 0x00007ffff74f6d97 in wxEvtHandler::SafelyProcessEvent(wxEvent&) () at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#19 0x00007ffff78a3b88 in () at /usr/lib/x86_64-linux-gnu/libwx_gtk3u_core-3.0.so.0
#20 0x00007ffff6a0544b in () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#21 0x00007ffff64f4e7d in g_closure_invoke () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#22 0x00007ffff6508535 in () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#23 0x00007ffff6510b5b in g_signal_emit_valist () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#24 0x00007ffff6511b2f in g_signal_emit () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#25 0x00007ffff69b21f4 in () at /usr/lib/x86_64-linux-gnu/libgtk-3...

[Frank Severinsen (shack)]

my steps to reproduce.

open kicad
open a schematic
open CVPCB
select "view selected footprint"
select one of the filtered footprints.
now press down arrow (as going through the list)
after a few it freezes/dies

[Jon Evans (craftyjon)]

@Jeff
Maybe 4020b568 is relevant here?

[Jeff Young (jeyjey)]

Could be a null pointer (ie: no object had focus)? Hopefully it's not a freed pointer or trashed memory...

[Frank Severinsen (shack)]

@Jeff please let me know if I can do anything to help

[Jeff Young (jeyjey)]

I can't reproduce this, but I've inserted some defensive code which may (or may not) fix it.

[Frank Severinsen (shack)]

Hi Jeff, where did insert the code? And can you also add it to 5.1 branch? (perhaps this should be milestoned for 5.1.3

[Jeff Young (jeyjey)]

commit 717b1d37bed647ef9dfe6258554ee5f51f999d6b
Author: Jeff Young <email address hidden>
Date: Fri May 10 19:59:44 2019 +0100

    Defensive coding that will possibly fix a crash when scrolling through footprints.

    Fixes: lp:1828289
    * https://bugs.launchpad.net/kicad/+bug/1828289

diff --git a/cvpcb/cvpcb_mainframe.cpp b/cvpcb/cvpcb_mainframe.cpp
index 19b480600..126c3e0fe 100644
--- a/cvpcb/cvpcb_mainframe.cpp
+++ b/cvpcb/cvpcb_mainframe.cpp
@@ -816,7 +816,8 @@ void CVPCB_MAINFRAME::CreateScreenCmp()
         fpframe->Raise(); // Make sure that is visible.
         Raise(); // .. but still we want the focus.

- focus->SetFocus();
+ if( focus )
+ focus->SetFocus();
     }

     fpframe->InitDisplay();

[Jeff Young (jeyjey)]

It's safe enough it should probably go into 5.1 whether it fixes the bug or not.

[Frank Severinsen (shack)]

Hi Jeff this seems to fix the issue, Thank you very much!