CMapLayers::OnRender client crash

[ChillerDragon]

I currently mess with re-implementing the server. And it is full of bugs. One of those causes the client to crash.

I can reproduce consistently so if someone needs more info let me know either here or on irc.

[2022-11-13 08:12:59][client]: connecting to '127.0.0.1:8303'
[2022-11-13 08:12:59][connection]: got token, replying, token=5b6c576 mytoken=2d75a94a
[2022-11-13 08:12:59][client]: connected, sending info

Thread 1 "teeworlds" received signal SIGSEGV, Segmentation fault.
0x00005555555c3aa9 in CMapLayers::OnRender (this=0x55555586e680 <gs_MapLayersBackGround>)
    at /home/chiller/Desktop/git/teeworlds/src/game/client/components/maplayers.cpp:273
273                     if(!Config()->m_GfxNoclip && pGroup->m_Version >= 2 && pGroup->m_UseClipping)
(gdb) bt
#0  0x00005555555c3aa9 in CMapLayers::OnRender (this=0x55555586e680 <gs_MapLayersBackGround>) at /home/chiller/Desktop/git/teeworlds/src/game/client/components/maplayers.cpp:273
#1  0x0000555555622e89 in CGameClient::OnRender (this=0x55555593f950) at /home/chiller/Desktop/git/teeworlds/src/game/client/gameclient.cpp:614
#2  0x0000555555570e25 in CClient::Render (this=0x7ffff706f010) at /home/chiller/Desktop/git/teeworlds/src/engine/client/client.cpp:797
#3  0x0000555555576a76 in CClient::Run (this=0x7ffff706f010) at /home/chiller/Desktop/git/teeworlds/src/engine/client/client.cpp:2133
#4  0x0000555555578c67 in main (argc=2, argv=0x7fffffffca58) at /home/chiller/Desktop/git/teeworlds/src/engine/client/client.cpp:2710
(gdb) print pGroup 
$1 = (CMapItemGroup *) 0x0

[ChillerDragon]

I hotfixed it for me using

CMapItemGroup *pGroup = pLayers->GetGroup(g);
if(!pGroup)
  continue;

In here

teeworlds/src/game/client/components/maplayers.cpp

Line 271 in 26d24ec

CMapItemGroup *pGroup = pLayers->GetGroup(g);