Segmentation fault (read) while loading map in CRenderTools::RenderEvalEnvelope, render_map.cpp:148

[mmmds]

The client crashes when an invalid map (12.map.zip) is loaded. Such a map can be delivered to the client by a malicious server.

Tested on Ubuntu 20.04 x86_64, Teeworlds version: f35da54b6f2c5f9fd4bbd4559f887ccf8f8cc526

Compilation with ASAN:

export CXXFLAGS="-ggdb -O0 -fsanitize=address -fno-omit-frame-pointer"
export CFLAGS="-ggdb -O0 -fsanitize=address -fno-omit-frame-pointer"
cmake ..
make

Run and connect to a server that delivers an invalid map:

./teeworlds "connect 127.0.0.1" "gfx_fullscreen 0" "gfx_screen_height 240" "gfx_screen_width 360"
[...]
AddressSanitizer:DEADLYSIGNAL
=================================================================
==33664==ERROR: AddressSanitizer: SEGV on unknown address 0x613858d99a28 (pc 0x5555558509b3 bp 0x7fffffffb0e0 sp 0x7fffffffae30 T0)
==33664==The signal is caused by a READ memory access.
    #0 0x5555558509b2 in CRenderTools::RenderEvalEnvelope(CEnvPoint*, int, int, float, float*) /home/osboxes/teeworlds/teeworlds-asan/src/game/client/render_map.cpp:148
    #1 0x5555556f5f50 in CMapLayers::EnvelopeEval(float, int, float*, void*) /home/osboxes/teeworlds/teeworlds-asan/src/game/client/components/maplayers.cpp:245
    #2 0x5555558532cf in CRenderTools::RenderQuads(CQuad*, int, int, void (*)(float, int, float*, void*), void*) /home/osboxes/teeworlds/teeworlds-asan/src/game/client/render_map.cpp:240
    #3 0x5555556f75f1 in CMapLayers::OnRender() /home/osboxes/teeworlds/teeworlds-asan/src/game/client/components/maplayers.cpp:375
    #4 0x555555827989 in CGameClient::OnRender() /home/osboxes/teeworlds/teeworlds-asan/src/game/client/gameclient.cpp:611
    #5 0x5555555fce4e in CClient::Render() /home/osboxes/teeworlds/teeworlds-asan/src/engine/client/client.cpp:796
    #6 0x5555555fce4e in CClient::Run() /home/osboxes/teeworlds/teeworlds-asan/src/engine/client/client.cpp:2131
    #7 0x5555555d24e5 in main /home/osboxes/teeworlds/teeworlds-asan/src/engine/client/client.cpp:2704
    #8 0x7ffff68e10b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
    #9 0x5555555dc48d in _start (/home/osboxes/teeworlds/teeworlds-asan/build/teeworlds+0x8848d)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /home/osboxes/teeworlds/teeworlds-asan/src/game/client/render_map.cpp:148 in CRenderTools::RenderEvalEnvelope(CEnvPoint*, int, int, float, float*)
==33664==ABORTING

Compilation without ASAN:

export CXXFLAGS="-ggdb -O0"
export CFLAGS="-ggdb -O0"
cmake ..
make

Run and connect to a server that delivers an invalid map:

./teeworlds "connect 127.0.0.1" "gfx_fullscreen 0" "gfx_screen_height 240" "gfx_screen_width 360"
[...]
Segmentation fault (core dumped)