[BUG]: Sven Co-op 5.26 Linux dedicated server occasionally segfaults on map change #91
Description
👉👈 Contact Details (optional)
No response
🤔 What happened?
svends occasionally segfaults on map change. Coredump from a debug build shows a null pointer:
Core was generated by `./svends_i686 -game svencoop -strictportbind +ip 94.XX.XX.XX -port 27015 +clientport 27005 +map svencoop1 +servercfgfile svenserver.cfg +maxplayers 16 -insecure -debug +sv_cheats 2 -pidfile svends.4051776.pid'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0xdfdd774b in meta_collect_fix_data (esp=0xf727c3c0, data=...) at /src/Metamod-R/metamod/src/metamod.cpp:461
461 do pret--;
(gdb) bt 6
#0 0xdfdd774b in meta_collect_fix_data (esp=0xf727c3c0, data=std::vector of length 1, capacity 1 = {...}) at /src/Metamod-R/metamod/src/metamod.cpp:461
#1 0xdfdd780d in meta_collect_fix_data (esp=0xfffdc688, data=std::vector of length 1, capacity 1 = {...}) at /src/Metamod-R/metamod/src/metamod.cpp:500
#2 0xdfdd78a2 in meta_rebuild_callbacks () at /src/Metamod-R/metamod/src/metamod.cpp:532
#3 0xdfdd8e1f in MPluginList::refresh (this=0x57063fa0, now=PT_CHANGELEVEL) at /src/Metamod-R/metamod/src/mlist.cpp:563
#4 0xdfdd458a in mm_ServerDeactivate () at /src/Metamod-R/metamod/src/dllapi.cpp:61
#5 0xf61e0792 in ?? () from /home/gameservers/Games/steam/svencoop/serverfiles/engine_i686.so
(gdb) x pret
0xe3240000: 0x00000000
For debugging, I'm using my own build of metamod, which is rehlds/Metamod-R@1.3.0.149 with only this change:
diff --git a/metamod/CMakeLists.txt b/metamod/CMakeLists.txt
index 18d46fc..b82d26e 100644
--- a/metamod/CMakeLists.txt
+++ b/metamod/CMakeLists.txt
@@ -38 +38 @@ set(COMPILE_FLAGS "-m32 -U_FORTIFY_SOURCE")
-set(LINK_FLAGS "-m32 -s")
+set(LINK_FLAGS "-m32")And built using:
./build.sh -c=gcc -j=$(nproc) -DDEBUG=ON -DCMAKE_BUILD_TYPE=COMPAT_GLIBC⚠️ Meta-information
OS: Debian 13.3 (amd64)
Engine and metamod version info:
version; game version; meta version; meta list
Protocol version 48
Engine version 5.0.1.8 (svencoop)
Engine build: 19:37:07 Dec 5 2024 (10269)
Metamod-r v1.3.0.149+m, API (5:13)
Metamod-r build: 00:33:54 Jan 26 2026
Metamod-r from: https://github.com/rehlds/Metamod-R/commit/603a257
Currently loaded plugins:
description stat pend file vers src load unload
[ 1] AMX Mod X RUN - amxmodx_mm_i386.so v1.10.0.5474 ini Start ANY
1 plugins, 1 running
AMXX version info:
amxx version; amxx plugins
AMX Mod X 1.10.0.5474 (http://www.amxmodx.org)
Authors:
David "BAILOPAN" Anderson, Pavol "PM OnoTo" Marko
Felix "SniperBeamer" Geyer, Jonny "Got His Gun" Bergstrom
Lukasz "SidLuke" Wlasinski, Christian "Basic-Master" Hammacher
Borja "faluco" Ferrer, Scott "DS" Ehlert
Compiled: Dec 1 2025 07:49:57
Built from: https://github.com/alliedmodders/amxmodx/commit/0c31b61
Build ID: 5474:0c31b61
Core mode: JIT+ASM32
Currently loaded plugins:
id name version author url file status
[ 1] 0 Admin Base 1.10.0.547 AMXX Dev Team admin.amxx running
[ 2] 1 Admin Commands 1.10.0.547 AMXX Dev Team admincmd.am running
[ 3] 2 Admin Help 1.10.0.547 AMXX Dev Team adminhelp.a running
[ 4] 3 Slots Reservation 1.10.0.547 AMXX Dev Team adminslots. running
[ 5] 4 Multi-Lingual System 1.10.0.547 AMXX Dev Team multilingua running
[ 6] 5 Menus Front-End 1.10.0.547 AMXX Dev Team menufront.a running
[ 7] 6 Commands Menu 1.10.0.547 AMXX Dev Team cmdmenu.amx running
[ 8] 7 Players Menu 1.10.0.547 AMXX Dev Team plmenu.amxx running
[ 9] 8 Maps Menu 1.10.0.547 AMXX Dev Team mapsmenu.am running
[ 10] 9 Plugin Menu 1.10.0.547 AMXX Dev Team pluginmenu. running
[ 11] 10 Admin Chat 1.10.0.547 AMXX Dev Team adminchat.a running
[ 12] 11 Anti Flood 1.10.0.547 AMXX Dev Team antiflood.a running
[ 13] 12 Admin Votes 1.10.0.547 AMXX Dev Team adminvote.a running
[ 14] 13 NextMap 1.10.0.547 AMXX Dev Team nextmap.amx running
[ 15] 14 Nextmap Chooser 1.10.0.547 AMXX Dev Team mapchooser. running
[ 16] 15 TimeLeft 1.10.0.547 AMXX Dev Team timeleft.am running
[ 17] 16 Pause Plugins 1.10.0.547 AMXX Dev Team pausecfg.am running
[ 18] 17 Stats Configuration 1.10.0.547 AMXX Dev Team statscfg.am running
18 plugins, 18 running📄 Relevant log output
L 26/01/2026 - 14:42:10: Changing to level "afrikakorps1".
L 26/01/2026 - 14:42:10: [META] ini: Begin re-reading plugins list: /home/gameservers/Games/steam/svencoop/serverfiles/svencoop/addons/metamod/plugins.ini
L 26/01/2026 - 14:42:10: [META] ini: Read plugin config for: AMX Mod X
L 26/01/2026 - 14:42:10: [META] ini: Finished reading plugins list: /home/gameservers/Games/steam/svencoop/serverfiles/svencoop/addons/metamod/plugins.ini; Found 1 plugins
L 26/01/2026 - 14:42:10: [META] dll: Updating plugins...
L 26/01/2026 - 14:42:10: [META] (debug:1) Keeping plugin 'AMX Mod X'
L 26/01/2026 - 14:42:10: [META] dll: Finished updating 1 plugins; kept 1, loaded 0, unloaded 0, reloaded 0, delayed 0
L 26/01/2026 - 14:42:10: [META] dll: Begin scan to collect callback fix data...
./svends_run: line 440: 4051805 Segmentation fault (core dumped) $GAME_BIN_CMD
Uh oh it seems the server has crashed or failed to run (╯°□°）╯︵ ┻━┻
Support available on our Discord server: https://discord.gg/svencoop
Mon 26 Jan 14:42:12 GMT 2026: Server restart in 10 seconds