Add syscall overflow detection to prevent VM infinite loops#371
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The stock id 1.32 qagame.qvm has a bug in ClientSpawn() where a do/while(1) loop retrying spawn point selection can loop forever if all spawn points would telefrag and the fallback has FL_NO_BOTS set, causing the server to hang at 100% CPU. Since Quake3e is engine-only and ships no QVMs, add a general-purpose syscall counter that resets at each top-level VM_Call() and errors out after 1,000,000 syscalls, consistent with existing vm_rtChecks safety infrastructure. Fixes ec-#370
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Summary
VM_Call()syscall counter that detects infinite loops in QVM code, preventing the server from hanging at 100% CPUVM_Call()invocation and triggersCom_Error(ERR_DROP, ...)after 1,000,000 syscallsvm_rtChecksinfrastructureMotivation
The stock id Software 1.32
qagame.qvm(frompak8.pk3) has an infinite loop bug inClientSpawn()that causes the server to hang when all spawn points would telefrag (reproducible with 8+ bots on small maps likecpm30_b1). ioquake3 fixed this in the game code (commit f5d79ea), but since Quake3e is engine-only and ships no QVMs, the fix must be engine-side.See #370 for full root cause analysis and test results.
Changes
code/qcommon/vm_local.hsyscallCountfield tovm_tstructcode/qcommon/vm.cVM_Call()code/server/sv_game.cSV_GameSystemCalls()Testing
Fixes #370