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ppsspp: add ppsspp-0004 CWE-407 mutex waitingThreads dedup, extend unit test to 8/8 PASS

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ppsspp-0004: sceKernelLockMutex/CB and sceKernelLockLwMutex/CB (4 sites)
scan mutex->waitingThreads vector with std::find before push_back --
O(W) per lock attempt. Fix: parallel unordered_set for O(1) dedup.
Unit test extended to cover ppsspp-0004; all 8/8 PASS (ratios 5-27x).
This commit is contained in:
russell@unturf.com 2026-03-31 19:37:31 -04:00
parent 7fa196837a
commit 54827d6eb7
3 changed files with 79 additions and 0 deletions
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42
defects/ppsspp/test/PpssppKernelDedup.java
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@ -6,6 +6,7 @@ import java.util.*;
* ppsspp-0001: sceKernelThread waitingThreads vector dedup O(W^2)
* ppsspp-0002: sceKernelSemaphore waitingThreads vector dedup O(W^2)
* ppsspp-0003: IRJit byPage_ block removal O(P*B)
* ppsspp-0004: sceKernelMutex waitingThreads vector dedup O(W^2) -- 4 sites
*/
public class PpssppKernelDedup {
@ -169,6 +170,47 @@ public class PpssppKernelDedup {
if (ok) passed++; else failed++;
}
// --- Test 7: ppsspp-0004 correctness (mutex, 4 sites, same pattern) ---
// Models sceKernelLockMutex / sceKernelLockMutexCB /
// sceKernelLockLwMutex / sceKernelLockLwMutexCB tight-loop timeout.
{
int nThreads = 30;
int nRetries = 20; // each thread retries 20x under timeout
List<Integer> defect = new ArrayList<>();
List<Integer> fixed = new ArrayList<>();
Set<Integer> fixedSet = new HashSet<>();
for (int retry = 0; retry < nRetries; retry++) {
for (int tid = 0; tid < nThreads; tid++) {
addWaiter_defective(defect, tid);
addWaiter_fixed(fixed, fixedSet, tid);
}
}
boolean ok = defect.size() == nThreads && fixed.size() == nThreads;
System.out.println((ok ? "PASS" : "FAIL") + " ppsspp-0004 correctness: mutex waiter dedup (4 sites)");
if (ok) passed++; else failed++;
}
// --- Test 8: ppsspp-0004 performance (mutex contention scale) ---
{
int W = 3000;
List<Integer> defect = new ArrayList<>();
long t0 = System.nanoTime();
for (int tid = 0; tid < W; tid++) addWaiter_defective(defect, tid);
long defectNs = System.nanoTime() - t0;
List<Integer> fixed = new ArrayList<>();
Set<Integer> fixedSet = new HashSet<>();
t0 = System.nanoTime();
for (int tid = 0; tid < W; tid++) addWaiter_fixed(fixed, fixedSet, tid);
long fixedNs = System.nanoTime() - t0;
double ratio = (double) defectNs / Math.max(fixedNs, 1);
boolean ok = ratio > 5.0;
System.out.printf("%s ppsspp-0004 performance: W=%d defect=%.1fms fixed=%.1fms ratio=%.1fx%n",
ok ? "PASS" : "FAIL", W, defectNs / 1e6, fixedNs / 1e6, ratio);
if (ok) passed++; else failed++;
}
System.out.printf("%n%d/%d tests passed%n", passed, passed + failed);
if (failed > 0) System.exit(1);
}