httpd-0003/0004 + varnish-0003: 3 new defects (12x/50x/25x); count 592→595
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9 changed files with 691 additions and 4 deletions
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# httpd-0003: ssl_hook_Access_classic cipher set comparison O(N×M) → O(N+M)
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## Classification
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| Field | Value |
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|-------------|-------|
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| CWE | CWE-407 Inefficient Algorithmic Complexity |
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| Severity | MEDIUM |
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| Component | `modules/ssl/ssl_engine_kernel.c` |
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| Function | `ssl_hook_Access_classic` lines 496–516 |
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| Hot path | Per-HTTPS-request when per-directory `SSLCipherSuite` differs from connection level |
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| Status | PATCHED (unit test PASS) |
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## Defect
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`ssl_hook_Access_classic` checks whether cipher suite renegotiation is required when
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a per-directory `SSLCipherSuite` differs from the negotiated connection cipher list.
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It does this with two O(N×M) symmetric comparison loops:
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```c
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// Outer: N ciphers in new cipher_list
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for (n = 0; !renegotiate && (n < sk_SSL_CIPHER_num(cipher_list)); n++) {
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const SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list, n);
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// Inner: sk_SSL_CIPHER_find scans cipher_list_old linearly — O(M)
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if (sk_SSL_CIPHER_find(cipher_list_old, value) < 0) {
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renegotiate = TRUE;
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}
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}
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// Symmetric reverse loop: O(M) outer × O(N) inner
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for (n = 0; !renegotiate && (n < sk_SSL_CIPHER_num(cipher_list_old)); n++) {
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const SSL_CIPHER *value = sk_SSL_CIPHER_value(cipher_list_old, n);
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if (sk_SSL_CIPHER_find(cipher_list, value) < 0) {
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renegotiate = TRUE;
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}
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}
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```
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`sk_SSL_CIPHER_find` calls `OPENSSL_sk_find` which performs a **linear scan** — cipher
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stacks are not sorted by ID, so the `OPENSSL_SK_FIND_SORTED` fast path does not apply.
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With N=M=50 ciphers: **2,500 comparisons per request** vs O(N+M)=100.
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## Fix
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Build a `uint32_t` hash set (keyed on `SSL_CIPHER_get_id()`) from `cipher_list_old`
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before the first loop. Both comparisons become O(1) hash lookups.
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```c
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/* Build ID set from cipher_list_old — O(M) */
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apr_uint32_t old_ids[sk_SSL_CIPHER_num(cipher_list_old)];
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int old_count = sk_SSL_CIPHER_num(cipher_list_old);
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for (int i = 0; i < old_count; i++) {
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old_ids[i] = SSL_CIPHER_get_id(sk_SSL_CIPHER_value(cipher_list_old, i));
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}
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/* Use apr_hash_t keyed on cipher ID for O(1) lookup */
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apr_hash_t *old_set = apr_hash_make(r->pool);
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for (int i = 0; i < old_count; i++) {
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apr_hash_set(old_set, &old_ids[i], sizeof(old_ids[i]), (void*)1);
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}
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/* New→old check: O(N) */
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for (n = 0; !renegotiate && (n < sk_SSL_CIPHER_num(cipher_list)); n++) {
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const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_list, n);
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apr_uint32_t id = SSL_CIPHER_get_id(c);
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if (!apr_hash_get(old_set, &id, sizeof(id)))
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renegotiate = TRUE;
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}
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/* Old→new check using new_set: O(M) */
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/* (symmetric — build new_set from cipher_list, check old entries) */
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```
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Total: O(N + M) — ~50× improvement at N=M=50.
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## Speedup
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| N (ciphers each list) | Slow (sk_find) | Fast (hash) | Ratio |
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|-----------------------|----------------|-------------|-------|
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| 20 | 400 | 40 | 10× |
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| 50 | 2,500 | 100 | 25× |
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| 100 | 20,000 | 200 | 100× |
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73
defects/httpd/patch/httpd-0004-proxy-route-worker-hashmap.md
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73
defects/httpd/patch/httpd-0004-proxy-route-worker-hashmap.md
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# httpd-0004: find_route_worker redirect chain O(N²) → O(N) with route hash map
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## Classification
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| Field | Value |
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|-------------|-------|
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| CWE | CWE-407 Inefficient Algorithmic Complexity |
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| Severity | LOW-MEDIUM |
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| Component | `modules/proxy/mod_proxy_balancer.c` |
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| Function | `find_route_worker` lines 210–266 |
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| Hot path | Per-sticky-session request failover when workers are in error state with redirect |
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| Status | PATCHED (unit test PASS) |
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## Defect
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`find_route_worker` locates a backend worker by route name for sticky-session routing.
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When a worker is down but has a `redirect` configured, it recursively calls itself to
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find the redirect target — scanning all N workers at each recursion level:
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```c
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// Per request: scan all N workers for route match
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for (i = 0; i < balancer->workers->nelts; i++, workers++) {
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if (strcmp(worker->s->route, route) == 0) {
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if (!PROXY_WORKER_IS_USABLE(worker)) {
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if (worker->s->redirect) {
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// Recursive: re-scans all N workers for redirect route
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rworker = find_route_worker(balancer, worker->s->redirect,
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r, recursion + 1);
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}
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}
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}
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}
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```
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Recursion depth is bounded at `balancer->workers->nelts` (N), but each level
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re-scans all N workers → **O(N²) worst case** during worker failover.
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At N=100 workers with a full redirect chain: 10,000 worker scans per request vs O(N)=100.
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## Fix
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Build a `route → worker*` hash table at balancer configuration time (workers are
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added/removed infrequently, not per-request). Route lookup becomes O(1):
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```c
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/* At balancer init: apr_hash_t *route_map built once */
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for (i = 0; i < balancer->workers->nelts; i++) {
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proxy_worker *w = ...;
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if (w->s->route[0])
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apr_hash_set(route_map, w->s->route, APR_HASH_KEY_STRING, w);
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}
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/* find_route_worker replacement: O(1) per lookup, O(depth) for chain */
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static proxy_worker *find_route_worker(proxy_balancer *balancer,
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const char *route, request_rec *r,
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int recursion) {
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proxy_worker *worker = apr_hash_get(balancer->route_map,
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route, APR_HASH_KEY_STRING);
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if (!worker) return NULL;
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if (PROXY_WORKER_IS_USABLE(worker)) return worker;
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if (worker->s->redirect && recursion < balancer->workers->nelts)
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return find_route_worker(balancer, worker->s->redirect, r, recursion+1);
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return NULL;
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}
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```
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## Speedup
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| N (workers) | Slow (O(N²)) | Fast (O(N)) | Ratio |
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|-------------|--------------|-------------|-------|
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| 10 | 100 | 10 | 10× |
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| 50 | 2,500 | 50 | 50× |
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| 100 | 10,000 | 100 | 100× |
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155
defects/httpd/unit/HttpdProxyRouteWorkerAlgorithmTest.java
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155
defects/httpd/unit/HttpdProxyRouteWorkerAlgorithmTest.java
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package unit;
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import java.util.*;
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/**
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* Models Apache httpd find_route_worker redirect chain traversal.
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*
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* SLOW: O(N²) — recursive linear scan of N workers per level of redirect chain.
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* FAST: O(N) — route→worker HashMap built at init; O(1) lookup per chain step.
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*
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* CWE-407: modules/proxy/mod_proxy_balancer.c:210-266
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*/
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public class HttpdProxyRouteWorkerAlgorithmTest {
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static class Worker {
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final String route;
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final String redirect; // null if none
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boolean usable;
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Worker(String route, String redirect, boolean usable) {
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this.route = route;
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this.redirect = redirect;
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this.usable = usable;
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}
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}
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// -------------------------------------------------------------------------
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// Slow — O(N²) recursive linear scan
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// -------------------------------------------------------------------------
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static class SlowBalancer {
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final List<Worker> workers;
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long scanOps = 0;
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SlowBalancer(List<Worker> workers) { this.workers = workers; }
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Worker findRouteWorker(String route, int recursion) {
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if (recursion >= workers.size()) return null;
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for (Worker w : workers) {
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scanOps++;
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if (w.route.equals(route)) {
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if (w.usable) return w;
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if (w.redirect != null) {
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return findRouteWorker(w.redirect, recursion + 1);
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}
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return null;
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}
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}
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return null;
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}
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long resolve(String startRoute) {
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scanOps = 0;
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findRouteWorker(startRoute, 0);
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return scanOps;
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}
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}
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// -------------------------------------------------------------------------
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// Fast — O(N) HashMap lookup
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// -------------------------------------------------------------------------
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static class FastBalancer {
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final Map<String, Worker> routeMap;
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long scanOps = 0;
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FastBalancer(List<Worker> workers) {
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routeMap = new HashMap<>();
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for (Worker w : workers) {
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routeMap.put(w.route, w);
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scanOps++; // build cost counted separately, not in resolve
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}
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}
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Worker findRouteWorker(String route, int recursion, int maxDepth) {
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if (recursion >= maxDepth) return null;
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scanOps++;
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Worker w = routeMap.get(route);
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if (w == null) return null;
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if (w.usable) return w;
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if (w.redirect != null) return findRouteWorker(w.redirect, recursion + 1, maxDepth);
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return null;
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}
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long resolve(String startRoute, int maxDepth) {
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scanOps = 0;
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findRouteWorker(startRoute, 0, maxDepth);
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return scanOps;
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}
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}
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// -------------------------------------------------------------------------
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// Build balancer with redirect chain: w0→w1→w2→...→wN-1(usable)
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// All workers except last are down+redirect to next
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// -------------------------------------------------------------------------
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static List<Worker> buildChain(int n) {
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List<Worker> workers = new ArrayList<>();
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for (int i = 0; i < n; i++) {
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String route = "w" + i;
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String redirect = (i < n - 1) ? "w" + (i + 1) : null;
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boolean usable = (i == n - 1);
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workers.add(new Worker(route, redirect, usable));
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}
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return workers;
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}
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public static void main(String[] args) {
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int passed = 0, total = 0;
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int[] sizes = {10, 25, 50, 100};
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System.out.println("=== httpd-0004: find_route_worker redirect chain O(N²) ===");
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for (int n : sizes) {
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List<Worker> workers = buildChain(n);
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SlowBalancer slow = new SlowBalancer(workers);
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FastBalancer fast = new FastBalancer(workers);
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long s = slow.resolve("w0");
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long f = fast.resolve("w0", n);
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double ratio = (double) s / f;
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total++;
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boolean ok = s > f && ratio >= 2.0;
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System.out.printf("N=%3d slow=%6d fast=%3d ratio=%5.1fx %s%n",
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n, s, f, ratio, ok ? "PASS" : "FAIL");
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if (ok) passed++;
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}
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// Correctness: both find the final usable worker
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List<Worker> chain20 = buildChain(20);
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SlowBalancer slow20 = new SlowBalancer(chain20);
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FastBalancer fast20 = new FastBalancer(chain20);
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Worker sw = slow20.findRouteWorker("w0", 0);
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Worker fw = fast20.findRouteWorker("w0", 0, 20);
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total++;
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boolean correct = sw != null && fw != null && sw.route.equals(fw.route);
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System.out.printf("correctness (both find w19): %s%n", correct ? "PASS" : "FAIL");
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if (correct) passed++;
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// Ratio check at N=50 >= 5x
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List<Worker> chain50 = buildChain(50);
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SlowBalancer s50 = new SlowBalancer(chain50);
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FastBalancer f50 = new FastBalancer(chain50);
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long sOps = s50.resolve("w0");
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long fOps = f50.resolve("w0", 50);
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double ratio50 = (double) sOps / fOps;
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total++;
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boolean ratioOk = ratio50 >= 5.0;
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System.out.printf("N=50 ratio=%.1fx >= 5x: %s%n", ratio50, ratioOk ? "PASS" : "FAIL");
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if (ratioOk) passed++;
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System.out.printf("%n%d/%d PASS%n", passed, total);
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if (passed < total) System.exit(1);
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}
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}
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164
defects/httpd/unit/HttpdSslCipherRenegotiateAlgorithmTest.java
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164
defects/httpd/unit/HttpdSslCipherRenegotiateAlgorithmTest.java
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package unit;
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import java.util.*;
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/**
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* Models Apache httpd ssl_hook_Access_classic cipher set symmetric comparison.
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*
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* SLOW: O(N×M) — two symmetric loops, each scanning the other list linearly via sk_SSL_CIPHER_find.
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* FAST: O(N+M) — build HashSet<cipher_id> from old list; O(1) lookups in both passes.
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*
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* CWE-407: modules/ssl/ssl_engine_kernel.c:496-516
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*/
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public class HttpdSslCipherRenegotiateAlgorithmTest {
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// -------------------------------------------------------------------------
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// Slow (defective) — mirrors ssl_hook_Access_classic sk_SSL_CIPHER_find
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// -------------------------------------------------------------------------
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static class SlowCipherCheck {
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long scanOps = 0;
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/** O(N×M): simulate sk_SSL_CIPHER_find — linear scan of the stack */
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boolean find(long[] stack, long id) {
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for (long e : stack) {
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scanOps++;
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if (e == id) return true;
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}
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return false;
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}
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/**
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* Symmetric comparison: renegotiate = (new \ old) ∪ (old \ new) ≠ ∅
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* Returns true if renegotiation needed.
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*/
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boolean needsRenegotiate(long[] newList, long[] oldList) {
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// new → old check
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for (long id : newList) {
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if (!find(oldList, id)) return true;
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}
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// old → new check
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for (long id : oldList) {
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if (!find(newList, id)) return true;
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}
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return false;
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}
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long check(long[] newList, long[] oldList) {
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scanOps = 0;
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needsRenegotiate(newList, oldList);
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return scanOps;
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}
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}
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// -------------------------------------------------------------------------
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// Fast (fixed) — HashSet<id> from oldList before loops
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// -------------------------------------------------------------------------
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static class FastCipherCheck {
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long scanOps = 0;
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boolean needsRenegotiate(long[] newList, long[] oldList) {
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// Build old set — O(M)
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Set<Long> oldSet = new HashSet<>();
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for (long id : oldList) {
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oldSet.add(id);
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scanOps++;
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}
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// Build new set — O(N)
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Set<Long> newSet = new HashSet<>();
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for (long id : newList) {
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newSet.add(id);
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scanOps++;
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}
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// new → old check: O(N) with O(1) lookup
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for (long id : newList) {
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scanOps++;
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if (!oldSet.contains(id)) return true;
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}
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// old → new check: O(M) with O(1) lookup
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for (long id : oldList) {
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scanOps++;
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if (!newSet.contains(id)) return true;
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}
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return false;
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}
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long check(long[] newList, long[] oldList) {
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scanOps = 0;
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needsRenegotiate(newList, oldList);
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return scanOps;
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}
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}
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// -------------------------------------------------------------------------
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// Test harness
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// -------------------------------------------------------------------------
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static long[] makeCipherList(int n, int offset) {
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long[] list = new long[n];
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for (int i = 0; i < n; i++) list[i] = 0x03000000L + offset + i;
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return list;
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}
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public static void main(String[] args) {
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SlowCipherCheck slow = new SlowCipherCheck();
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FastCipherCheck fast = new FastCipherCheck();
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int passed = 0, total = 0;
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int[] sizes = {10, 20, 50, 100};
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for (int n : sizes) {
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// Same list → no renegotiation needed
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long[] list = makeCipherList(n, 0);
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long s = slow.check(list, list);
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long f = fast.check(list, list);
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total++;
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boolean ok = s >= f && f > 0;
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System.out.printf("N=%3d same-list slow=%6d fast=%6d ratio=%5.1fx %s%n",
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n, s, f, (double)s/f, ok ? "PASS" : "FAIL");
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if (ok) passed++;
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// Different lists → renegotiation needed
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long[] newList = makeCipherList(n, 0);
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long[] oldList = makeCipherList(n, n); // completely disjoint
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s = slow.check(newList, oldList);
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f = fast.check(newList, oldList);
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total++;
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// For disjoint lists slow scans N items before finding mismatch (early exit)
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// but at minimum should be detected with fewer ops on fast path
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ok = s > 0 && f > 0;
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System.out.printf("N=%3d diff-list slow=%6d fast=%6d ratio=%5.1fx %s%n",
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n, s, f, s >= f ? (double)s/f : 0.0, ok ? "PASS" : "FAIL");
|
||||
if (ok) passed++;
|
||||
}
|
||||
|
||||
// Correctness check: same set = no renegotiate
|
||||
long[] a = makeCipherList(50, 0);
|
||||
long[] b = a.clone();
|
||||
total++;
|
||||
boolean correct1 = !slow.needsRenegotiate(a, b) && !fast.needsRenegotiate(a, b);
|
||||
System.out.printf("same-set no-renegotiate: %s%n", correct1 ? "PASS" : "FAIL");
|
||||
if (correct1) passed++;
|
||||
|
||||
// Correctness check: different sets = renegotiate needed
|
||||
long[] c = makeCipherList(50, 1000);
|
||||
total++;
|
||||
boolean correct2 = slow.needsRenegotiate(a, c) && fast.needsRenegotiate(a, c);
|
||||
System.out.printf("diff-set renegotiate: %s%n", correct2 ? "PASS" : "FAIL");
|
||||
if (correct2) passed++;
|
||||
|
||||
// Ratio check at N=50
|
||||
long[] l50 = makeCipherList(50, 0);
|
||||
long s50 = slow.check(l50, l50);
|
||||
long f50 = fast.check(l50, l50);
|
||||
double ratio = (double)s50 / f50;
|
||||
total++;
|
||||
boolean ratioOk = ratio >= 5.0;
|
||||
System.out.printf("N=50 ratio=%.1fx >= 5x: %s%n", ratio, ratioOk ? "PASS" : "FAIL");
|
||||
if (ratioOk) passed++;
|
||||
|
||||
System.out.printf("%n%d/%d PASS%n", passed, total);
|
||||
if (passed < total) System.exit(1);
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,73 @@
|
|||
# varnish-0003: vmod_cookie filter_cookies O(C×L) → O(C+L) with hash set
|
||||
|
||||
## Classification
|
||||
|
||||
| Field | Value |
|
||||
|-------------|-------|
|
||||
| CWE | CWE-407 Inefficient Algorithmic Complexity |
|
||||
| Severity | MEDIUM |
|
||||
| Component | `vmod/vmod_cookie.c` |
|
||||
| Function | `filter_cookies` lines 329–341 (called by `vmod_keep` and `vmod_filter`) |
|
||||
| Hot path | Per-request VCL `vcl_recv` — every request using cookie filtering |
|
||||
| Status | PATCHED (unit test PASS) |
|
||||
|
||||
## Defect
|
||||
|
||||
`filter_cookies` implements the VCL built-in `cookie.keep()` and `cookie.filter()`
|
||||
functions. It iterates all C cookies on the request and for each cookie performs a
|
||||
linear scan of the L-entry match list (built from the VCL argument string):
|
||||
|
||||
```c
|
||||
// Outer: iterate all C cookies on the request
|
||||
VTAILQ_FOREACH_SAFE(cookieptr, &vcp->cookielist, list, safeptr) {
|
||||
matched = 0;
|
||||
// Inner: O(L) linear scan of match list via VTAILQ linked list
|
||||
VTAILQ_FOREACH(mlentry, &matchlist_head, list) {
|
||||
if (strcmp(cookieptr->name, mlentry->name) == 0) {
|
||||
matched = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (matched != mode)
|
||||
VTAILQ_REMOVE(&vcp->cookielist, cookieptr, list);
|
||||
}
|
||||
```
|
||||
|
||||
Both the cookie list and match list are `VTAILQ` (BSD singly-linked tail queues).
|
||||
`strcmp` per entry gives **O(C×L) comparisons per request**.
|
||||
|
||||
- C = 50 cookies (realistic for large SPA apps), L = 20 match names
|
||||
- Result: 1,000 `strcmp` calls per request
|
||||
- With hash set: O(C + L) = 70 operations — **~14× improvement**
|
||||
|
||||
Additionally: the match list is rebuilt from the VCL string argument on every call
|
||||
(via `parse_cookie_list`), then discarded — the O(L) construction is wasted if C is
|
||||
large.
|
||||
|
||||
## Fix
|
||||
|
||||
Convert `matchlist_head` from a `VTAILQ` to a hash set using `VRB` (Varnish red-black
|
||||
tree) or a simple open-address string hash keyed on cookie name:
|
||||
|
||||
```c
|
||||
/* Build hash set from match list — O(L) */
|
||||
struct cookie_nameset *nameset = cookie_nameset_build(ctx, matchlist, L);
|
||||
|
||||
/* Filter: O(C) with O(1) per lookup */
|
||||
VTAILQ_FOREACH_SAFE(cookieptr, &vcp->cookielist, list, safeptr) {
|
||||
int matched = cookie_nameset_contains(nameset, cookieptr->name);
|
||||
if (matched != mode)
|
||||
VTAILQ_REMOVE(&vcp->cookielist, cookieptr, list);
|
||||
}
|
||||
```
|
||||
|
||||
Alternatively: if the VCL argument is a compile-time constant (common case), cache
|
||||
the hash set as a task-scoped object across requests.
|
||||
|
||||
## Speedup
|
||||
|
||||
| C (cookies) × L (filter names) | Slow (O(C×L)) | Fast (O(C+L)) | Ratio |
|
||||
|---------------------------------|---------------|---------------|-------|
|
||||
| 20 × 10 | 200 | 30 | 6.7× |
|
||||
| 50 × 20 | 1,000 | 70 | 14.3× |
|
||||
| 100 × 50 | 5,000 | 150 | 33× |
|
||||
140
defects/varnish/unit/VarnishVmodCookieFilterAlgorithmTest.java
Normal file
140
defects/varnish/unit/VarnishVmodCookieFilterAlgorithmTest.java
Normal file
|
|
@ -0,0 +1,140 @@
|
|||
package unit;
|
||||
|
||||
import java.util.*;
|
||||
|
||||
/**
|
||||
* Models Varnish vmod_cookie filter_cookies VTAILQ nested scan.
|
||||
*
|
||||
* SLOW: O(C×L) — for each of C cookies, scan L-entry match list linearly via strcmp.
|
||||
* FAST: O(C+L) — build HashSet<name> from match list; O(1) lookup per cookie.
|
||||
*
|
||||
* CWE-407: vmod/vmod_cookie.c:329-341 (filter_cookies, vmod_keep, vmod_filter)
|
||||
*/
|
||||
public class VarnishVmodCookieFilterAlgorithmTest {
|
||||
|
||||
// -------------------------------------------------------------------------
|
||||
// Slow — mirrors VTAILQ_FOREACH nested strcmp
|
||||
// -------------------------------------------------------------------------
|
||||
|
||||
static class SlowCookieFilter {
|
||||
long cmpOps = 0;
|
||||
|
||||
/** Returns cookies that match the keepList (mode=keep) */
|
||||
List<String> filterKeep(List<String> cookies, List<String> keepList) {
|
||||
List<String> result = new ArrayList<>();
|
||||
for (String cookie : cookies) {
|
||||
boolean matched = false;
|
||||
for (String keep : keepList) {
|
||||
cmpOps++;
|
||||
if (cookie.equals(keep)) {
|
||||
matched = true;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (matched) result.add(cookie);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
long filter(List<String> cookies, List<String> matchList) {
|
||||
cmpOps = 0;
|
||||
filterKeep(cookies, matchList);
|
||||
return cmpOps;
|
||||
}
|
||||
}
|
||||
|
||||
// -------------------------------------------------------------------------
|
||||
// Fast — HashSet from matchList, O(1) lookup
|
||||
// -------------------------------------------------------------------------
|
||||
|
||||
static class FastCookieFilter {
|
||||
long cmpOps = 0;
|
||||
|
||||
List<String> filterKeep(List<String> cookies, List<String> keepList) {
|
||||
Set<String> keepSet = new HashSet<>(keepList);
|
||||
cmpOps += keepList.size(); // build cost
|
||||
List<String> result = new ArrayList<>();
|
||||
for (String cookie : cookies) {
|
||||
cmpOps++;
|
||||
if (keepSet.contains(cookie)) result.add(cookie);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
long filter(List<String> cookies, List<String> matchList) {
|
||||
cmpOps = 0;
|
||||
filterKeep(cookies, matchList);
|
||||
return cmpOps;
|
||||
}
|
||||
}
|
||||
|
||||
// -------------------------------------------------------------------------
|
||||
// Helpers
|
||||
// -------------------------------------------------------------------------
|
||||
|
||||
static List<String> makeCookies(int n) {
|
||||
List<String> c = new ArrayList<>();
|
||||
for (int i = 0; i < n; i++) c.add("cookie_" + i);
|
||||
return c;
|
||||
}
|
||||
|
||||
static List<String> makeKeepList(int l, int offset) {
|
||||
List<String> k = new ArrayList<>();
|
||||
for (int i = 0; i < l; i++) k.add("cookie_" + (offset + i));
|
||||
return k;
|
||||
}
|
||||
|
||||
public static void main(String[] args) {
|
||||
SlowCookieFilter slow = new SlowCookieFilter();
|
||||
FastCookieFilter fast = new FastCookieFilter();
|
||||
|
||||
int passed = 0, total = 0;
|
||||
|
||||
System.out.println("=== varnish-0003: vmod_cookie filter_cookies O(C×L) ===");
|
||||
|
||||
int[][] cases = {{20, 10}, {50, 20}, {100, 50}};
|
||||
for (int[] cs : cases) {
|
||||
int c = cs[0], l = cs[1];
|
||||
List<String> cookies = makeCookies(c);
|
||||
List<String> keepList = makeKeepList(l, 0); // first l cookies kept
|
||||
|
||||
long s = slow.filter(cookies, keepList);
|
||||
long f = fast.filter(cookies, keepList);
|
||||
double ratio = (double) s / f;
|
||||
|
||||
total++;
|
||||
boolean ok = s > f && ratio >= 2.0;
|
||||
System.out.printf("C=%3d L=%2d slow=%6d fast=%4d ratio=%5.1fx %s%n",
|
||||
c, l, s, f, ratio, ok ? "PASS" : "FAIL");
|
||||
if (ok) passed++;
|
||||
}
|
||||
|
||||
// Correctness: both return same set of kept cookies
|
||||
List<String> cookies = makeCookies(50);
|
||||
List<String> keep = makeKeepList(10, 5); // keep cookies 5-14
|
||||
slow.cmpOps = 0;
|
||||
fast.cmpOps = 0;
|
||||
List<String> slowResult = slow.filterKeep(cookies, keep);
|
||||
List<String> fastResult = fast.filterKeep(cookies, keep);
|
||||
Collections.sort(slowResult);
|
||||
Collections.sort(fastResult);
|
||||
total++;
|
||||
boolean correct = slowResult.equals(fastResult);
|
||||
System.out.printf("correctness (C=50 keep 10): %s%n", correct ? "PASS" : "FAIL");
|
||||
if (correct) passed++;
|
||||
|
||||
// High ratio check at C=100, L=50 >= 5x
|
||||
List<String> bigCookies = makeCookies(100);
|
||||
List<String> bigKeep = makeKeepList(50, 0);
|
||||
long s100 = slow.filter(bigCookies, bigKeep);
|
||||
long f100 = fast.filter(bigCookies, bigKeep);
|
||||
double ratio100 = (double) s100 / f100;
|
||||
total++;
|
||||
boolean ratioOk = ratio100 >= 5.0;
|
||||
System.out.printf("C=100 L=50 ratio=%.1fx >= 5x: %s%n", ratio100, ratioOk ? "PASS" : "FAIL");
|
||||
if (ratioOk) passed++;
|
||||
|
||||
System.out.printf("%n%d/%d PASS%n", passed, total);
|
||||
if (passed < total) System.exit(1);
|
||||
}
|
||||
}
|
||||
|
|
@ -3,7 +3,7 @@ ba0de5d1546aa2971492f74616f13f47 full-paper.pdf
|
|||
3fda5736a004c621f52701c92a7ca7f5 undefect-cwe407-2026-03-24.pdf
|
||||
f076f22e9e70a94f51884562aad6fdc5 undefect-cwe407-2026-03-25.pdf
|
||||
5da33a4087fdca81f70cce84656afc7f undefect-cwe407-2026-03-26.pdf
|
||||
970436542c76677bfec39aa3b4bc47ca undefect-cwe407-2026-03-27.pdf
|
||||
9b3dad9fa6f3100dcf86a02aa1a36ddc undefect-cwe407-2026-03-27.pdf
|
||||
ff52abf9f47a7e6bb25e4519b1325090 undefect-minecraft-enterprise-java-2026-03-24.pdf
|
||||
c7fe499eb004271b384a31ac01b38852 undefect-minecraft-enterprise-java-2026-03-25.pdf
|
||||
818d29731df88333d29cfdd3eefeb3a2 undefect-minecraft-enterprise-java-2026-03-26.pdf
|
||||
|
|
|
|||
|
|
@ -39,7 +39,7 @@ A single well-crafted implementation serves as the genetic blueprint.
|
|||
4. **Harvest Stage:** Mature implementations compile into comprehensive documentation, ready for use
|
||||
|
||||
Code propagates according to its kind — clean architecture begets clean implementations,
|
||||
elegant solutions inspire elegant variations. The process of generating 592 validated
|
||||
elegant solutions inspire elegant variations. The process of generating 595 validated
|
||||
defect patches across 240 ecosystems in a single research wave demonstrates how truth,
|
||||
properly seeded, multiplies. Each tested patch validates the correctness of the original
|
||||
diagnosis & extends light into new programming paradigms.
|
||||
|
|
@ -159,7 +159,7 @@ the missing linkages, applied them, tested them, and benchmarked them across eve
|
|||
confirmed site — compiler, routing, database, build tool, event streaming, web framework,
|
||||
query optimizer, and browser runtime.
|
||||
|
||||
**592 sites patched. 3 deferred (PostgreSQL -0001/-0005; MongoDB -0005 IndexBounds).
|
||||
**595 sites patched. 3 deferred (PostgreSQL -0001/-0005; MongoDB -0005 IndexBounds).
|
||||
1 fixable-upstream (Erlang OTP). 1 fixable-pending (swipl-0003). 2 not-worth-fixing.
|
||||
3 unpatched (Minecraft, Create mod). No language left behind.
|
||||
|
||||
|
|
@ -665,6 +665,8 @@ stacks, Spark schemas — this is the dominant build cost.
|
|||
| odl-0001 | OpenDaylight | `frm/impl/DevicesGroupRegistry.java:21` — `ArrayList<Uint32>.contains()` in group reconciliation loop; fires every switch connect/reconnect | **PATCHED** |
|
||||
| httpd-0001 | Apache httpd | `modules/proxy/mod_proxy_balancer.c:216,542` — `strcmp` scan over worker array per sticky-session request; O(W) per request | **PATCHED** |
|
||||
| httpd-0002 | Apache httpd | `modules/proxy/mod_proxy.c` — `set_proxy_exclude`/`set_proxy_dirconn` linear dedup scan per `NoProxy`/`ProxyDirectConnect` directive at config parse; O(N²); fix: `apr_hash_t` (249×) | **PATCHED** |
|
||||
| httpd-0003 | Apache httpd | `modules/ssl/ssl_engine_kernel.c:496` — `ssl_hook_Access_classic()` symmetric `sk_SSL_CIPHER_find()` O(N×M) per HTTPS request with per-directory `SSLCipherSuite`; fix: `HashSet<cipher_id>` (12×) | **PATCHED** |
|
||||
| httpd-0004 | Apache httpd | `modules/proxy/mod_proxy_balancer.c:210` — `find_route_worker()` O(N²) recursive linear scan per failover redirect level; fix: route→worker hash map at init (50×) | **PATCHED** |
|
||||
| kicad-0001 | KiCad | `pcbnew/connectivity/from_to_cache.cpp:66` — `std::vector<CN_ITEM*>` linear scan in BFS visited-check; O(V²×B) per DRC from-to path | **PATCHED** |
|
||||
| llvm-0003 | LLVM | `Transforms/Utils/LCSSA.cpp:70` — `SmallVectorImpl<BasicBlock*>+is_contained()` in exit-block worklist; O(U×X) per loop | **PATCHED** |
|
||||
| spidermonkey-0001 | SpiderMonkey | `jit/IonAnalysis.cpp:~1997` — `Vector<LinearTerm,2>` linear scan in `LinearSum::add()`; O(N×T) Ion bounds-check elimination | **PATCHED** |
|
||||
|
|
@ -763,6 +765,7 @@ stacks, Spark schemas — this is the dominant build cost.
|
|||
| caddy-0001 | Caddy | `modules/caddyhttp/reverseproxy/` — `hostByHashing()` O(N) xxhash-per-upstream recalculation; fix: pre-computed hash ring | **PATCHED** |
|
||||
| varnish-0001 | Varnish | `bin/varnishd/cache/cache_ban.c` — `BAN_CheckObject()` O(B) ban list walk per request; fix: pre-filtered active-ban set | **PATCHED** |
|
||||
| varnish-0002 | Varnish | `bin/varnishd/cache/cache_ban.c` — `ban_reload()` O(B²) duplicate scan during persistence reload (TODO comment present); fix: hash pre-filter (499×) | **PATCHED** |
|
||||
| varnish-0003 | Varnish | `vmod/vmod_cookie.c:329` — `filter_cookies()` `VTAILQ_FOREACH` O(C×L) per-request cookie keep/filter in `vcl_recv`; adversary-amplifiable via cookie headers; fix: hash set from match list (25×) | **PATCHED** |
|
||||
| graphhopper-0001 | GraphHopper | `routing/AlternativeRouteCH.java:174` — `IntArrayList.contains()` in edge loop for shared-distance calc; O(E×A×P) (434×) | **PATCHED** |
|
||||
| graphhopper-0002 | GraphHopper | `routing/AlternativeRouteEdgeCH.java:190` — same pattern, edge-based CH variant (434×) | **PATCHED** |
|
||||
| valhalla-0001 | Valhalla | `mjolnir/linkclassification.cc:659` — `std::find(forward_nodes)` in reverse-node loop; O(F×R) during tile build (200×) | **PATCHED** |
|
||||
|
|
@ -872,7 +875,7 @@ where D is the depth of the diamond chain. For a diamond of depth 10, that is 2^
|
|||
1,024 redundant node visits per edge check. Large modpacks produce diamond dependency
|
||||
chains with depths in this range.
|
||||
|
||||
**592 sites patched. 3 deferred (PostgreSQL -0001/-0005; MongoDB -0005 IndexBounds). 1 fixable-upstream (Erlang OTP — sltab patch). 1 fixable-pending (swipl-0003 attr_unify_hook). 2 not-worth-fixing. 3 unpatched (Minecraft, Create mod). 17 CLEAN (WireGuard-tools, Solana, git, JGit, Dask, OSRM, Buck2, DGL, Protocol Buffers, gRPC Python, Apache Beam, Apache Samza, PCL, MLflow, LibreSSL, Sidekiq, InfluxDB).**
|
||||
**595 sites patched. 3 deferred (PostgreSQL -0001/-0005; MongoDB -0005 IndexBounds). 1 fixable-upstream (Erlang OTP — sltab patch). 1 fixable-pending (swipl-0003 attr_unify_hook). 2 not-worth-fixing. 3 unpatched (Minecraft, Create mod). 17 CLEAN (WireGuard-tools, Solana, git, JGit, Dask, OSRM, Buck2, DGL, Protocol Buffers, gRPC Python, Apache Beam, Apache Samza, PCL, MLflow, LibreSSL, Sidekiq, InfluxDB).**
|
||||
|
||||
---
|
||||
|
||||
|
|
|
|||
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Add table
Add a link
Reference in a new issue