From b78b277907898533bf221e1144612fce5615b9fb Mon Sep 17 00:00:00 2001
From: Raymond Hill <rhill@raymondhill.net>
Date: Sat, 4 Dec 2021 17:06:09 -0500
Subject: [PATCH] Add missing code to properly grow buffer

Related feedback:
- https://github.com/orgs/uBlockOrigin/teams/ublock-issues-volunteers/discussions/293

Related commit:
- https://github.com/gorhill/uBlock/commit/725e6931f58a81d36b18bb78663a8740c5e36231

Through all the changes, forgot to pay attention to scenarios
where the `filterData` needs to grow -- the buffer's defautl
size is set to accomodate default filter lists, and subscribing
to more lists would cause the static network filtering engine
to fail because the buffer was not resized when needed.
---
 src/js/static-net-filtering.js | 44 ++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/src/js/static-net-filtering.js b/src/js/static-net-filtering.js
index 612846f0d..bb556a2b4 100644
--- a/src/js/static-net-filtering.js
+++ b/src/js/static-net-filtering.js
@@ -361,22 +361,27 @@ const FILTER_DATA_PAGE_SIZE = 65536;
 
 let filterData = new Int32Array(FILTER_DATA_PAGE_SIZE * 5);
 let filterDataWritePtr = 2;
+function filterDataGrow(len) {
+    if ( len <= filterData.length ) { return; }
+    const newLen = (len + FILTER_DATA_PAGE_SIZE-1) & ~(FILTER_DATA_PAGE_SIZE-1);
+    const newBuf = new Int32Array(newLen);
+    newBuf.set(filterData);
+    filterData = newBuf;
+}
 function filterDataAlloc(...args) {
-    const idata = filterDataWritePtr;
     const len = args.length;
-    filterDataWritePtr += len;
-    if ( filterDataWritePtr > filterData.length ) {
-        const newLength = (filterDataWritePtr + FILTER_DATA_PAGE_SIZE-1) & ~(FILTER_DATA_PAGE_SIZE-1);
-        filterData = new Int32Array(newLength);
-    }
-    for ( let j = 0; j < len; j++ ) {
-        filterData[idata+j] = args[j];
+    const idata = filterDataAllocLen(len);
+    for ( let i = 0; i < len; i++ ) {
+        filterData[idata+i] = args[i];
     }
     return idata;
 }
 function filterDataAllocLen(len) {
     const idata = filterDataWritePtr;
     filterDataWritePtr += len;
+    if ( filterDataWritePtr > filterData.length ) {
+        filterDataGrow(filterDataWritePtr);
+    }
     return idata;
 }
 const filterSequenceAdd = (a, b) => {
@@ -395,10 +400,8 @@ function filterDataToSelfie() {
 function filterDataFromSelfie(selfie) {
     if ( typeof selfie !== 'string' || selfie === '' ) { return false; }
     const data = JSON.parse(selfie);
-    const newLen = (data.length + FILTER_DATA_PAGE_SIZE-1) & ~(FILTER_DATA_PAGE_SIZE-1);
-    if ( newLen > filterData.length ) {
-        filterData = new Int32Array(newLen);
-    }
+    if ( Array.isArray(data) === false ) { return false; }
+    filterDataGrow(data.length);
     filterDataWritePtr = data.length;
     filterData.set(data);
     return true;
@@ -446,6 +449,7 @@ function filterRefsToSelfie() {
 function filterRefsFromSelfie(selfie) {
     if ( typeof selfie !== 'string' || selfie === '' ) { return false; }
     const refs = JSON.parse(selfie);
+    if ( Array.isArray(refs) === false ) { return false; }
     for ( let i = 0; i < refs.length; i++ ) {
         const v = refs[i];
         switch ( v.t ) {
@@ -1836,10 +1840,10 @@ const FilterCollection = class {
         filterData[idata+1] = i;
     }
 
-    static create() {
+    static create(fid = -1) {
         return filterDataAlloc(
-            this.fid,   // fid
-            0           // i
+            fid !== -1 ? fid : FilterCollection.fid,
+            0
         );
     }
 
@@ -2279,10 +2283,10 @@ const FilterBucket = class extends FilterCollection {
 
     static create() {
         const idata = filterDataAllocLen(4);
-        filterData[idata+0] = FilterBucket.fid; // fid
-        filterData[idata+1] = super.create();   // icollection
-        filterData[idata+2] = 0;                // n
-        filterData[idata+3] = 0;                // $matchedUnit
+        filterData[idata+0] = FilterBucket.fid;             // fid
+        filterData[idata+1] = FilterCollection.create();    // icollection
+        filterData[idata+2] = 0;                            // n
+        filterData[idata+3] = 0;                            // $matchedUnit
         return idata;
     }
 
@@ -3681,7 +3685,7 @@ FilterContainer.prototype.freeze = function() {
     if ( this.optimized !== true && this.optimizeTaskId === undefined ) {
         this.optimizeTaskId = queueTask(( ) => {
             this.optimizeTaskId = undefined;
-            this.optimize(10);
+            this.optimize();
         }, 2000);
     }
 };