zlib: reject windowBits=8 when mode=GZIP

It's also handled in C++ land now, per the previous commit, but intercepting it in JS land makes for prettier error messages. PR-URL: #33045 Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Gerhard Stöbich <[email protected]> Reviewed-By: David Carlier <[email protected]>
nodejs · May 11, 2020 · 736ca65 · 736ca65
1 parent ef25033
commit 736ca65
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Showing 4 changed files with 9 additions and 6 deletions.
diff --git a/lib/zlib.js b/lib/zlib.js
@@ -613,9 +613,11 @@ function Zlib(opts, mode) {
          mode === UNZIP)) {
       windowBits = 0;
     } else {
+      // `{ windowBits: 8 }` is valid for deflate but not gzip.
+      const min = Z_MIN_WINDOWBITS + (mode === GZIP ? 1 : 0);
       windowBits = checkRangesOrGetDefault(
         opts.windowBits, 'options.windowBits',
-        Z_MIN_WINDOWBITS, Z_MAX_WINDOWBITS, Z_DEFAULT_WINDOWBITS);
+        min, Z_MAX_WINDOWBITS, Z_DEFAULT_WINDOWBITS);
     }
 
     level = checkRangesOrGetDefault(

diff --git a/test/parallel/test-zlib-failed-init.js b/test/parallel/test-zlib-failed-init.js
@@ -21,7 +21,7 @@ assert.throws(
     code: 'ERR_OUT_OF_RANGE',
     name: 'RangeError',
     message: 'The value of "options.windowBits" is out of range. It must ' +
-             'be >= 8 and <= 15. Received 0'
+             'be >= 9 and <= 15. Received 0'
   }
 );
 

diff --git a/test/parallel/test-zlib-zero-windowBits.js b/test/parallel/test-zlib-zero-windowBits.js
@@ -28,6 +28,6 @@ const zlib = require('zlib');
     code: 'ERR_OUT_OF_RANGE',
     name: 'RangeError',
     message: 'The value of "options.windowBits" is out of range. ' +
-             'It must be >= 8 and <= 15. Received 0'
+             'It must be >= 9 and <= 15. Received 0'
   });
 }
diff --git a/test/parallel/test-zlib.js b/test/parallel/test-zlib.js
@@ -29,9 +29,10 @@ const fixtures = require('../common/fixtures');
 
 // Should not segfault.
 assert.throws(() => zlib.gzipSync(Buffer.alloc(0), { windowBits: 8 }), {
-  code: 'ERR_ZLIB_INITIALIZATION_FAILED',
-  name: 'Error',
-  message: 'Initialization failed',
+  code: 'ERR_OUT_OF_RANGE',
+  name: 'RangeError',
+  message: 'The value of "options.windowBits" is out of range. ' +
+           'It must be >= 9 and <= 15. Received 8',
 });
 
 let zlibPairs = [