commit b1f4a09d6f79dc1af1b7247118472558c6186ca7
author Filip Perich <perich@google.com> Thu Sep 21 01:24:14 2023 +0000
committer Copybara-Service <copybara-worker@google.com> Wed Sep 20 18:35:32 2023 -0700
tree 389a215d7bb58a12ec2490939c2fd40e8fa0ab99
parent 544d19f0415840fd2f7426c21ac14f3cbc4d9f05

[zlib] Make internal window allocation consistent.

The default internal window memory allocation logic
creates a 32K + CHUNKCOPY_CHUNK_SIZE bytes large
buffer; however, the inflateCopy() function that is
supposed to copy a source stream to a destination
stream allocates just a 32K buffer, so a smaller
buffer. The rest of the optimized logic, however,
assumes that the window is 32K + CHUNKCOPY_CHUNK_SIZE
when calling inflate_fast_chunk_. That entry
assumption is actually specified in inffast_chunk.c
on lines 35:36.

Bug: b/292062232
Change-Id: I94686e745428162546f954b95fb424f315a71d76
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4876445
Reviewed-by: Adenilson Cavalcanti <cavalcantii@chromium.org>
Reviewed-by: Hans Wennborg <hans@chromium.org>
Commit-Queue: Filip Perich <perich@google.com>
Cr-Commit-Position: refs/heads/main@{#1199363}
NOKEYCHECK=True
GitOrigin-RevId: 8cd2a60036c5f0837e4d03848eb599393a33a132

contrib/optimizations/inflate.c

diff --git a/contrib/optimizations/inflate.c b/contrib/optimizations/inflate.c
index 6ed8716..2a8e0ef 100644
--- a/contrib/optimizations/inflate.c
+++ b/contrib/optimizations/inflate.c
@@ -1488,8 +1488,9 @@
     if (copy == Z_NULL) return Z_MEM_ERROR;
     window = Z_NULL;
     if (state->window != Z_NULL) {
-        window = (unsigned char FAR *)
-                 ZALLOC(source, 1U << state->wbits, sizeof(unsigned char));
+        window = (unsigned char FAR *)ZALLOC(
+            source, (1U << state->wbits) + CHUNKCOPY_CHUNK_SIZE,
+            sizeof(unsigned char));
         if (window == Z_NULL) {
             ZFREE(source, copy);
             return Z_MEM_ERROR;