Fix out-of-bounds in infcover tests.

Upstream zlib pull request: https://github.com/madler/zlib/pull/602

Bug: 225069280
Change-Id: I548a836096323053af225083916893b851532980
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3546708


Reviewed-by: Noel Gordon <noel@chromium.org>
Commit-Queue: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/main@{#984579}
NOKEYCHECK=True
GitOrigin-RevId: afa134512eec0ab985c64bc39e39b0bb5212f8f6

contrib/tests/infcover.cc

@@ -395,7 +395,9 @@ void cover_support(void)
     mem_setup(&strm);
     strm.avail_in = 0;
     strm.next_in = Z_NULL;
-    ret = inflateInit_(&strm, ZLIB_VERSION - 1, (int)sizeof(z_stream));
+    char versioncpy[] = ZLIB_VERSION;
+    versioncpy[0] -= 1;
+    ret = inflateInit_(&strm, versioncpy, (int)sizeof(z_stream));
                                                 assert(ret == Z_VERSION_ERROR);
     mem_done(&strm, "wrong version");
 

patches/0009-infcover-oob.patch

+From 75690b2683667be5535ac6243438115dc9c40f6a Mon Sep 17 00:00:00 2001
+From: Florian Mayer <fmayer@google.com>
+Date: Wed, 16 Mar 2022 16:38:36 -0700
+Subject: [PATCH] Fix out of bounds in infcover.c.
+
+---
+ test/infcover.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/test/infcover.c b/test/infcover.c
+index 2be01646c..a6d83693c 100644
+--- a/test/infcover.c
++++ b/test/infcover.c
+@@ -373,7 +373,9 @@ local void cover_support(void)
+     mem_setup(&strm);
+     strm.avail_in = 0;
+     strm.next_in = Z_NULL;
+-    ret = inflateInit_(&strm, ZLIB_VERSION - 1, (int)sizeof(z_stream));
++    char versioncpy[] = ZLIB_VERSION;
++    versioncpy[0] -= 1;
++    ret = inflateInit_(&strm, versioncpy, (int)sizeof(z_stream));
+                                                 assert(ret == Z_VERSION_ERROR);
+     mem_done(&strm, "wrong version");
+