From: Mika Lindqvist <postmaster@raasu.org>
Date: Sun, 20 Sep 2020 01:25:21 +0000 (-0700)
Subject: Fix unsigned integer overflow ASAN error for align_diff in crc_folding.c.
X-Git-Tag: 1.9.9-b1~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=74b374d1c4e3494925b010424416dd3481c2ada7;p=thirdparty%2Fzlib-ng.git

Fix unsigned integer overflow ASAN error for align_diff in crc_folding.c.

  zlib-ng/arch/x86/crc_folding.c:252:31: runtime error: unsigned integer overflow: 0 - 108370614813184 cannot be represented in type 'unsigned long'
---

diff --git a/arch/x86/crc_folding.c b/arch/x86/crc_folding.c
index 8e32d97b6..918bd9468 100644
--- a/arch/x86/crc_folding.c
+++ b/arch/x86/crc_folding.c
@@ -249,7 +249,7 @@ Z_INTERNAL void crc_fold_copy(deflate_state *const s, unsigned char *dst, const
         goto partial;
     }
 
-    algn_diff = ((uintptr_t)0 - (uintptr_t)src) & 0xF;
+    algn_diff = ((uintptr_t)16 - ((uintptr_t)src & 0xF)) & 0xF;
     if (algn_diff) {
         xmm_crc_part = _mm_loadu_si128((__m128i *)src);
         _mm_storeu_si128((__m128i *)dst, xmm_crc_part);