1 files changed, 36 insertions, 0 deletions
diff --git a/backport-Suppress-MSAN-detections-in-deflate-slide_hash.patch b/backport-Suppress-MSAN-detections-in-deflate-slide_hash.patch
new file mode 100644
index 0000000..449a9e3
--- /dev/null
+++ b/backport-Suppress-MSAN-detections-in-deflate-slide_hash.patch
@@ -0,0 +1,36 @@
+From 981ee7570ad98a3cf1ae74d737e2ee619ed79171 Mon Sep 17 00:00:00 2001
+From: Andrzej Hunt <andrzej@ahunt.org>
+Date: Fri, 4 Jun 2021 18:25:19 +0200
+Subject: [PATCH] Suppress MSAN detections in deflate's slide_hash().
+
+slide_hash() knowingly reads potentially uninitialized memory, see
+comment lower down about prev[n] potentially being garbage. In
+this case, the result is never used.
+
+Reference:https://github.com/madler/zlib/commit/981ee7570ad98a3cf1ae74d737e2ee619ed79171
+Conflict:NA
+---
+ deflate.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/deflate.c b/deflate.c
+index 5410497..8088083 100644
+--- a/deflate.c
++++ b/deflate.c
+@@ -209,6 +209,13 @@ local const config configuration_table[10] = {
+  * bit values at the expense of memory usage). We slide even when level == 0 to
+  * keep the hash table consistent if we switch back to level > 0 later.
+  */
++
++#if defined(__has_feature)
++#  if __has_feature(memory_sanitizer)
++     __attribute__((no_sanitize("memory")))
++#  endif
++#endif
++
+ local void slide_hash(s)
+     deflate_state *s;
+ {
+-- 
+2.27.0
+