From ac334617a9f20b79f5e554135dca15a4c8144f49 Mon Sep 17 00:00:00 2001
From: Antony Polukhin <antoshkka@gmail.com>
Date: Tue, 6 Jun 2023 18:09:27 +0300
Subject: [PATCH 1/2] Workaround false positive warning of MSAN in eng_rdrand.c
---
crypto/engine/eng_rdrand.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/crypto/engine/eng_rdrand.c b/crypto/engine/eng_rdrand.c
index f46a5145974e..88f2fa20bc3e 100644
--- a/crypto/engine/eng_rdrand.c
+++ b/crypto/engine/eng_rdrand.c
@@ -32,6 +32,16 @@ static int get_random_bytes(unsigned char *buf, int num)
return 0;
}
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+ /*
+ * MemorySanitizer fails to understand asm and produces false positive
+ * use-of-uninitialized-value warnings without memset.
+ */
+ memset(buf, 0, num);
+#endif
+#endif
+
return (size_t)num == OPENSSL_ia32_rdrand_bytes(buf, (size_t)num);
}
From 7096737ce9e2fdc5a1c18e34020c613c4074778c Mon Sep 17 00:00:00 2001
From: Antony Polukhin <antoshkka@gmail.com>
Date: Tue, 6 Jun 2023 20:07:23 +0300
Subject: [PATCH 2/2] Review fixes
---
crypto/engine/eng_rdrand.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/crypto/engine/eng_rdrand.c b/crypto/engine/eng_rdrand.c
index 88f2fa20bc3e..a18a772fb364 100644
--- a/crypto/engine/eng_rdrand.c
+++ b/crypto/engine/eng_rdrand.c
@@ -20,6 +20,12 @@
#include <openssl/err.h>
#include <openssl/crypto.h>
+#if defined(__has_feature)
+# if __has_feature(memory_sanitizer)
+# include <sanitizer/msan_interface.h>
+# endif
+#endif
+
#if (defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
defined(__x86_64) || defined(__x86_64__) || \
defined(_M_AMD64) || defined (_M_X64)) && defined(OPENSSL_CPUID_OBJ)
@@ -32,15 +38,15 @@ static int get_random_bytes(unsigned char *buf, int num)
return 0;
}
-#if defined(__has_feature)
-#if __has_feature(memory_sanitizer)
+# if defined(__has_feature)
+# if __has_feature(memory_sanitizer)
/*
* MemorySanitizer fails to understand asm and produces false positive
- * use-of-uninitialized-value warnings without memset.
+ * use-of-uninitialized-value warnings.
*/
- memset(buf, 0, num);
-#endif
-#endif
+ __msan_unpoison(buf, num);
+# endif
+# endif
return (size_t)num == OPENSSL_ia32_rdrand_bytes(buf, (size_t)num);
}