MDEV-20377: Make WITH_MSAN more usable

MemorySanitizer (clang -fsanitize=memory) requires that all code
be compiled with instrumentation enabled. The only exception is the
C runtime library. Failure to use instrumented libraries will cause
bogus messages about memory being uninitialized.

In WITH_MSAN builds, we must avoid calling getservbyname(),
because even though it is a standard library function, it is
not instrumented, not even in clang 10.

Note: Before MariaDB Server 10.5, ./mtr will typically fail
due to the old PCRE library, which was updated in MDEV-14024.

The following cmake options were tested on 10.5
in commit 94d0bb4dbeb28a94d1f87fdd55f4297ff3df0157:

cmake \
-DCMAKE_C_FLAGS='-march=native -O2' \
-DCMAKE_CXX_FLAGS='-stdlib=libc++ -march=native -O2' \
-DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug \
-DWITH_INNODB_{BZIP2,LZ4,LZMA,LZO,SNAPPY}=OFF \
-DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO \
-DWITH_SAFEMALLOC=OFF \
-DWITH_{ZLIB,SSL,PCRE}=bundled \
-DHAVE_LIBAIO_H=0 \
-DWITH_MSAN=ON

MEM_MAKE_DEFINED(): An alias for VALGRIND_MAKE_MEM_DEFINED()
and __msan_unpoison().

MEM_GET_VBITS(), MEM_SET_VBITS(): Aliases for
VALGRIND_GET_VBITS(), VALGRIND_SET_VBITS(), __msan_copy_shadow().

InnoDB: Replace the UNIV_MEM_ macros with corresponding MEM_ macros.

ut_crc32_8_hw(), ut_crc32_64_low_hw(): Use the compiler built-in
functions instead of inline assembler when building WITH_MSAN.
This will require at least -msse4.2 when building for IA-32 or AMD64.
The inline assembler would not be instrumented, and would thus cause
bogus failures.

1 files changed, 18 insertions, 23 deletions

diff --git a/storage/innobase/buf/buf0buddy.cc b/storage/innobase/buf/buf0buddy.cc
index 0863facad52..a36fc30db9b 100644
--- a/storage/innobase/buf/buf0buddy.cc
+++ b/storage/innobase/buf/buf0buddy.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 2006, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2018, 2019, MariaDB Corporation.
+Copyright (c) 2018, 2020, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -85,7 +85,6 @@ enum buf_buddy_state_t {
 				are in use */
 };
 
-#ifdef UNIV_DEBUG_VALGRIND
 /**********************************************************************//**
 Invalidate memory area that we won't access while page is free */
 UNIV_INLINE
@@ -95,15 +94,11 @@ buf_buddy_mem_invalid(
 	buf_buddy_free_t*	buf,	/*!< in: block to check */
 	ulint			i)	/*!< in: index of zip_free[] */
 {
-	const size_t	size	= BUF_BUDDY_LOW << i;
-	ut_ad(i <= BUF_BUDDY_SIZES);
+  ut_ad(i <= BUF_BUDDY_SIZES);
 
-	UNIV_MEM_ASSERT_W(buf, size);
-	UNIV_MEM_INVALID(buf, size);
+  MEM_CHECK_ADDRESSABLE(buf, BUF_BUDDY_LOW << i);
+  MEM_UNDEFINED(buf, BUF_BUDDY_LOW << i);
 }
-#else /* UNIV_DEBUG_VALGRIND */
-# define buf_buddy_mem_invalid(buf, i) ut_ad((i) <= BUF_BUDDY_SIZES)
-#endif /* UNIV_DEBUG_VALGRIND */
 
 /**********************************************************************//**
 Check if a buddy is stamped free.
@@ -361,11 +356,10 @@ buf_buddy_alloc_zip(
 
 	if (buf) {
 		/* Trash the page other than the BUF_BUDDY_STAMP_NONFREE. */
-		UNIV_MEM_TRASH((void*) buf, ~i, BUF_BUDDY_STAMP_OFFSET);
-		UNIV_MEM_TRASH(BUF_BUDDY_STAMP_OFFSET + 4
-			       + buf->stamp.bytes, ~i,
-			       (BUF_BUDDY_LOW << i)
-			       - (BUF_BUDDY_STAMP_OFFSET + 4));
+		MEM_UNDEFINED(buf, BUF_BUDDY_STAMP_OFFSET);
+		MEM_UNDEFINED(BUF_BUDDY_STAMP_OFFSET + 4 + buf->stamp.bytes,
+			      (BUF_BUDDY_LOW << i)
+			      - (BUF_BUDDY_STAMP_OFFSET + 4));
 		ut_ad(mach_read_from_4(buf->stamp.bytes
 				       + BUF_BUDDY_STAMP_OFFSET)
 		      == BUF_BUDDY_STAMP_NONFREE);
@@ -402,8 +396,10 @@ buf_buddy_block_free(
 	ut_d(bpage->in_zip_hash = FALSE);
 	HASH_DELETE(buf_page_t, hash, buf_pool->zip_hash, fold, bpage);
 
-	ut_d(memset(buf, 0, UNIV_PAGE_SIZE));
-	UNIV_MEM_INVALID(buf, UNIV_PAGE_SIZE);
+	ut_d(memset(buf, 0, srv_page_size));
+#ifdef HAVE_valgrind_or_MSAN
+	MEM_UNDEFINED(buf, srv_page_size);
+#endif /* HAVE_valgrind_or_MSAN */
 
 	block = (buf_block_t*) bpage;
 	buf_page_mutex_enter(block);
@@ -559,17 +555,16 @@ buf_buddy_relocate(
 	ut_ad(!ut_align_offset(src, size));
 	ut_ad(!ut_align_offset(dst, size));
 	ut_ad(i >= buf_buddy_get_slot(UNIV_ZIP_SIZE_MIN));
-	UNIV_MEM_ASSERT_W(dst, size);
+	MEM_CHECK_ADDRESSABLE(dst, size);
 
 	space	= mach_read_from_4((const byte*) src
 				   + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID);
 	offset	= mach_read_from_4((const byte*) src
 				   + FIL_PAGE_OFFSET);
 
-	/* Suppress Valgrind warnings about conditional jump
-	on uninitialized value. */
-	UNIV_MEM_VALID(&space, sizeof space);
-	UNIV_MEM_VALID(&offset, sizeof offset);
+	/* Suppress Valgrind or MSAN warnings. */
+	MEM_MAKE_DEFINED(&space, sizeof space);
+	MEM_MAKE_DEFINED(&offset, sizeof offset);
 
 	ut_ad(space != BUF_BUDDY_STAMP_FREE);
 
@@ -631,7 +626,7 @@ buf_buddy_relocate(
 
 	/* The block must have been allocated, but it may
 	contain uninitialized data. */
-	UNIV_MEM_ASSERT_W(src, size);
+	MEM_CHECK_ADDRESSABLE(src, size);
 
 	BPageMutex*	block_mutex = buf_page_get_mutex(bpage);
 
@@ -686,7 +681,7 @@ buf_buddy_free_low(
 
 	buf_pool->buddy_stat[i].used--;
 recombine:
-	UNIV_MEM_ALLOC(buf, BUF_BUDDY_LOW << i);
+	MEM_UNDEFINED(buf, BUF_BUDDY_LOW << i);
 
 	if (i == BUF_BUDDY_SIZES) {
 		buf_buddy_block_free(buf_pool, buf);