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, 24 insertions, 17 deletions

diff --git a/storage/innobase/row/row0merge.cc b/storage/innobase/row/row0merge.cc
index 5cbfe0e3ddb..3a6d8cea4a8 100644
--- a/storage/innobase/row/row0merge.cc
+++ b/storage/innobase/row/row0merge.cc
@@ -1027,11 +1027,11 @@ row_merge_buf_write(
 	ut_a(b < &block[srv_sort_buf_size]);
 	ut_a(b == &block[0] + buf->total_size);
 	*b++ = 0;
-#ifdef UNIV_DEBUG_VALGRIND
+#ifdef HAVE_valgrind_or_MSAN
 	/* The rest of the block is uninitialized.  Initialize it
 	to avoid bogus warnings. */
 	memset(b, 0xff, &block[srv_sort_buf_size] - b);
-#endif /* UNIV_DEBUG_VALGRIND */
+#endif /* HAVE_valgrind_or_MSAN */
 	DBUG_LOG("ib_merge_sort",
 		 "write " << reinterpret_cast<const void*>(b) << ','
 		 << of->fd << ',' << of->offset << " EOF");
@@ -1425,7 +1425,9 @@ row_merge_write_rec(
 			return(NULL);
 		}
 
-		UNIV_MEM_INVALID(&block[0], srv_sort_buf_size);
+#ifdef HAVE_valgrind_or_MSAN
+		MEM_UNDEFINED(&block[0], srv_sort_buf_size);
+#endif /* HAVE_valgrind_or_MSAN */
 
 		/* Copy the rest. */
 		b = &block[0];
@@ -1466,20 +1468,19 @@ row_merge_write_eof(
 		 ",fd=" << fd << ',' << *foffs);
 
 	*b++ = 0;
-	UNIV_MEM_ASSERT_RW(&block[0], b - &block[0]);
-	UNIV_MEM_ASSERT_W(&block[0], srv_sort_buf_size);
+	MEM_CHECK_DEFINED(&block[0], b - &block[0]);
+	MEM_CHECK_ADDRESSABLE(&block[0], srv_sort_buf_size);
 
-#ifdef UNIV_DEBUG_VALGRIND
-	/* The rest of the block is uninitialized.  Initialize it
-	to avoid bogus warnings. */
-	memset(b, 0xff, &block[srv_sort_buf_size] - b);
-#endif /* UNIV_DEBUG_VALGRIND */
+	/* The rest of the block is uninitialized. Silence warnings. */
+	MEM_MAKE_DEFINED(b, &block[srv_sort_buf_size] - b);
 
 	if (!row_merge_write(fd, (*foffs)++, block, crypt_block, space)) {
 		DBUG_RETURN(NULL);
 	}
 
-	UNIV_MEM_INVALID(&block[0], srv_sort_buf_size);
+#ifdef HAVE_valgrind_or_MSAN
+	MEM_UNDEFINED(&block[0], srv_sort_buf_size);
+#endif
 	DBUG_RETURN(&block[0]);
 }
 
@@ -2550,8 +2551,10 @@ write_buffers:
 						break;
 					}
 
-					UNIV_MEM_INVALID(
+#ifdef HAVE_valgrind_or_MSAN
+					MEM_UNDEFINED(
 						&block[0], srv_sort_buf_size);
+#endif /* HAVE_valgrind_or_MSAN */
 				}
 			}
 			merge_buf[i] = row_merge_buf_empty(buf);
@@ -3034,10 +3037,10 @@ row_merge(
 	ulint		n_run	= 0;
 				/*!< num of runs generated from this merge */
 
-	UNIV_MEM_ASSERT_W(&block[0], 3 * srv_sort_buf_size);
+	MEM_CHECK_ADDRESSABLE(&block[0], 3 * srv_sort_buf_size);
 
 	if (crypt_block) {
-		UNIV_MEM_ASSERT_W(&crypt_block[0], 3 * srv_sort_buf_size);
+		MEM_CHECK_ADDRESSABLE(&crypt_block[0], 3 * srv_sort_buf_size);
 	}
 
 	ut_ad(ihalf < file->offset);
@@ -3058,7 +3061,9 @@ row_merge(
 	foffs0 = 0;
 	foffs1 = ihalf;
 
-	UNIV_MEM_INVALID(run_offset, *num_run * sizeof *run_offset);
+#ifdef HAVE_valgrind_or_MSAN
+	MEM_UNDEFINED(run_offset, *num_run * sizeof *run_offset);
+#endif /* HAVE_valgrind_or_MSAN */
 
 	for (; foffs0 < ihalf && foffs1 < file->offset; foffs0++, foffs1++) {
 
@@ -3139,7 +3144,9 @@ row_merge(
 	*tmpfd = file->fd;
 	*file = of;
 
-	UNIV_MEM_INVALID(&block[0], 3 * srv_sort_buf_size);
+#ifdef HAVE_valgrind_or_MSAN
+	MEM_UNDEFINED(&block[0], 3 * srv_sort_buf_size);
+#endif /* HAVE_valgrind_or_MSAN */
 
 	return(DB_SUCCESS);
 }
@@ -3252,7 +3259,7 @@ row_merge_sort(
 			break;
 		}
 
-		UNIV_MEM_ASSERT_RW(run_offset, num_runs * sizeof *run_offset);
+		MEM_CHECK_DEFINED(run_offset, num_runs * sizeof *run_offset);
 	} while (num_runs > 1);
 
 	ut_free(run_offset);