MDEV-37019 MSAN_STAT_WORKAROUND macro remove

MSAN has been updated since 2022 when this macro was added
and as such the working around MSAN's deficient understanding
of the fstat/stat syscall behaviour at the time is no longer
required.

As an effective no-op a straight removal is sufficient.

Author: grooverdan

extra/mariabackup/fil_cur.cc

@@ -186,7 +186,6 @@ xb_fil_cur_open(
 	}
 #else
 	err = fstat(cursor->file.m_file, &cursor->statinfo);
-	MSAN_STAT_WORKAROUND(&cursor->statinfo);
 #endif
 	if (max_file_size < (ulonglong)cursor->statinfo.st_size) {
 		cursor->statinfo.st_size = (ulonglong)max_file_size;

extra/mariabackup/xtrabackup.cc

@@ -4160,7 +4160,6 @@ os_file_readdir_next_file(
 		return(-1);
 	}
 
-	MSAN_STAT_WORKAROUND(&statinfo);
 	info->size = statinfo.st_size;
 
 	if (S_ISDIR(statinfo.st_mode)) {

include/my_valgrind.h

@@ -37,11 +37,6 @@
 # define MEM_GET_VBITS(a,b,len) __msan_copy_shadow(b,a,len)
 # define MEM_SET_VBITS(a,b,len) __msan_copy_shadow(a,b,len)
 # define REDZONE_SIZE 8
-# ifdef __linux__
-#  define MSAN_STAT_WORKAROUND(st) MEM_MAKE_DEFINED(st, sizeof(*st))
-# else
-#  define MSAN_STAT_WORKAROUND(st) ((void) 0)
-# endif
 #elif defined(HAVE_VALGRIND_MEMCHECK_H) && defined(HAVE_valgrind)
 # include <valgrind/memcheck.h>
 # define HAVE_MEM_CHECK
@@ -54,7 +49,6 @@
 # define MEM_GET_VBITS(a,b,len) VALGRIND_GET_VBITS(a,b,len)
 # define MEM_SET_VBITS(a,b,len) VALGRIND_SET_VBITS(a,b,len)
 # define REDZONE_SIZE 8
-# define MSAN_STAT_WORKAROUND(st) ((void) 0)
 #elif defined(__SANITIZE_ADDRESS__) && (!defined(_MSC_VER) || defined (__clang__))
 # include <sanitizer/asan_interface.h>
 /* How to do manual poisoning:
@@ -68,7 +62,6 @@
 # define MEM_CHECK_DEFINED(a,len) ((void) 0)
 # define MEM_GET_VBITS(a,b,len) ((void) 0)
 # define MEM_SET_VBITS(a,b,len) ((void) 0)
-# define MSAN_STAT_WORKAROUND(st) ((void) 0)
 # define REDZONE_SIZE 8
 #else
 # define MEM_UNDEFINED(a,len) ((void) 0)
@@ -80,7 +73,6 @@
 # define MEM_GET_VBITS(a,b,len) ((void) 0)
 # define MEM_SET_VBITS(a,b,len) ((void) 0)
 # define REDZONE_SIZE 0
-# define MSAN_STAT_WORKAROUND(st) ((void) 0)
 #endif /* __has_feature(memory_sanitizer) */
 
 #ifdef TRASH_FREED_MEMORY

mysys/my_lib.c

@@ -334,13 +334,6 @@ int my_fstat(File Filedes, MY_STAT *stat_area,
   DBUG_PRINT("my",("fd: %d  MyFlags: %lu", Filedes, MyFlags));
 #ifdef _WIN32
   DBUG_RETURN(my_win_fstat(Filedes, stat_area));
-#elif defined HAVE_valgrind
-  {
-    int s= fstat(Filedes, stat_area);
-    if (!s)
-      MSAN_STAT_WORKAROUND(stat_area);
-    DBUG_RETURN(s);
-  }
 #else
   DBUG_RETURN(fstat(Filedes, (struct stat *) stat_area));
 #endif
@@ -361,7 +354,6 @@ MY_STAT *my_stat(const char *path, MY_STAT *stat_area, myf my_flags)
 #ifndef _WIN32
   if (!stat((char *) path, (struct stat *) stat_area))
   {
-    MSAN_STAT_WORKAROUND(stat_area);
     DBUG_RETURN(stat_area);
   }
 #else

mysys/my_symlink.c

@@ -115,7 +115,6 @@ int my_is_symlink(const char *filename __attribute__((unused)))
   struct stat stat_buff;
   if (lstat(filename, &stat_buff))
     return 0;
-  MSAN_STAT_WORKAROUND(&stat_buff);
   return !!S_ISLNK(stat_buff.st_mode);
 #elif defined (_WIN32)
   DWORD dwAttr = GetFileAttributes(filename);

sql/datadict.cc

@@ -162,8 +162,6 @@ Table_type dd_frm_type(THD *thd, char *path, LEX_CSTRING *engine_name,
     if (mysql_file_fstat(file, &state, MYF(MY_WME)))
       goto err;
 
-    MSAN_STAT_WORKAROUND(&state);
-
     if (mysql_file_seek(file, 0, SEEK_SET, MYF(MY_WME)))
       goto err;
 

sql/discover.cc

@@ -72,7 +72,7 @@ int readfrm(const char *name, const uchar **frmdata, size_t *len)
   error= 2;
   if (mysql_file_fstat(file, &state, MYF(0)))
     goto err;
-  MSAN_STAT_WORKAROUND(&state);
+
   read_len= (size_t)MY_MIN(FRM_MAX_SIZE, state.st_size); // safety
 
   // Read whole frm file

sql/parse_file.cc

@@ -465,8 +465,6 @@ sql_parse_prepare(const LEX_CSTRING *file_name, MEM_ROOT *mem_root,
     DBUG_RETURN(0);
   }
 
-  MSAN_STAT_WORKAROUND(&stat_info);
-
   if (stat_info.st_size > INT_MAX-1)
   {
     my_error(ER_FPARSER_TOO_BIG_FILE, MYF(0), file_name->str);

storage/innobase/log/log0log.cc

@@ -284,11 +284,9 @@ static void *log_mmap(os_file_t file,
     struct stat st;
     if (!fstat(file, &st))
     {
-      MSAN_STAT_WORKAROUND(&st);
       const auto st_dev= st.st_dev;
       if (!stat("/dev/shm", &st))
       {
-        MSAN_STAT_WORKAROUND(&st);
         is_pmem= st.st_dev == st_dev;
         if (!is_pmem)
           return ptr; /* MAP_FAILED */

storage/innobase/os/os0file.cc

@@ -865,7 +865,6 @@ os_file_status_posix(
 
 	if (!ret) {
 		/* file exists, everything OK */
-		MSAN_STAT_WORKAROUND(&statinfo);
 	} else if (errno == ENOENT || errno == ENOTDIR || errno == ENAMETOOLONG) {
 		/* file does not exist */
 		return(true);
@@ -1039,7 +1038,6 @@ static ATTRIBUTE_COLD void os_file_log_buffered()
 /** @return whether the log file may work with unbuffered I/O. */
 static ATTRIBUTE_COLD bool os_file_log_maybe_unbuffered(const struct stat &st)
 {
-  MSAN_STAT_WORKAROUND(&st);
   char b[20 + sizeof "/sys/dev/block/" ":" "/../queue/physical_block_size"];
   if (snprintf(b, sizeof b, "/sys/dev/block/%u:%u/queue/physical_block_size",
                major(st.st_dev), minor(st.st_dev)) >=
@@ -1443,7 +1441,6 @@ os_file_size_t os_file_get_size(const char *filename) noexcept
 	int	ret = stat(filename, &s);
 
 	if (ret == 0) {
-		MSAN_STAT_WORKAROUND(&s);
 		file_size.m_total_size = s.st_size;
 		/* st_blocks is in 512 byte sized blocks */
 		file_size.m_alloc_size = s.st_blocks * 512;
@@ -1488,8 +1485,6 @@ os_file_get_status_posix(
 		return(DB_FAIL);
 	}
 
-	MSAN_STAT_WORKAROUND(statinfo);
-
 	switch (statinfo->st_mode & S_IFMT) {
 	case S_IFDIR:
 		stat_info->type = OS_FILE_TYPE_DIR;
@@ -3754,7 +3749,6 @@ void fil_node_t::find_metadata(IF_WIN(,bool create)) noexcept
   struct stat statbuf;
   if (!fstat(file, &statbuf))
   {
-    MSAN_STAT_WORKAROUND(&statbuf);
     block_size= statbuf.st_blksize;
 # ifdef __linux__
     on_ssd= fil_system.is_ssd(statbuf.st_dev);