Merge april.(none):/home/svoj/devel/mysql/BUG17917/mysql-4.1

into  april.(none):/home/svoj/devel/mysql/BUG17917/mysql-5.0


sql/mysqld.cc:
  Auto merged
myisam/mi_packrec.c:
  Manual merge.

1 files changed, 11 insertions, 5 deletions

diff --git a/myisam/mi_packrec.c b/myisam/mi_packrec.c
index e242e9d506d..41ab71204c4 100644
--- a/myisam/mi_packrec.c
+++ b/myisam/mi_packrec.c
@@ -1189,24 +1189,30 @@ my_bool _mi_memmap_file(MI_INFO *info)
   MYISAM_SHARE *share=info->s;
   DBUG_ENTER("mi_memmap_file");
 
-  if (!info->s->file_map)
+  if (!share->file_map)
   {
+    my_off_t data_file_length= share->state.state.data_file_length;
+    if (data_file_length > (my_off_t) (~((size_t) 0)) - MEMMAP_EXTRA_MARGIN)
+    {
+      DBUG_PRINT("warning", ("File is too large for mmap"));
+      DBUG_RETURN(0);
+    }
     if (my_seek(info->dfile,0L,MY_SEEK_END,MYF(0)) <
-	share->state.state.data_file_length+MEMMAP_EXTRA_MARGIN)
+        data_file_length + MEMMAP_EXTRA_MARGIN)
     {
       DBUG_PRINT("warning",("File isn't extended for memmap"));
       DBUG_RETURN(0);
     }
     file_map=(byte*)
-      my_mmap(0,(size_t)(share->state.state.data_file_length+MEMMAP_EXTRA_MARGIN),PROT_READ,
-	   MAP_SHARED | MAP_NORESERVE,info->dfile,0L);
+      my_mmap(0, (size_t) (data_file_length + MEMMAP_EXTRA_MARGIN), PROT_READ,
+              MAP_SHARED | MAP_NORESERVE, info->dfile, 0L);
     if (file_map == (byte*) MAP_FAILED)
     {
       DBUG_PRINT("warning",("mmap failed: errno: %d",errno));
       my_errno=errno;
       DBUG_RETURN(0);
     }
-    info->s->file_map=file_map;
+    share->file_map= file_map;
   }
   info->opt_flag|= MEMMAP_USED;
   info->read_record=share->read_record=_mi_read_mempack_record;