bk commit into 4.1 tree (cmiller:1.2706) BUG#33841

[Chad MILLER]

Below is the list of changes that have just been committed into a local
4.1 repository of cmiller. When cmiller does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2008-01-25 10:53:21-05:00, cmiller@stripped +1 -0
  Bug#33841: mysql client crashes when returning results for long-\
  	running queries
  
  Bug#33976: buffer overflow of variable time_buff in function com_go()
  
  An internal buffer was too short.  Overextending could smash the 
  stack on some architectures and cause SEGVs.  This is not a problem
  that could be exploited to run arbitrary code.
  
  To fix, I expanded one buffer to cover all the size that could be
  written to (we know the abolute max).

  client/mysql.cc@stripped, 2008-01-25 10:53:21-05:00, cmiller@stripped +15 -4
    Bump up the max size of the time-elapsed buffer displayed at the end
    of queries.

diff -Nrup a/client/mysql.cc b/client/mysql.cc
--- a/client/mysql.cc	2006-11-02 07:24:58 -05:00
+++ b/client/mysql.cc	2008-01-25 10:53:21 -05:00
@@ -1,4 +1,4 @@
-/* Copyright (C) 2000-2003 MySQL AB
+/* Copyright (C) 2000-2008 MySQL AB
 
    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
@@ -729,7 +729,7 @@ static void usage(int version)
   if (version)
     return;
   printf("\
-Copyright (C) 2002 MySQL AB\n\
+Copyright (C) 2000-2008 MySQL AB\n\
 This software comes with ABSOLUTELY NO WARRANTY. This is free software,\n\
 and you are welcome to modify and redistribute it under the GPL license\n");
   printf("Usage: %s [OPTIONS] [database]\n", my_progname);
@@ -1910,7 +1910,8 @@ com_charset(String *buffer __attribute__
 static int
 com_go(String *buffer,char *line __attribute__((unused)))
 {
-  char		buff[200], time_buff[32], *pos;
+  char		buff[200]; /* about 110 chars used so far */
+  char		time_buff[52+3+1]; /* time max + space&parens + NUL */
   MYSQL_RES	*result;
   ulong		timer, warnings;
   uint		error= 0;
@@ -1973,6 +1974,8 @@ com_go(String *buffer,char *line __attri
 
   do
   {
+    char *pos;
+
     if (quick)
     {
       if (!(result=mysql_use_result(&mysql)) &&
mysql_field_count(&mysql))
@@ -1988,7 +1991,9 @@ com_go(String *buffer,char *line __attri
     if (verbose >= 3 || !opt_silent)
       mysql_end_timer(timer,time_buff);
     else
-      time_buff[0]=0;
+      time_buff[0]= '\0';
+
+    /* Every branch must truncate  buff . */
     if (result)
     {
       if (!mysql_num_rows(result) && ! quick)
@@ -2045,6 +2050,7 @@ com_go(String *buffer,char *line __attri
       fflush(stdout);
     mysql_free_result(result);
   } while (!(err= mysql_next_result(&mysql)));
+
   if (err >= 1)
     error= put_error(&mysql);
 
@@ -3275,6 +3281,11 @@ static ulong start_timer(void)
 }
 
 
+/** 
+  Write as many as 52+1 bytes to buff, in the form of a legible duration of time.
+
+  len("4294967296 days, 23 hours, 59 minutes, 60.00 seconds")  ->  52
+*/
 static void nice_time(double sec,char *buff,bool part_second)
 {
   ulong tmp;