MySQL Bugs: #20145: perror segfault when call it with error nr

Bug #20145	perror segfault when call it with error nr
Submitted:	30 May 2006 11:09	Modified:	15 Aug 2006 3:07
Reporter:	Markus Heinze	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Command-line Clients	Severity:	S3 (Non-critical)
Version:	5.0.21	OS:	Solaris (Solaris 8)
Assigned to:	Magnus Blåudd	CPU Architecture:	Any

Description:
When built from source the tool extra/perror it segfaults if i run ./perror <errornr>.

gcc -version:
gcc (GCC) 3.3.2
Copyright (C) 2003 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

builded with:
#!/bin/bash

. platform.sh

export CXX=gcc
#export CFLAGS="-O3 -DUSE_OLD_FUNCTIONS"
export CFLAGS="-DUSE_OLD_FUNCTIONS"
export CXXFLAGS=$CFLAGS
#export CXXFLAGS="$CFLAGS -felide-constructors -fno-exceptions -fno-rtti"
#echo $CXXFLAGS
cd mysql

./configure \
--prefix=/usr/local \
--sysconfdir=/etc \
--localstatedir=/JobsAdverts/SqlServer/var \
--enable-thread-safe-client \
--enable-assembler \
--enable-static \
--with-raid \
--with-mysql-user=mysql \
--without-debug \
--without-docs \
--without-bench \
--with-extra-charsets=complex \
--with-innodb \

$MAKE -j 4 &&
cd mysql-test && ./mysql-test-run --force

cd ..

How to repeat:
run perror with errnr e.g. ./perror 150

Suggested fix:
I have outcommented the NETWARE initialization and it works for me now.
I should be better written between  #ifdef /  #endif  tags.

--- perror.c.orig       Wed Apr 26 20:31:09 2006
+++ perror.c    Wed May  3 13:58:29 2006
@@ -218,10 +218,10 @@
       On some system, like NETWARE, strerror(unknown_error) returns a
       string 'Unknown Error'.  To avoid printing it we try to find the
       error string by asking for an impossible big error message.
-    */
+    
     msg= strerror(10000);
 
-    /*
+   
       Allocate a buffer for unknown_error since strerror always returns
       the same pointer on some platforms such as Windows
     */

Thank you for a problem report. Can you try to repeat with MySQL's binaries? 

The problem is that we do not really use gcc for builds on platforms with "native" C compilers, so gcc environment on any our Solaris boxes is not "clear enough" to repeat this (although, I'll try to build with gcc if official binaries will not demonstrate the behaviour described). I was also unable to repeat this on Linux with gcc 3.3.5, so it can be a compiler-related problem as well.

I have tried the binary version (mysql-standard-5.0.22-solaris8-sparc-64bit.pkg.gz) for Solaris 8 and get the same problem.

./perror 150
Segmentation Fault (core dumped)

./perror -v
./perror Ver 2.10, for sun-solaris2.8 (sparc)
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL license

Print a description for a system error code or an error code from
a MyISAM/ISAM/BDB table handler.
If you want to get the error for a negative error code, you should use
-- before the first error code to tell perror that there was no more options.

Usage: ./perror [OPTIONS] [ERRORCODE [ERRORCODE...]]
  -?, --help          Displays this help and exits.
  -I, --info          Synonym for --help.
  -s, --silent        Only print the error message.
  -v, --verbose       Print error code and message (default).
  -V, --version       Displays version information and exits.

Variables (--variable-name=value)
and boolean options {FALSE|TRUE}  Value (after reading options)
--------------------------------- -----------------------------
verbose                           TRUE

Verified as reporter described:

mysqldev@sunfire100a:~/sveta/mysql-standard-5.0.22-solaris8-sparc-64bit> uname -a
SunOS sunfire100a 5.8 Generic_117350-25 sun4u sparc SUNW,UltraAX-i2
mysqldev@sunfire100a:~/sveta/mysql-standard-5.0.22-solaris8-sparc-64bit> bin/perror 150
Segmentation Fault (core dumped)
mysqldev@sunfire100a:~/sveta/mysql-standard-5.0.22-solaris8-sparc-64bit> bin/perror -v
bin/perror Ver 2.10, for sun-solaris2.8 (sparc)
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL license

Print a description for a system error code or an error code from
a MyISAM/ISAM/BDB table handler.
If you want to get the error for a negative error code, you should use
-- before the first error code to tell perror that there was no more options.

Usage: bin/perror [OPTIONS] [ERRORCODE [ERRORCODE...]]
  -?, --help          Displays this help and exits.
  -I, --info          Synonym for --help.
  -s, --silent        Only print the error message.
  -v, --verbose       Print error code and message (default).
  -V, --version       Displays version information and exits.

Variables (--variable-name=value)
and boolean options {FALSE|TRUE}  Value (after reading options)
--------------------------------- -----------------------------
verbose                           TRUE

I can not repeat this error on Solaris9 SPARC and Solaris10 x86.

We have duplicate bug #20731

I didn't find this one last time.
 Please ignore the new bug report.
 It's the same bug.

For solaris 8/7/6
strerror
RETURN VALUES
     The strerror() function returns NULL if  errnum  is  out-of-
     range.

For solaris 9/10
RETURN VALUES
     Upon successful completion, strerror() returns a pointer  to
     the  generated  message string. Otherwise, it sets errno and
     returns a pointer to an error message string. It returns the
     string  "Unknown  error"  if  errnum  is  not  a valid error
     number.

That's why you couldn't reproduce it on solaris 9/10.
It's a bug.

BTW, 
It's not safe to have code like below 

 /*
      On some system, like NETWARE, strerror(unknown_error) returns a
      string 'Unknown Error'.  To avoid printing it we try to find the
      error string by asking for an impossible big error message.
    */
    msg= strerror(10000);  
   /* msg could be set to NULL under some platforms
    * then strlen would core .
    */

                                                                       
                                                                        
            
    /*
      Allocate a buffer for unknown_error since strerror always
returns
      the same pointer on some platforms such as Windows
    */
    unknown_error= malloc(strlen(msg)+1);

Suggested fix:
/*
      On some system, like NETWARE, strerror(unknown_error) returns a
      string 'Unknown Error'.  To avoid printing it we try to find the
      error string by asking for an impossible big error message.
    */
    msg= strerror(10000);  
   /* msg could be set to NULL on some platforms
    *  e.g solaris 2.8
    */
     if (NULL==msg)
         msg="Unknown  Error";

                                                                       
                                                                        
            
    /*
      Allocate a buffer for unknown_error since strerror always
returns
      the same pointer on some platforms such as Windows
    */
    unknown_error= malloc(strlen(msg)+1);

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/9505

Pushed to 5.0.25

Noted in 5.0.25 changelog.

perror crashed on Solaris due to NULL return value of strerror()
system call.

Merged into 5.1.12

Noted in 5.1.12 changelog.

There is similar bug #25344