bug#719: Crash opening UNC file

bug#719: Crash opening UNC file

[john naegle]

Whenever I try to open a file on a share on another computer, emacs crashes.

For instance, trying to open the file: "\\server\software\file.txt"
causes a crash.  This happens if I use find-file, drag a file onto
emacs, or double click to open a file on a hidden network share.

If I double-escape all the backslashes, I still get the crash, eg:
emacs \\\\server\\software\\file.txt


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
c:/Program Files/emacs-22.2/etc/DEBUG for instructions.

bt full:
--------------------------------------------------------------------------------
Load new symbol table from "/cygdrive/c/Program Files/emacs-22.2/bin/emacs.exe"?
 (y or n) y
Reading symbols from /cygdrive/c/Program Files/emacs-22.2/bin/emacs.exe...done.
Loaded symbols for /cygdrive/c/WINNT/system32/NTDLL.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/ADVAPI32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/KERNEL32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/rpcrt4.dll
Loaded symbols for /cygdrive/c/WINNT/system32/secur32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/comctl32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/GDI32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/USER32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/comdlg32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/SHLWAPI.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/msvcrt.dll
Loaded symbols for /cygdrive/c/WINNT/system32/SHELL32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/mpr.dll
Loaded symbols for /cygdrive/c/WINNT/system32/OLE32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/winmm.dll
Loaded symbols for /cygdrive/c/WINNT/system32/winspool.drv
Loaded symbols for /cygdrive/c/WINNT/system32/MSCTF.DLL
Loaded symbols for /cygdrive/c/Program Files/emacs-22.2/bin/libXpm.dll
Loaded symbols for /cygdrive/c/WINNT/system32/crtdll.dll
Loaded symbols for /cygdrive/c/WINNT/system32/OLEAUT32.DLL
[Switching to thread 3636.0x8d4]
(gdb) bt full
#0  0x77f9193d in ntdll!DbgUiConnectToDbg ()
   from /cygdrive/c/WINNT/system32/NTDLL.DLL
No symbol table info available.
#1  0x7c57fecd in KERNEL32!DebugActiveProcess ()
   from /cygdrive/c/WINNT/system32/KERNEL32.DLL
No symbol table info available.
#2  0x7c57b3bc in lstrcmpiW () from /cygdrive/c/WINNT/system32/KERNEL32.DLL
No symbol table info available.
#3  0x00000000 in ?? ()
No symbol table info available.



In GNU Emacs 22.2.1 (i386-mingw-nt5.0.2195)
 of 2008-03-26 on RELEASE
Windowing system distributor `Microsoft Corp.', version 5.0.2195
configured using `configure --with-gcc (3.4)'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ENU
  locale-coding-system: cp1252
  default-enable-multibyte-characters: t

Major mode: C++/l

Minor modes in effect:
  fast-lock-mode: t
  encoded-kbd-mode: t
  tooltip-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:

Recent messages:
Loading semantic-c...done
File mode specification error: (error "Autoloading failed to define
function semantic-default-c-setup")
Loading vc-svn...done
Loading vc...done
Mark saved where search started
Mark set [2 times]
Making completion list...
Loading eieio-opt...done
Making completion list...
Loading emacsbug...done

Processed: another w32 bug

[Emacs bug Tracking System]

Processing commands for control@emacsbugs.donarmstrong.com:

> reassign 719 emacs,w32
bug#719: Crash opening UNC file
Warning: Unknown package 'w32'
bug reassigned from package `emacs' to `emacs,w32'.

>
End of message, stopping processing here.

Please contact me if you need assistance.

Don Armstrong
(administrator, Emacs bugs database)

bug#724: Processed: another w32 bug

[Eli Zaretskii]

> Date: Thu, 14 Aug 2008 17:50:05 -0700
> From: don@donarmstrong.com (Emacs bug Tracking System)
> Cc: Emacs Bugs <bug-gnu-emacs@gnu.org>, w32 #719 <don@donarmstrong.com>
> 
> Processing commands for control@emacsbugs.donarmstrong.com:
> 
> > reassign 719 emacs,w32
> bug#719: Crash opening UNC file
> Warning: Unknown package 'w32'
> bug reassigned from package `emacs' to `emacs,w32'.

Why, Jason?  This problem is specific to Cygwin, UNC file names work
in the native w32 build.

If we want to distinguish between Cygwin and the rest of Posix
platforms, I suggest to create a new category "cygwin" and assign this
bug to it.

bug#719: Crash opening UNC file

[Eli Zaretskii]

> Date: Thu, 14 Aug 2008 11:00:59 -0400
> From: "john naegle" <john.naegle@gmail.com>
> Cc: 
> 
> Whenever I try to open a file on a share on another computer, emacs crashes.

Thank you for your report.

> For instance, trying to open the file: "\\server\software\file.txt"
> causes a crash.  This happens if I use find-file, drag a file onto
> emacs, or double click to open a file on a hidden network share.
> 
> If I double-escape all the backslashes, I still get the crash, eg:
> emacs \\\\server\\software\\file.txt

Does it work with forward slashes, like this:

   //server/software/file.txt

?

> [Switching to thread 3636.0x8d4]
> (gdb) bt full
> #0  0x77f9193d in ntdll!DbgUiConnectToDbg ()
>    from /cygdrive/c/WINNT/system32/NTDLL.DLL
> No symbol table info available.
> #1  0x7c57fecd in KERNEL32!DebugActiveProcess ()
>    from /cygdrive/c/WINNT/system32/KERNEL32.DLL
> No symbol table info available.
> #2  0x7c57b3bc in lstrcmpiW () from /cygdrive/c/WINNT/system32/KERNEL32.DLL
> No symbol table info available.
> #3  0x00000000 in ?? ()
> No symbol table info available.

This backtrace is not useful.  I think you are in the wrong thread.

Could you please type "info threads" and then switch to each one of
them (with "thread N", where N is the thread number displayed in the
1st column of what "info threads" presents), and find the main thread,
where the backtrace goes up to the `main' function?  That's the
backtrace we want to see.

TIA

bug#719: Crash opening UNC file

[john naegle]

On a hunch, I commented everything out in my .emacs file and tried to
re-open the file.  I was able to open it without a crash, so I
systematically added things back until I could reproduce the crash.
The culprit turned out to be this line: (require 'rails).

Here are the answers to your questions if you want to pursue this
further.  Let me know if you would like my .emacs file.

Trying to open //server/software/file.txt also crashed.

Here is everything I was able to get out of GDB, it didn't seem that
helpful to me:

Let me know if you want me to try anything else.

This debugging session was started by:

#1) Launching C:\Program Files\emacs-22.2\bin\runemacs.exe
#2) find-file \\server\software\file.txt
#3) Emacs crash dialog presented
#4) gdb -p <pid>

$ gdb -p 2616
GNU gdb 6.5.50.20060706-cvs (cygwin-special)
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-cygwin".
Attaching to process 2616

[Switching to thread 2616.0x870]
(gdb) info threads
* 3 thread 2616.0x870  0x77f9193d in ntdll!DbgUiConnectToDbg ()
  2 thread 2616.0x984  0x77e585c7 in USER32!GetMenuItemRect ()
  1 thread 2616.0xaac  0x77e58b53 in WaitMessage ()

(gdb) bt full
#0  0x77f9193d in ntdll!DbgUiConnectToDbg ()
No symbol table info available.
#1  0x7c57fecd in KERNEL32!DebugActiveProcess ()
No symbol table info available.
#2  0x7c57b3bc in lstrcmpiW ()
No symbol table info available.
#3  0x00000000 in ?? ()
No symbol table info available.

(gdb) thread 2
[Switching to thread 2 (thread 2616.0x984)]#0  0x77e585c7 in USER32!GetMenuItemR
ect ()
(gdb) bt full
#0  0x77e585c7 in USER32!GetMenuItemRect ()
No symbol table info available.
#1  0x77e1698f in USER32!GetMessageA ()
No symbol table info available.
#2  0x01139207 in ?? ()
No symbol table info available.

(gdb) thread 1
[Switching to thread 1 (thread 2616.0xaac)]#0  0x77e58b53 in WaitMessage ()
(gdb) bt full
#0  0x77e58b53 in WaitMessage ()
No symbol table info available.
#1  0x77e33630 in USER32!MessageBoxA ()
No symbol table info available.
#2  0x77e44327 in USER32!CheckRadioButton ()
No symbol table info available.
#3  0x001008bc in ?? ()
No symbol table info available.


On Fri, Aug 15, 2008 at 3:55 AM, Eli Zaretskii <eliz@gnu.org> wrote:
>> Date: Thu, 14 Aug 2008 11:00:59 -0400
>> From: "john naegle" <john.naegle@gmail.com>
>> Cc:
>>
>> Whenever I try to open a file on a share on another computer, emacs crashes.
>
> Thank you for your report.
>
>> For instance, trying to open the file: "\\server\software\file.txt"
>> causes a crash.  This happens if I use find-file, drag a file onto
>> emacs, or double click to open a file on a hidden network share.
>>
>> If I double-escape all the backslashes, I still get the crash, eg:
>> emacs \\\\server\\software\\file.txt
>
> Does it work with forward slashes, like this:
>
>   //server/software/file.txt
>
> ?
>
>> [Switching to thread 3636.0x8d4]
>> (gdb) bt full
>> #0  0x77f9193d in ntdll!DbgUiConnectToDbg ()
>>    from /cygdrive/c/WINNT/system32/NTDLL.DLL
>> No symbol table info available.
>> #1  0x7c57fecd in KERNEL32!DebugActiveProcess ()
>>    from /cygdrive/c/WINNT/system32/KERNEL32.DLL
>> No symbol table info available.
>> #2  0x7c57b3bc in lstrcmpiW () from /cygdrive/c/WINNT/system32/KERNEL32.DLL
>> No symbol table info available.
>> #3  0x00000000 in ?? ()
>> No symbol table info available.
>
> This backtrace is not useful.  I think you are in the wrong thread.
>
> Could you please type "info threads" and then switch to each one of
> them (with "thread N", where N is the thread number displayed in the
> 1st column of what "info threads" presents), and find the main thread,
> where the backtrace goes up to the `main' function?  That's the
> backtrace we want to see.
>
> TIA
>

bug#719: Crash opening UNC file

[Eli Zaretskii]

> Date: Fri, 15 Aug 2008 09:20:12 -0400
> From: "john naegle" <john.naegle@gmail.com>
> Cc: 719@emacsbugs.donarmstrong.com, bug-gnu-emacs@gnu.org
> 
> On a hunch, I commented everything out in my .emacs file and tried to
> re-open the file.  I was able to open it without a crash, so I
> systematically added things back until I could reproduce the crash.
> The culprit turned out to be this line: (require 'rails).

What is 'rails?

bug#719: Crash opening UNC file

[john naegle]

Its a minor mode for ruby on rails.

I filed a bug against rails-mode:
http://rubyforge.org/tracker/index.php?func=detail&aid=21573&group_id=1484&atid=5809

There was another bug for this already:
http://rubyforge.org/tracker/index.php?func=detail&aid=21046&group_id=1484&atid=5809

Thanks,
-John

On Fri, Aug 15, 2008 at 1:12 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> Date: Fri, 15 Aug 2008 09:20:12 -0400
>> From: "john naegle" <john.naegle@gmail.com>
>> Cc: 719@emacsbugs.donarmstrong.com, bug-gnu-emacs@gnu.org
>>
>> On a hunch, I commented everything out in my .emacs file and tried to
>> re-open the file.  I was able to open it without a crash, so I
>> systematically added things back until I could reproduce the crash.
>> The culprit turned out to be this line: (require 'rails).
>
> What is 'rails?
>

bug#719: Crash opening UNC file

[Stefan Monnier]

> Its a minor mode for ruby on rails.
> I filed a bug against rails-mode:
> http://rubyforge.org/tracker/index.php?func=detail&aid=21573&group_id=1484&atid=5809

In most cases, if Emacs crashes, it's a bug in the C code of Emacs and
not in Elisp code (bundled or third party).


        Stefan

bug#719: marked as done (Crash opening UNC file)

[Emacs bug Tracking System]

[-- Attachment #1: Type: text/plain, Size: 826 bytes --]


Your message dated Sat, 20 Dec 2008 23:33:41 +0800
with message-id <494D1055.5030508@gnu.org>
and subject line Re: Crash opening UNC file.
has caused the Emacs bug report #719,
regarding Crash opening UNC file
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner@emacsbugs.donarmstrong.com
immediately.)


-- 
719: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=719
Emacs Bug Tracking System
Contact owner@emacsbugs.donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 6830 bytes --]

From: "john naegle" <john.naegle@gmail.com>
To: bug-gnu-emacs@gnu.org
Subject: Crash opening UNC file
Date: Thu, 14 Aug 2008 11:00:59 -0400
Message-ID: <eb5a18c20808140800ob954c8apaadfc4934956807c@mail.gmail.com>

Whenever I try to open a file on a share on another computer, emacs crashes.

For instance, trying to open the file: "\\server\software\file.txt"
causes a crash.  This happens if I use find-file, drag a file onto
emacs, or double click to open a file on a hidden network share.

If I double-escape all the backslashes, I still get the crash, eg:
emacs \\\\server\\software\\file.txt


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
c:/Program Files/emacs-22.2/etc/DEBUG for instructions.

bt full:
--------------------------------------------------------------------------------
Load new symbol table from "/cygdrive/c/Program Files/emacs-22.2/bin/emacs.exe"?
 (y or n) y
Reading symbols from /cygdrive/c/Program Files/emacs-22.2/bin/emacs.exe...done.
Loaded symbols for /cygdrive/c/WINNT/system32/NTDLL.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/ADVAPI32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/KERNEL32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/rpcrt4.dll
Loaded symbols for /cygdrive/c/WINNT/system32/secur32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/comctl32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/GDI32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/USER32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/comdlg32.dll
Loaded symbols for /cygdrive/c/WINNT/system32/SHLWAPI.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/msvcrt.dll
Loaded symbols for /cygdrive/c/WINNT/system32/SHELL32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/mpr.dll
Loaded symbols for /cygdrive/c/WINNT/system32/OLE32.DLL
Loaded symbols for /cygdrive/c/WINNT/system32/winmm.dll
Loaded symbols for /cygdrive/c/WINNT/system32/winspool.drv
Loaded symbols for /cygdrive/c/WINNT/system32/MSCTF.DLL
Loaded symbols for /cygdrive/c/Program Files/emacs-22.2/bin/libXpm.dll
Loaded symbols for /cygdrive/c/WINNT/system32/crtdll.dll
Loaded symbols for /cygdrive/c/WINNT/system32/OLEAUT32.DLL
[Switching to thread 3636.0x8d4]
(gdb) bt full
#0  0x77f9193d in ntdll!DbgUiConnectToDbg ()
   from /cygdrive/c/WINNT/system32/NTDLL.DLL
No symbol table info available.
#1  0x7c57fecd in KERNEL32!DebugActiveProcess ()
   from /cygdrive/c/WINNT/system32/KERNEL32.DLL
No symbol table info available.
#2  0x7c57b3bc in lstrcmpiW () from /cygdrive/c/WINNT/system32/KERNEL32.DLL
No symbol table info available.
#3  0x00000000 in ?? ()
No symbol table info available.



In GNU Emacs 22.2.1 (i386-mingw-nt5.0.2195)
 of 2008-03-26 on RELEASE
Windowing system distributor `Microsoft Corp.', version 5.0.2195
configured using `configure --with-gcc (3.4)'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ENU
  locale-coding-system: cp1252
  default-enable-multibyte-characters: t

Major mode: C++/l

Minor modes in effect:
  fast-lock-mode: t
  encoded-kbd-mode: t
  tooltip-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:

Recent messages:
Loading semantic-c...done
File mode specification error: (error "Autoloading failed to define
function semantic-default-c-setup")
Loading vc-svn...done
Loading vc...done
Mark saved where search started
Mark set [2 times]
Making completion list...
Loading eieio-opt...done
Making completion list...
Loading emacsbug...done




[-- Attachment #3: Type: message/rfc822, Size: 2760 bytes --]

From: Jason Rumney <jasonr@gnu.org>
To: "john naegle" <john.naegle@gmail.com>
Cc: 719-done@emacsbugs.donarmstrong.com
Subject: Re: Crash opening UNC file.
Date: Sat, 20 Dec 2008 23:33:41 +0800
Message-ID: <494D1055.5030508@gnu.org>

This turned out to be a bug in expand-file-name triggered by the project 
file searching code in rails.el.

A simple way to reproduce the bug was:

(expand-file-name "//server/path/../../../")

which caused an assertion failure on Windows.

I have checked in a fix.

bug#724: marked as done (Processed: another w32 bug)

[Emacs bug Tracking System]

[-- Attachment #1: Type: text/plain, Size: 830 bytes --]


Your message dated Sat, 20 Dec 2008 23:33:41 +0800
with message-id <494D1055.5030508@gnu.org>
and subject line Re: Crash opening UNC file.
has caused the Emacs bug report #719,
regarding Processed: another w32 bug
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner@emacsbugs.donarmstrong.com
immediately.)


-- 
719: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=719
Emacs Bug Tracking System
Contact owner@emacsbugs.donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 2556 bytes --]

From: Eli Zaretskii <eliz@gnu.org>
To: bug-gnu-emacs@gnu.org
Cc: jasonr@gnu.org
Subject: Re: Processed: another w32 bug
Date: Fri, 15 Aug 2008 10:48:10 +0300
Message-ID: <uk5eig1mt.fsf@gnu.org>

> Date: Thu, 14 Aug 2008 17:50:05 -0700
> From: don@donarmstrong.com (Emacs bug Tracking System)
> Cc: Emacs Bugs <bug-gnu-emacs@gnu.org>, w32 #719 <don@donarmstrong.com>
> 
> Processing commands for control@emacsbugs.donarmstrong.com:
> 
> > reassign 719 emacs,w32
> bug#719: Crash opening UNC file
> Warning: Unknown package 'w32'
> bug reassigned from package `emacs' to `emacs,w32'.

Why, Jason?  This problem is specific to Cygwin, UNC file names work
in the native w32 build.

If we want to distinguish between Cygwin and the rest of Posix
platforms, I suggest to create a new category "cygwin" and assign this
bug to it.




[-- Attachment #3: Type: message/rfc822, Size: 2760 bytes --]

From: Jason Rumney <jasonr@gnu.org>
To: "john naegle" <john.naegle@gmail.com>
Cc: 719-done@emacsbugs.donarmstrong.com
Subject: Re: Crash opening UNC file.
Date: Sat, 20 Dec 2008 23:33:41 +0800
Message-ID: <494D1055.5030508@gnu.org>

This turned out to be a bug in expand-file-name triggered by the project 
file searching code in rails.el.

A simple way to reproduce the bug was:

(expand-file-name "//server/path/../../../")

which caused an assertion failure on Windows.

I have checked in a fix.