Re: A Famous Security Bug

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From	Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups	comp.lang.c
Subject	Re: A Famous Security Bug
Date	Wed, 20 Mar 2024 14:23:52 -0700
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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
> scott@slp53.sl.home (Scott Lurndal) writes:
>> Kaz Kylheku <433-929-6894@kylheku.com> writes:
>>>On 2024-03-20, Stefan Ram <ram@zedat.fu-berlin.de> wrote:
>>>>   A "famous security bug":
>>>>
>>>> void f( void )
>>>> { char buffer[ MAX ];
>>>>   /* . . . */
>>>>   memset( buffer, 0, sizeof( buffer )); }
>>>>
>>>>   . Can you see what the bug is?
>>>
>>>I don't know about "the bug", but conditions can be identified under
>>>which that would have a problem executing, like MAX being in excess
>>>of available automatic storage.
>>
>> Perhaps Stephan is under the mistaken assumption that
>> 'buffer' devolves to a type of 'char *' when used
>> with the sizeof operator.
>
> That was my first thought, but I think the idea (not clearly stated) is
> that the /* . . . */ code stores sensitive information in buffer, and
> the memset call is intended to clobber that information, but may be
> elided since buffer is not explicitly used later.  A malicious process
> with access to the program's memory might be able to read that
> information after f() has returned.

And I should acknowledge that Kaz mentioned that before I did.

> C23 adds memset_explicit() for this purpose.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */

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Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-20 18:54 +0000
  Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-20 19:38 +0000
    Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-20 14:20 -0700
      Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-20 14:23 -0700
  Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-21 16:13 +0100
    Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-21 17:41 +0000
      Re: A Famous Security Bug "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-03-21 12:37 -0700
        Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-21 20:21 +0000
          Re: A Famous Security Bug "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-03-21 14:31 -0700
            Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-21 23:19 +0000
              Re: A Famous Security Bug "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-03-21 17:38 -0700
                Re: A Famous Security Bug "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-03-22 12:39 -0700
      Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-21 13:46 -0700
        Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 15:50 +0000
          Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-22 09:31 -0700
            Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 17:20 +0000
              Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 13:38 -0400
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 19:27 +0000
              Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 19:13 +0100
              Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-22 11:21 -0700
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 19:43 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-23 16:36 +0100
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-23 16:07 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-23 18:58 +0100
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-24 01:23 +0000
                Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-23 12:51 -0400
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-24 05:50 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 14:21 +0100
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-24 16:02 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 17:27 +0100
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-27 21:06 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-28 19:07 +0100
                Re: A Famous Security Bug "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-03-24 12:45 -0700
          Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 13:05 -0400
          Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 18:42 +0100
            Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 18:55 +0000
              Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 21:26 +0100
        Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 12:35 -0400
          Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 17:28 +0000
            Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 13:38 -0400
      Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 13:51 +0100
  Re: A Famous Security Bug Anton Shepelev <anton.txt@gmail.moc> - 2024-03-21 21:13 +0300
    Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-21 12:42 -0700
    Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-21 20:21 +0000
      Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 14:38 +0100
        Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-22 15:33 +0000
          Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 13:15 -0400
          Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-22 18:50 +0100
            Re: A Famous Security Bug Richard Kettlewell <invalid@invalid.invalid> - 2024-03-23 09:20 +0000
              Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-23 16:06 +0000
              Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-23 17:08 +0100
                Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-23 16:56 +0000
              Re: A Famous Security Bug Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-03-24 09:45 -0700
                Re: A Famous Security Bug Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-03-24 17:53 +0000
      Re: A Famous Security Bug Anton Shepelev <anton.txt@g{oogle}mail.com> - 2024-03-28 12:23 +0300
        Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-28 14:12 +0000
    Re: A Famous Security Bug Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-03-22 07:50 -0700
    Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-22 13:14 -0400
      Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-22 21:41 +0000
        Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-22 16:30 -0700
          Re: A Famous Security Bug Kaz Kylheku <433-929-6894@kylheku.com> - 2024-03-23 00:09 +0000
            Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-23 17:25 +0100
              Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-23 16:51 +0000
              Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-23 19:58 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 14:42 +0100
        Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-23 03:26 -0400
          Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-23 11:26 +0000
            Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-23 17:51 +0100
              Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-23 21:21 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 15:52 +0100
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-24 19:56 +0000
                Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-24 13:49 -0700
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 23:38 +0100
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 01:42 +0300
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 09:37 +0100
                Re: A Famous Security Bug Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-03-25 08:54 -0700
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-24 23:07 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 01:39 +0200
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-25 02:12 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 09:58 +0100
                Re: A Famous Security Bug Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-03-25 13:26 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 15:43 +0200
                Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-25 17:21 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 09:53 +0100
                Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-25 17:24 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-24 23:43 +0100
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 13:16 +0200
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 13:26 +0100
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 15:11 +0200
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 16:30 +0100
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-25 16:39 +0000
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-25 16:06 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 18:51 +0200
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-25 18:10 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 21:01 +0100
                Re: A Famous Security Bug scott@slp53.sl.home (Scott Lurndal) - 2024-03-25 20:28 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 23:05 +0200
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-25 21:25 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-26 01:31 +0200
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-26 00:34 +0000
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 19:07 +0100
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-24 18:53 +0300
                Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-24 18:58 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 13:04 +0200
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-25 13:24 +0200
                Re: A Famous Security Bug David Brown <david.brown@hesbynett.no> - 2024-03-25 16:17 +0100
                Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-28 06:14 -0400
            Re: A Famous Security Bug Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-03-23 11:44 -0700
            Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-24 17:22 +0300
            Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-24 17:26 +0300
              Re: A Famous Security Bug bart <bc@freeuk.com> - 2024-03-24 19:12 +0000
                Re: A Famous Security Bug Michael S <already5chosen@yahoo.com> - 2024-03-24 22:33 +0300
            Re: A Famous Security Bug James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-03-28 05:52 -0400

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