[Bug c/105357] dereferenced ptr on param stack gets over written

[vwebber at msn dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105357

--- Comment #4 from vwebber <vwebber at msn dot com> ---
BTW, what happens in the rare occurrence of a bug report being found valid.  

Regards, 

Victor Webber
V&T: 408-221-8467 
V:      805-924-1953
vwebber@msn.com


-----Original Message-----
From: Victor Webber 
Sent: Saturday, April 23, 2022 2:04 AM
To: pinskia at gcc dot gnu.org <gcc-bugzilla@gcc.gnu.org>
Subject: RE: [Bug c/105357] dereferenced ptr on param stack gets over written

Thank you for the comments. 

However, the data being overwritten is on the stack in a function which is
called after the problematic scanf() etc are are run.

I would suggest running up GDB and do a break on access of the overwritten
lvalue.  

Regards, 

Victor Webber
V&T: 408-221-8467 
V:      805-924-1953
vwebber@msn.com


-----Original Message-----
From: pinskia at gcc dot gnu.org <gcc-bugzilla@gcc.gnu.org> 
Sent: Saturday, April 23, 2022 1:07 AM
To: vwebber@msn.com
Subject: [Bug c/105357] dereferenced ptr on param stack gets over written

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Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- You need
better error checking in your code.
scanf can fail and scanf with %s without a size can definitely have a buffer
overflow.

You might be able to detect some of this with -fsanitize=address or by using
valgrind.

This is almost definitely not a bug in GCC.

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