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"Unidata User Support": Re: Error in netcdf 2.3.2

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  • Subject: "Unidata User Support": Re: Error in netcdf 2.3.2
  • Date: Tue, 05 Jul 1994 14:35:21 -0600
  • >keywords: 199406241439.AA19966 netCDF header file
  • >organization: Research Systems
Hi Beth,

>I don't know if you have run across this error or not, but
>in local_nc.h the memory for the path field is not being allocated
>correctly.   The path field is currently set to be FILENAME_MAX
>which varies on different systems (sometimes less than 255) and MAXPATHLEN
>is 255.   
>
>The strncpy routine in file.c pads to MAXPATHLEN on non-null terminated 
>strings.  Because the path field wasn't allocated correctly, memory was 
>getting clobbered and causing the software to seg fault.
>
>Our fix was to change the path field to be MAXPATHLEN and set MAXPATHLEN
>to more realistic values for the systems we were using.   I included
>the fix below.

Thanks for reporting this.  We apparently had discovered this bug previously
and fixed it by eliminating the use of MAXPATHLEN in favor of FILENAME_MAX
everywhere in the netCDF source code.

I'm surprised you saw this bug, since the use of MAXPATHLEN was apparently
eliminated from the netCDF 2.3 distribution over a year ago.  Perhaps you
are looking at an older version of the source?  The version of local_nc.h
that is in the current netCDF 2.3.2 version is from April 27 1993:

/* $Id: local_nc.h,v 1.39 1993/04/27 20:05:21 davis Exp $ */

--
Russ Rew                                                   UCAR Unidata Program
address@hidden                                             P.O. Box 3000
http://www.unidata.ucar.edu/                             Boulder, CO 80307-3000