Re: nonstrings in Glibc

[Florian Weimer <fweimer at redhat dot com>]

On 11/20/2017 07:20 PM, Carlos O'Donell wrote:
> On 11/20/2017 08:54 AM, Martin Sebor wrote:
> > I'm done testing my update to the -Wstringop-truncation GCC patch
> > to find misuses of non-string arrays.  With the very limited use
> > of attribute nonstring it only found one potential bug (22447).
> > I've been looking at other uses of strncpy in Glibc to see if there
> > are other arrays that would benefit from the attribute.  I'm not
> > sufficiently familiar with Glibc data structures so it's a very
> > slow going.  Could someone help suggests data structures with
> > array members that might be candidates?
>
> struct sockaddr's sun_path?
>  > http://thread.gmane.org/gmane.comp.standards.posix.austin.general/5735

Please include some context in case the link target goes away.

This discussion was about the flexible array member nature of sun_path. 
Another complication is the overloading of the member with the abstract 
namespace (leading NUL byte).

For the variable length member, d_name in struct dirent is another 
example.  For struct dirent and struct dirent_64, all uses which rely on 
a fixed size of the d_name member should probably result in warnings.

Thanks,
Florian