svn commit: r267678 - head/libexec/rtld-elf

[Mateusz Guzik]

On Fri, Jun 20, 2014 at 05:08:32PM +0000, Jonathan Anderson wrote:
> Author: jonathan
> Date: Fri Jun 20 17:08:32 2014
> New Revision: 267678
> URL: http://svnweb.freebsd.org/changeset/base/267678
> 
> Log:
>   Add the LD_LIBRARY_PATH_FDS environmental variable.
>   
>   This variable allows the loading of shared libraries via directory descriptors
>   rather than via library paths.  If LD_LIBRARY_PATH_FDS=3:4:12, the directories
>   represented by file descriptors 3, 4 and 12 will searched for shared libraries
>   before the normal path-based mechanisms are used.  This allows us to execute
>   unprivileged binaries from within a Capsicum sandbox even if they require
>   shared libraries.
>   

This is not a request, but a mere suggestion.

Now there are 2 places where rtld opens requested libraries which is
somewhat unfortunate.

If find_library was changed to return directory fd to lookup the library
in and the path, open could be done in load_object with openat.

Old functions would return AT_FDCWD.

As a side note load_object would really use an assert that only one of
fd_u and name is set.

Cheers,
-- 
Mateusz Guzik <mjguzik gmail.com>