Re: GNU bash, 3.00.15(1)-release, referenced cmd in cwd executes alternate cmd

[Matthew Woehlke]

Bob Proulx wrote:
> Matthew Woehlke wrote:
> > Бојан Ландекић wrote:
> > > Is it possible to put bash on some portable media and use it on a
> > > system that is bash-less without worrying about dependencies?
> > Not unless you build it statically, it isn't. :-) Although I think if 
> > you build bash it gives you all the libraries you need except for libc 
> > (or your OS's equivalent). IOW if you have an entire bash install on 
> > your 'portable media', you should be able to run that bash on any system 
> > the same as, or newer than, your build system.
>
> Actually as long as you include all of the libraries in the same
> bundle and call ldso with the path to the bundled libc then it is
> perfectly possible to build a complete set that will work on most
> distros, on the same architecture and across compatible kernel
> versions of course.  On my system that would be libncurses.so.5,
> libdl.so.2, libc.so.6, ld-linux-x86-64.so.2 plus bash itself and a
> portable sh script wrapper to tie it all together.  I do that with
> other tools frequently.

Oddly enough, I can get this to work on OSF, but not Linux. I don't want 
to use a bundled libc unless the system libc is sufficient, so what I 
did was drop a "sufficient" libc somewhere I can LD_LIBRARY_PATH it 
before trying to run bash. Like I said, this works on OSF, but on Linux 
I get:

$ ldd /path/to/bash
/path/to/bash: /lib/i686/libc.so.6: version `GLIBC_2.3' not found 
(required by /path/to/bash)
        libtermcap.so.2 => /lib/libtermcap.so.2 (0x40021000)
        libdl.so.2 => /lib/libdl.so.2 (0x40025000)
        libc.so.6 => /lib/i686/libc.so.6 (0x40029000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)

...At some point I was also getting:

$ ldd /path/to/bash
/bin/sh: /lib/ld-linux.so.2: version `GLIBC_PRIVATE' not found (required 
by /path/to/my/private/libc.so.6

...but I can't seem to reproduce this any more (I think it happened if I 
dropped in libdl also).

Apparently selectively shadowing libc is non-trivial... any 
suggestions/hints?

--
Matthew
Obscurity: +5