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Date: Tue, 22 May 2007 10:16:52 +0300
From: "Lauri Leukkunen" <lle@rahina.org>
Sender: lauri.leukkunen@gmail.com
Subject: Re: [Qemu-devel] [PATCH][UPDATED] Fix path mangling in
	linux-user/path.c
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To: qemu-devel@nongnu.org

On 5/22/07, Kirill A. Shutemov <k.shutemov@velesys.com> wrote:
> On [Tue, 22.05.2007 02:22], Lauri Leukkunen wrote:
> > Attached patch fixes the linux-user path mangling code for use with
> > real target root filesystems that have nasty symlinks and lots of
> > files. The old code is terribly slow and can easily end up going
> > through the entire host system /usr hierarchy in a recursive loop.
> >
> > Compared to the previous version of this patch, fixes an issue with
> > attempting to free() a pointer returned by GNU basename().
>
> My patch to solve same problems attached

The added complexity of my version comes from preventing leaking out
of the "chroot" through symlinks or "../.." elements. If we have

$HOME/buildroot/usr/lib/libfoo.so.1 -> /usr/lib/libfoo.so.1.2 ->
/usr/lib/libfoo.so.1.2.3

and if the buildroot and host system have different versions of the
library, realpath can't be used. It gets a little messy, I agree. I
had to do similar logic in scratchbox2 to maintain the fake chroot.

regards, Lauri