On Thu, Aug 18, 2022 at 12:30:21PM +0200, Laszlo Ersek wrote: > On 08/18/22 11:53, Richard W.M. Jones wrote: > > > > This is upstream in 5 commits 5764fa6f4..dd28b0054: > > > > https://gitlab.com/nbdkit/nbdkit/-/commit/2620d95a4585204f0db0d55c0d41276d11970436 > > https://gitlab.com/nbdkit/nbdkit/-/commit/185e7d4010b353f36b5ca5d47467a770c530e58c > > https://gitlab.com/nbdkit/nbdkit/-/commit/17655b1ca67caa454e7a4ac83bc8c052b79a692d > > https://gitlab.com/nbdkit/nbdkit/-/commit/e7fdffde8142fb083625678b7a55455751185502 > > https://gitlab.com/nbdkit/nbdkit/-/commit/dd28b005430d020ccd1825437937c317332d3007 > > > > This also includes dirfd functionality and a rather complicated test > > for that. Turns out that bash refuses to open a directory as a file > > descriptor :-( > > This doesn't match my experience; for me, bash opens e.g. /tmp just fine > on both RHEL7 and Fedora35 -- but it must be a read-only open. > > $ exec 9</tmp > [ok]
Hmmm, that makes sense since we don't even need to write to the directory. Let's see if I can simplify that test ... > $ exec 9<>/tmp > bash: /tmp: Is a directory > > The latter is actually expected; it comes from open(). See EISDIR at > <https://pubs.opengroup.org/onlinepubs/9699919799/functions/open.html>. > > Commit dd28b005430d also adds > > dfd = open (tmpdir, O_RDONLY | O_DIRECTORY); > > where I think O_DIRECTORY is not strictly necessary (per spec, because > O_CREAT is absent, O_DIRECTORY only helps us refuse a non-directory -- > but we do not expect such "attacks" here). So my take is that > O_DIRECTORY could be dropped from the C code, at which point a bash > redirection (read-only) should work just the same. > > Laszlo Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org _______________________________________________ Libguestfs mailing list [email protected] https://listman.redhat.com/mailman/listinfo/libguestfs
