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[[!tag open_issue_hurd]]

[[!toc]]


# IRC, unknown channel, unknown date.

    <youpi> oh my, disabling gzip/bzip2 support makes apt preconfigure hang
    <youpi> support in exec* I meant

    <youpi> now a funny bug: if I disable gzip/bzip2 support from exec
    <youpi> trying to run a zero-byte file hangs

Justus: This doesn't seem to be an issue anymore (2013-09-08):

    % touch empty
    % chmod +x empty
    % ./empty
    zsh: exec format error: ./empty
    % bash
    $ ./empty
    $ 

Also I've never encountered a problem with apt.


## IRC, freenode, #hurd, 2013-08-01

    <teythoon> uh, all the non trivial exec server code has #ifdef'd BFD code
      all over it and it looks like that isn't even used anymore
    <teythoon> that's too bad actually, I figured out how to get the values
      from BFD, not so for the other elf parser that is used instead


## IRC, freenode, #hurd, 2013-08-05

    <teythoon> btw, there is a Debian bug concerning zipped executables. now
      I'm not sure if I understood the problem, but gziped and bzip2ed
      executables work for me
    <teythoon> (not that I'm a big fan of that particular feature)
    <youpi> iirc these somehow got fixed yes
    <youpi> something like a previous out of bound access
    <teythoon> the exec server contains lot's of code that is unused and
      probably bit rot (#ifdef BFD) or otherwise ignored (#if 0)
    <youpi> yes :/
    <teythoon> and there's gunzipping and bunzip2ing, which we probably don't
      want anyway
    <pinotree> why not?
    <teythoon> we should strip all that from exec and start adding features
    <teythoon> pinotree: b/c it's slow and the gain is questionable
    <teythoon> it breaks mmapping the code in
    <teythoon> exec/exec.c is huge (~2300 lines) and complex and it is an
      essential server
    <teythoon> and I wonder if the unzipping is done securely, e. g. if it's
      not possible to crash exec with an maliciously compressed executable


## IRC, freenode, #hurd, 2013-09-12

    <rekado> The zip code in hurd/exec/ looks really complicated; does it
      really just unpack zipped files in memory (which could be replaced by
      library calls) or is there something else going on?
    <braunr> rekado:
      http://lists.gnu.org/archive/html/bug-hurd/2013-08/msg00049.html
    <rekado> braunr: interesting. Thanks.
    <rekado> Does this mean that the "small hack entry" on the contributing
      page to use libz and libbz2 in exec is no longer valid?
    <braunr> probably

---

May want to have a look at using BFD / libiberty/simpleobject.

Justus: The BFD code has been removed from the exec server.