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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page to use libz and libbz2 in exec is no longer valid?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.
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