<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.
<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
<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
<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 Does this mean that the "small hack entry" on the contributing page to use libz and libbz2 in exec is no longer valid?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.