Title: Message
All,
I have been working
on a component that is included with samba called SMBSH. The binary allows
you to automount your NT shares by accessing your profile . I have
been working on this for the last few days and have been unsuccesful
at getting it work. Now I am not much of a programmer, but I did my best
to try and troubleshoot this. However it just does not want to work
in Linux. I notice that during an strace I can see that it is attempting
to create a shared environment by using FCNTL calls using 64bit locking.
Later in the code it tries to lock the environment again but I notice this
time the fcntl function stops using the 64bit function and ends
up using the 32bit argument. Which eventually forces the program to exit
because of an invalid argument
Portion of the
strace where it locks the shared environment and than unlocks it using fcntl64()
using 64bit arguments against it.
fcntl64(8191,
F_SETLKW64, {type=F_WRLCK, whence=SEEK_SET, start=0, len=1}, 0xbffff200) =
0
fstat64(8191, {st_mode=S_IFREG|0600, st_size=0, ...}) = 0
fcntl64(8191,
F_SETLK64, {type=F_UNLCK, whence=SEEK_SET, start=0, len=1}, 0xbffff200) =
0
Portion of the
strace where it sets the locks the shared environment again using fcntl() using
a 64bit argument against the function. Which is why I am getting an
invalid argument because that argument can not be used with that
function.
fcntl(8191,
F_SETLKW64, {type=F_WRLCK, whence=SEEK_SET, start=0, len=1}, 0xbfffeec0) = -1
EINVAL (Invalid argument)
write(2, "ERROR: can\'t get smbw shared loc"...,
53ERROR: can't get smbw shared lock (Invalid argument))= 53
What I am trying to
figure out is.. why is going from using fcntl64() to fcntl().. I have looked
through most of the source code and have found nothing. I have sent emails
to the samba lists and to redhat. So far I have gotten the following
responses.
Quote from
Redhat:
Hi, I have an update on your
issue!
A direct quote from engineering on your
issue:
" As I understand it, smbsh can not work on the
recent glibc versions as they no longer support the LD_PRELOAD features (hacks?
:) smbsh employs. On non linux unix variants smbsh will still work in general
(they dont after all use glibc). The LD_PRELOAD user space fs simply wont work
on recent glibc versions alas, LD_PRELOAD itself certainly still
works.
" It\'s the \"back door\" symbols _open, _read,
_write which allows smbsh to wrap around the normal file calls, possibly
redirect them to smb, and then call the actual C library function using the
underscore functions.
The GNU C library maintainers have decided to
remove support for these symbols in glibc 2.1and forward.
" So, overall maybe this is the good reason of
why we do not have smbwrapper/smbsh shipped :-)
" I would use autofs, to do the same
functionality. You\'d need a program that uses libsmb (or just calls smbclient)
to retrieve the browse list, and reformats it into an autofs
map."
Jp Robinson
I am just trying to
gather some thoughts here to see if anybody has has experiene with an issue like
this.. this may not be a samba thing but a GLIBC issue.. any ides? suggestions
on what to work on next?
Thanks,
Christopher Johnston
Merrill Lynch / DCSA
