[SOLVED] mount.cifs failing to mount after update to 3.8.x

Question

When trying to mount a CIFS share in Arch with kernel 3.8.3-2-ARCH, I get this:
mount error(22): Invalid argument
dmesg shows this:
FS-Cache: Loaded
FS-Cache: Netfs 'cifs' registered for caching
Key type cifs.spnego registered
Key type cifs.idmap registered
For clarity, I'm running this command (and have tried many others):
sudo mount.cifs //desktop/mydata /mnt/mydata -o user=me
Also, I am able to browse this share properly with smbclient, and I'm also able to mount it in distributions using older kernels.
I tested this on Ubuntu 13.04 as well, and the same problem happens there (also has kernel 3.8.x, so it seems likely that this is a kernel issue). From what I understand, portions of the mount.cifs client code were moved into the kernel recently, and the argument parser was overhauled at the same time (I found similar bug reports for Fedora, Gentoo, etc). Any ideas?
SOLVED:
The fix is to add "sec=ntlm" to the -o flag:
sudo mount.cifs //desktop/mydata /mnt/mydata -o user=me,sec=ntlm
Last edited by willroberts (2013-03-22 03:32:46)

Answer 1

While the "Permission denied" error seems completely different from an "Invalid argument" error, adding sec=ntlm to my -o flag fixed my issue as well.
For the record, I did search for my error message via Google, and got this:
https://www.google.com/search?q=site%3A … today&tbm=
No results for my "invalid argument" problem, but maybe that thread hasn't been indexed by Google yet. I'll try the built-in search next time. Most sites have notoriously awful built-in search, so I didn't even try.