Comment 16 for bug 1729337

@FedeX

It's interesting that reverting to 3.13.0-133 fixed the issue since there are no cifs related change from 3.13.0-133 to 3.13.0-135.

Also, according to upstream kernel bugzilla 197311, it's mentioned that this was introduced by:
0603c96f upstream ("SMB: Validate negotiate (to protect against downgrade) even if signing off")

However, this commit was not backported to Trusty. Would it be possible for you to assist with a kernel bisect to identify the specific commit that introduced this bug in trusty? It would require you testing 3 - 5 test kernels.

I started a kernel bisect between Ubuntu-3.13.0-133 and Ubuntu-3.13.0-135.

I built the first test kernel, up to the following commit:
5165d87e2242f7d253eca47f4a15ff2cf62eac53

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1729337

If you can assist with a bisect, would it be possible for you to test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Note, just be sure to install both the linux-image and linux-image-extra .deb packages for these kernels.

Thanks in advance