2018-02-23 01:15:42

by [email protected]

[permalink] [raw]
Subject: Proposal - how to make usbip more resistant to misconfiguration

Hi,

I have found that the
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=891036 is not the only
one related to misconfiguration of the usbip driver and tools.
A few weeks ago the similar bug
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878866 was discovered.
It seems that the configuration of usbip is fragile, and it is easy to
make a mistake leading to the setup that doesn't work correctly.
I suppose, that additional mechanisms should be added to prevent such
problems:

1. It should be checked DURING THE COMPILATION, that the number of
ports in a single virtual hub does not exceed 128.
2. The MAXNPORT constant in tools/usb/usbip/libsrc/vhci_driver.h should
be defined as:
#define MAXNPORT ( VHCI_PORTS * VHCI_NR_HCS )

I have not tested the above modifications. If I find some time to verify
them, and if they are correct, I'll submit the official patches.

With best regards,
Wojtek

--
Wojciech M Zabolotny, PhD
Institute of Electronic Systems
Faculty of Electronics and Information Technology
Warsaw University of Technology