USB Issues [0/4]

[Binyamin Sharet]

Hi All,

I have used Umap2 to scan OpenBSD 5.9 on i386 for supported USB devices,
and during this scan I have found 4 issues with the USB stack.
Umap2 can be downloaded from github [1].

The scanning requires some hardware - facedancer/beaglebone board,
and consists of emulating USB devices with single configuration,
single interface and multiple (5 IN, 5 OUT) endpoints on this interface.
Each time the VID (vendor ID) and PID (product ID) of the emulated USB
device are changed to match one of 155 known USB VID/PID that are
currently in a DB in Umap2. It aims on triggering the specific driver
for that VID/PID combination in order to detect support for it in the OS.

I would refer to the issues by their VID/PID tuple from now.

The first two issues - 13d3_3346 and 0cf3_9170 (handling devices with
VID/PID 0x13d3/0x3346 and 0x0cf3/0x9170) cause a kernel panic due to
kernel diagnostic assertion in the usbtask (file dev/usb/ehci.c,
line 1654).

The third issue - 50c2_4013 - is a page fault, caused when trying to
read from invalid address in ehci_check_intr (movzbl 0x3(%eax), %eax).

The fourth issue - 04bb_0904 - does not cause a crash, but it seems to
cause the USB stack to hang, and so it does not communicate with any
device that is inserted after this one, even if it was removed.
I was not able to find any more information about this one.

All issues were reproduced on my machine multiple times.

In the next 4 emails I will send the details regarding each of the
issues, as this is my first encounter with OpenBSD, I am not very
familiar with debugging and analyzing the system, and I'll surely
miss some required information.
If so, please let me know what's missing and I will try my best to
provide it.
Most of the information is based on pictures, as I couldn't copy
the data from the computer in any other way. If there is - please
let me know.

Regards,
Binyamin Sharet
Cisco, STARE-C

[1]: https://github.com/nccgroup/umap2