Re: [GIT]: Networking

From: Jouni Malinen
Date: Mon Sep 08 2008 - 22:42:24 EST


Alex Williamson wrote:
On Wed, 2008-08-27 at 16:46 -0700, David Miller wrote:

22) Two mac80211 bug fixes from Jouni Malinen:
a) Use IWEVCUSTOM so that we don't hit the 256 byte limit that
IWEVASSOCREQIE has

By the way, that description is incorrect; the change was in the other direction (i.e., to use IWSSOCREQIE).

This one breaks wireless with 32bit userspace/64bit kernel. Bisected
back to changeset 087d833e5a9f67ba933cb32eaf5a2279c1a5b47c:

mac80211: Use IWEVASSOCREQIE instead of IWEVCUSTOM

Great.. I was hoping that the WEXT compat ioctl fixes from Dave resolved all WEXT cases. This code is (and was) using wireless_send_event() and I did not find clear changes to its use in Dave's patch set. Was that supposed to be fixed with the compat ioctl patches? I'm not very familiar with this area and don't have an easy way to test this now (I'm traveling and don't have access to a 64/32-bit setup).

As far as I can tell, the commit mentioned here is correct in itself, but it looks like the WEXT code would not handle something properly for wireless_send_event(). I'm not sure why IWEVCUSTOM would work any better, but well, maybe it does not have some fields that get wrong in 64/32 case or the previous working case ended up getting the too-long-buffer error which prevented the message from being processed in userspace).

What exactly does "breaks wireless" mean here?

As far as resolving this quickly is concerned, reverting the change is fine; this is not a critical issue with most use cases. Anyway, this should really be fixed eventually, but it looks like someone would need to fix WEXT for wireless_send_event() first..

- Jouni
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/