> I think I've figured out what's happening here. > > The kernel makes no effort whatsoever to translate iwe streams in > compat environments. And userspace then tries to "correct" this and > does so miserably. Likely this is what causes the bus error. Quite possible. I wanted this fixed too but Jean refused to do it in the kernel. And personally, I'm no longer touching wext with a 10 foot pole. Too much backslash. > The fix is that we need to add some handling code > fs/compat_ioctl.c:do_wireless_ioctl() for the case where we are > returning an iwe stream (SIOCGIWSCAN). > > It should not be very difficult to do this, since the compat format > will be the same size or smaller, it should be easy to recode the > thing in-place in the user buffer. > > So you make a pass over the user buffer fixing things up and then you > adjust the iw_data length for the new size. > > Alternatively, you can allocate a kernel buffer for this, use a 'fs = > get_fs(); set_fs(KERNEL_DS); ioctl(); set_fs(fs);' sequence, fixup the > iwe stream, then copy the everything back out to userspace. That may work, but wext also broadcasts iw_point inside netlink messages for scan notifications etc. I don't see a good way to fix this part. > Then we can delete all of this incredibly stupid code in the wireless > tools that attempts to fix this up in userspace. I wish. Really, I do. johannes
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