On Thu, Jan 30, 2025 at 10:13:14PM +0100, Johannes Berg wrote: > On Thu, 2025-01-30 at 22:23 +0300, Fedor Pchelkin wrote: > > Wouldn't it break existing userspace, especially in context of systems > > running old stable kernels where the patch is also needed? > > > > There is still some usage of this flag in hostap [1]. > > Theoretically, but I just commented on that here: > > https://lore.kernel.org/r/a49e58998553c45953a30243ad1957c06ce6db8c.camel@xxxxxxxxxxxxxxxx > > tl;dr: only ancient hostapd versions will actually _use_ it, and they > have to fall into a relatively narrow range (April 2009 - Dec 2011.) How did you determine that commit a11241fa1149 ("nl80211: Use nl80211 for mgmt TX/RX in AP mode") ends this use? Support for monitor mode interface is still in hostap.git and it is even tested as part of the hwsim test cases.. Both hostapd and wpa_supplicant can still be configured to use the monitor interface. It would be another question to ask whether there is any good reason to use this anymore now that a better approach has been available for 13 years and the answer to that is likely "no". Anyway, this is a kernel interface that has a user even in the current snapshot of user space programs. If we are about to break that use, it would make sense to first remove such users. I don't think I would really care about this anymore and it would be nice to get rid of all that unlikely to be used much, if at all, code. > > Or your suggestion is to explicitly reject setting MONITOR_FLAG_COOK_FRAMES > > only when it is passed combined with some other flags which it is > > incompatible with? > > Yes. Though, this seems to imply that the case used by hostapd/wpa_supplicant would not be broken. -- Jouni Malinen PGP id EFC895FA
