Luca Coelho <[email protected]> writes: > On Mon, 2018-05-21 at 19:25 +0300, Kalle Valo wrote: >> Luca Coelho <[email protected]> writes: >> >> > On Sat, 2018-05-19 at 11:33 -0700, Eric Biggers wrote: >> > > Hello, >> > > >> > > Using v4.17-rc5, on a laptop with an "Intel Corporation Wireless >> > > 3165 >> > > (rev 79)" >> > > using the iwlwifi driver, I get a NULL pointer dereference >> > > immediately after >> > > boot. Apparently, the 'regdb' variable in net/wireless/reg.c is >> > > NULL, yet >> > > reg_query_regdb_wmm() is checking for IS_ERR(). It goes away if >> > > I >> > > revert commit >> > > 77e30e10ee28a5 ("iwlwifi: mvm: query regdb for wmm rule if >> > > needed"). The >> > > symbolized crash report is: >> > > >> > > BUG: unable to handle kernel NULL pointer dereference at >> > > 000000000000000a >> > >> > Thanks for the report and analysis! Haim is working on a fix and I >> > will >> > send it out later today. >> >> We are on -rc6 already and getting close to the final v4.17 release. >> I >> wonder should we just revert 77e30e10ee28a5 for now? > > I don't think we should revert it, this implements the new ETSI > requirements for the WMM settings and this will be enforced in all new > devices sold after mid-June (IIRC). > > We haven't seen this problem and cfg80211 should not crash if the > driver does stupid things, so we should just reject the call if regdb > is still NULL. It's a simple fix for the crash and the driver should > recover from the issue later on. > > I'll push the patch for cfg80211 later this evening.
Very good that we have a quick fix, and I assume that will go through mac80211 tree so I can send my w-d pull request tomorrow. -- Kalle Valo
