Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:52314 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753035AbeEUQZo (ORCPT ); Mon, 21 May 2018 12:25:44 -0400 From: Kalle Valo To: Luca Coelho Cc: Eric Biggers , Intel Linux Wireless , linux-wireless@vger.kernel.org, Haim Dreyfuss Subject: Re: [4.17 iwlwifi regression] NULL pointer dereference in reg_query_regdb_wmm() References: <20180519183345.GA701@sol.localdomain> <1469fa7134c62e0323ea1b409d98953f6c1a70a3.camel@coelho.fi> Date: Mon, 21 May 2018 19:25:38 +0300 In-Reply-To: <1469fa7134c62e0323ea1b409d98953f6c1a70a3.camel@coelho.fi> (Luca Coelho's message of "Mon, 21 May 2018 10:42:00 +0300") Message-ID: <87r2m5f01p.fsf@kamboji.qca.qualcomm.com> (sfid-20180521_182547_805589_47624275) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Luca Coelho 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? -- Kalle Valo