From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C908C56202 for ; Wed, 25 Nov 2020 11:48:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D2FF206D9 for ; Wed, 25 Nov 2020 11:48:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kroah.com header.i=@kroah.com header.b="lPhdItbF"; dkim=temperror (0-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="jta7XShb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727982AbgKYLsn (ORCPT ); Wed, 25 Nov 2020 06:48:43 -0500 Received: from wout2-smtp.messagingengine.com ([64.147.123.25]:47201 "EHLO wout2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725838AbgKYLsn (ORCPT ); Wed, 25 Nov 2020 06:48:43 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.west.internal (Postfix) with ESMTP id 9775EC8F; Wed, 25 Nov 2020 06:48:42 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Wed, 25 Nov 2020 06:48:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm2; bh=eDDmbS7x/P+kfvFMPpO+nwfcN+O q7iMUJdzmcknX/RY=; b=lPhdItbFMltSgeQ7VsdzUCA4hhjOIZlos8ZmYJJgor0 7Ts/oqQarHGginK5r00GwMuvb9E86lhHzg7upqP/fxWNCi4m6TOgDxJvOAuFD2rt YUTKmdUAvehdvlLmX6qg9/FnG8dNxbSA2bO6zvf1iBpjmUu0ubps+eCzJ9eHxm6y B9RvZN/Jis1ypcZ3pKNufyHHqN4Li9jh9Q55xeZ6jkvPLSuvG1VTemp3rbLqFtqu WJ+arp2CfmeABU/3oTC6F2R0ZZayEkxyItA2WwLFCory8eYchxt38Pp8/e3x6i8y KDKQoFcWf96XV2vTXBkgyZ2prmvf6Z2jHhlv4Wm7OYA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=eDDmbS 7x/P+kfvFMPpO+nwfcN+Oq7iMUJdzmcknX/RY=; b=jta7XShbC5k613LaKcVD7i CEsZnYhRh/jZc8PiZwwO6vwoHyfiYpbx0NpN4SwNZY32qR12MT3tsIGfR7S5p+Y8 wnKlLUk3blPSurGnK+DwUWto3S43TGtZwT0r0vmycrBXJLTROWc94Q5mjyc3ODrp 6GRE4mcjq9VC85WStLSYXoNuu7Ec9A+Z8nNxL73pDr2GoQa6ox3D8XwMe0/RwLRn GCC2+TMTLC0a5UEHpq8nXTiSBFQpkXhoQjtmm4SXC6dfjMtEqwICBHaMh7IlDQnS +tEsoRzi9zNSqmV/pMCDU1gmYqOAuZuA4JOxN/RYmbghj5LAhcU2MTMG9O1xt63w == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedrudehtddgfeefucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvffukfhfgggtuggjsehttdertddttddvnecuhfhrohhmpefirhgvghcu mffjuceoghhrvghgsehkrhhorghhrdgtohhmqeenucggtffrrghtthgvrhhnpeevueehje fgfffgiedvudekvdektdelleelgefhleejieeugeegveeuuddukedvteenucfkphepkedv rddvudejrddvtddrudekheenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmh grihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (82-217-20-185.cable.dynamic.v4.ziggo.nl [82.217.20.185]) by mail.messagingengine.com (Postfix) with ESMTPA id 93A8A3064AA6; Wed, 25 Nov 2020 06:48:41 -0500 (EST) Date: Wed, 25 Nov 2020 12:48:39 +0100 From: Greg KH To: Alexander Dahl Cc: stable@vger.kernel.org Subject: Re: perf: Apply e9a6882f267a to v4.9 stable (fix for null-pointer dereference) Message-ID: References: <4431770.U1WXKbcAmY@ada> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4431770.U1WXKbcAmY@ada> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Nov 25, 2020 at 11:01:39AM +0100, Alexander Dahl wrote: > Hei hei, > > please apply e9a6882f267a8105461066e3ea6b4b6b9be1b807 ("perf event: Check > ref_reloc_sym before using it") to the v4.9 stable tree and maybe to later LTS > trees (v4.14, v4.19) as well. > > That change is in mainline since v5.4-rc1 and it's a fix for a possible null > pointer dereference in the tool 'perf', so it is a fix for a user space tool > coming with the kernel tree actually. > > I am directly affeted by this, calling 'perf record' on an at91 based device > (armv5te, sam9g20 soc) running PREEMPT RT kernel 4.9.220-rt143 results in a > segfault here. I debugged this with gdb and tracked it down to the exact > pointer being NULL, which is checked now in that above mentioned changeset. > > I could cleanly apply that changeset to my local tree and the segfault is not > triggered anymore, I can use perf on that platform now. > > I only tested this on the above mentioned v4.9 based kernel version. Now queued up, thanks. greg k-h