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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 203A6C433F5 for ; Fri, 27 May 2022 13:27:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352185AbiE0N1h (ORCPT ); Fri, 27 May 2022 09:27:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235460AbiE0N1d (ORCPT ); Fri, 27 May 2022 09:27:33 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B53B83057F for ; Fri, 27 May 2022 06:27:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=dJg7G2nPL/gjA12rwYq4JM6XgoNicJnOgK9xyJkk0Gg=; t=1653658052; x=1654867652; b=U9APU1LJPWUieD2+cduNaRIVhwBPzgdMXfn0k3iNE+WTi2M PiizYdN96UrAo0dE4GhM4oEjXOEkAe8QIiyVsGvaIfZiOZU4ncLWqlB8vRoEJVYQNP5o2fABr1DL/ IAZyEAmLhBOmoQV0Kbnx/udnWaHZ9mGw+dcVXQNnhFN9XSx5IPingLIElp/TdOa3ql5SISsuJkWXw 8j1f9lKIpDOMzf2INWrj3xk+2MUi6oLW8FVYsHeQqIDaEc5Fpeg5V4WRb11kURRxxOqwTSyxgJrHZ Pade4j3CGqEEdGr5JZlOmyDJmQ1YdN7qk0KX7TyCWbnN7eriMCea4mabE5vhA6Ig==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.95) (envelope-from ) id 1nuZzw-0063Un-KX; Fri, 27 May 2022 15:27:24 +0200 Message-ID: <134957369d2e0abf51f03817f1e4de7cbf21f76e.camel@sipsolutions.net> Subject: Re: [RFC PATCH v3] UML: add support for KASAN under x86_64 From: Johannes Berg To: Dmitry Vyukov Cc: David Gow , Vincent Whitchurch , Patricia Alfonso , Jeff Dike , Richard Weinberger , anton.ivanov@cambridgegreys.com, Brendan Higgins , kasan-dev , linux-um@lists.infradead.org, LKML , Daniel Latypov Date: Fri, 27 May 2022 15:27:23 +0200 In-Reply-To: References: <20220525111756.GA15955@axis.com> <20220526010111.755166-1-davidgow@google.com> <6fa1ebe49b8d574fb1c82aefeeb54439d9c98750.camel@sipsolutions.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.1 (3.44.1-1.fc36) MIME-Version: 1.0 X-malware-bazaar: not-scanned Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2022-05-27 at 15:18 +0200, Dmitry Vyukov wrote: > On Fri, 27 May 2022 at 15:15, Johannes Berg w= rote: > >=20 > > On Fri, 2022-05-27 at 15:09 +0200, Dmitry Vyukov wrote: > > > > I did note (this is more for kasan-dev@) that the "freed by" is fai= rly > > > > much useless when using kfree_rcu(), it might be worthwhile to anno= tate > > > > that somehow, so the stack trace is recorded by kfree_rcu() already= , > > > > rather than just showing the RCU callback used for that. > > >=20 > > > KASAN is doing it for several years now, see e.g.: > > > https://groups.google.com/g/syzkaller-bugs/c/eTW9zom4O2o/m/_v7cOo2RFw= AJ > > >=20 > >=20 > > Hm. It didn't for me: >=20 > Please post a full report with line numbers and kernel version. That was basically it, apart from a few lines snipped from the stack traces. Kernel version was admittedly a little older - 5.18.0-rc1 + a few UML fixes + this KASAN patch (+ the fixes I pointed out earlier) I guess it doesn't really matter that much, just had to dig a bit to understand why it was freed. johannes From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from s3.sipsolutions.net ([2a01:4f8:191:4433::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nua01-0007rw-3l for linux-um@lists.infradead.org; Fri, 27 May 2022 13:27:31 +0000 Message-ID: <134957369d2e0abf51f03817f1e4de7cbf21f76e.camel@sipsolutions.net> Subject: Re: [RFC PATCH v3] UML: add support for KASAN under x86_64 From: Johannes Berg Date: Fri, 27 May 2022 15:27:23 +0200 In-Reply-To: References: <20220525111756.GA15955@axis.com> <20220526010111.755166-1-davidgow@google.com> <6fa1ebe49b8d574fb1c82aefeeb54439d9c98750.camel@sipsolutions.net> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Dmitry Vyukov Cc: David Gow , Vincent Whitchurch , Patricia Alfonso , Jeff Dike , Richard Weinberger , anton.ivanov@cambridgegreys.com, Brendan Higgins , kasan-dev , linux-um@lists.infradead.org, LKML , Daniel Latypov On Fri, 2022-05-27 at 15:18 +0200, Dmitry Vyukov wrote: > On Fri, 27 May 2022 at 15:15, Johannes Berg wrote: > > > > On Fri, 2022-05-27 at 15:09 +0200, Dmitry Vyukov wrote: > > > > I did note (this is more for kasan-dev@) that the "freed by" is fairly > > > > much useless when using kfree_rcu(), it might be worthwhile to annotate > > > > that somehow, so the stack trace is recorded by kfree_rcu() already, > > > > rather than just showing the RCU callback used for that. > > > > > > KASAN is doing it for several years now, see e.g.: > > > https://groups.google.com/g/syzkaller-bugs/c/eTW9zom4O2o/m/_v7cOo2RFwAJ > > > > > > > Hm. It didn't for me: > > Please post a full report with line numbers and kernel version. That was basically it, apart from a few lines snipped from the stack traces. Kernel version was admittedly a little older - 5.18.0-rc1 + a few UML fixes + this KASAN patch (+ the fixes I pointed out earlier) I guess it doesn't really matter that much, just had to dig a bit to understand why it was freed. johannes _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um