From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1628D3D891D for ; Tue, 7 Jul 2026 12:47:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783428446; cv=none; b=Xgy/f3Mg+CcUS7JmZJO4JJG+SXaBKDpIdlXp5J37wbzXH6fG5D8oyEpeymdLiu6zY2THbmPxBgA54lHE3q55To4e8fNRqA/A3Tb9RA1vNG5RxVwo64RBFsvgO9uyg+KONXcjt+V3w8P9tlepkY6JDxs9zEJAwpYVD/vQEV9+9qU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783428446; c=relaxed/simple; bh=hEE3m3WVJuBFnAm3gjDrsTE+bClUghMxtBjGH4/4pak=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=r9Y3UPifL+RYQIW419PH+zkn95StGyMw2ZDCm6GE/gfmM/uIuCBJCOWpBiEnAT5ONkvFsvGo6p2Xj6WI964DWYxPhcD4lbtW0A7GcyxQ9u5zP2nUqWzqcJYCPZDDo8KT9x5ySbnYXtUSsYzA7OdkvKiYWn9Za95UUE6or5sZbXg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dh2ykrRT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dh2ykrRT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F51F1F00A3D; Tue, 7 Jul 2026 12:47:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783428444; bh=hEE3m3WVJuBFnAm3gjDrsTE+bClUghMxtBjGH4/4pak=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=dh2ykrRTucW/VBrxB9M+J/VOLxuu8Lp95gVoTmE/Xe1V/jHHEAVNrNpBPWO+ZIBXt HG+X8VMiuLB4EZ9AKx7hjBsSp++azCCCIWW/C337n6ePgDj45+2IvH3Ms3ctzZQW8X kvD21TM/G5banmvITBwHlXzBgWdEgf/b1ajmy+3+asmEKFWAckNYgoCcpZDiOphpcd VC4WI0myBdBHSmnabwjUPsIaXePp2p6H2sRRuYtoNlLoX2MW8n0pjYjQBDi2OQDdYV ngTsYJmUH7nO8cyxfaaE2MM+N/yece/OeonxsgVKvveXcZwK+8IYV6OXIHuwG+j4Oy r4gBfxReXLBmQ== Date: Tue, 7 Jul 2026 13:47:14 +0100 From: Lorenzo Stoakes To: Russell King Cc: Qi Xi , Xie Yuanbin , akpm@linux-foundation.org, david@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, linusw@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, sunnanyong@huawei.com, linux-mm@kvack.org, lilinjie8@huawei.com, liaohua4@huawei.com Subject: Re: [PATCH v3 1/2] ARM: mm: fix use-after-free in __do_user_fault() under CONFIG_DEBUG_USER Message-ID: References: <20260626073048.3595106-2-xiqi2@huawei.com> <20260706133247.145485-1-xieyuanbin1@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jul 07, 2026 at 12:57:45PM +0100, Russell King wrote: > On Tue, Jul 07, 2026 at 07:48:12PM +0800, Qi Xi wrote: > > You're right. And I think the fix is to simply skip show_pte() for kernel > > addresses. > > No. This information is useful debug for kernel oops. Yup see my reply, just upgrade it to an mmap write lock and you should be safe to keep this. > > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! Cheers, Lorenzo