From patchwork Mon Sep 20 16:43:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 514354 Delivered-To: patch@linaro.org Received: by 2002:a02:c816:0:0:0:0:0 with SMTP id p22csp2315804jao; Mon, 20 Sep 2021 11:20:25 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyJ51xPJxzM8Sm1pcSgBP3p4LSu1gDOnZyMdSGFucUZs/aqWzsDrK2g7LRTLlP5SNZ7UNVE X-Received: by 2002:a17:906:7fc4:: with SMTP id r4mr31211812ejs.75.1632162021958; Mon, 20 Sep 2021 11:20:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1632162021; cv=none; d=google.com; s=arc-20160816; b=ZL7BB/zKQfvlDmhjPPnmfK8lTqZug9Tv7l6+Qfte2bv4PM0gaTdV4HNjHuy6iVZhLa gT0MMuw36fczWqDcgOO3UiU9x8Oe8vd8c44lQDiX4ilP2pdqCdfgcrTZ64gyb+25k4LQ 4FNC84eYsn6COgS/a0mRMnsp3mBePUrgfMUGc8zghRFvmqG9gOpw0uZ+31oaKFVyUtpQ AMXSZuh3e2B46jMHoNiMrhozbi6oIO8kFkU/nj39vxnv/kqxRs27nENNgyQtGBnSuVAE YHCES/b57Nhytp9EMUH+vWiB4jXQaY6xv3ALgsm7LTFOrehX2XDLjRCjnS52Etn1fhm9 SQ8Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=dXnfEh7ZsgGPGNE3s4YRkCxMgFfs8Mcxcg3okfpUptc=; b=gbHv62vADIioXuh+2P5dEcxlvXsdJ0hpUMge2/N+Pisy/vhMqbK0YPfNWaT312oegi QiDcugbKW1JtsOq6GGQZ9VANpz7TjK6dLKsn2DRVtmOjMQqnYCMipVHwsC39VQzoasrI ivbiw/PXfY+N33u+qH7nSLD4hCLZjYT0DDxooqNKFY26BM/pUnqMnEtIxVLdLt6hXPL1 4VyACF2fqijTt9Y/rnMTKRYIbQKQY4akh4F+ET8/2VZSFXenmzKpVxQ9I10p75NTThK0 t1HmlwvoeBESEoWxWhga4vv5S7D9kQ9JfgnB+cYrseMtYUPgfQGxyEtDMJIlh+p19XiW irZw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=RklfHSS0; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id n7si16605055ejl.237.2021.09.20.11.20.21; Mon, 20 Sep 2021 11:20:21 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=RklfHSS0; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377793AbhITSU6 (ORCPT + 11 others); Mon, 20 Sep 2021 14:20:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:40990 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344009AbhITSS5 (ORCPT ); Mon, 20 Sep 2021 14:18:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A6DF9632AB; Mon, 20 Sep 2021 17:23:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632158593; bh=nFgCtX4TUZ4Is7S8X4Jxx5TU8pPnTOTTKO3PHLhqnzU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RklfHSS0yBz1QEEi3ZNwrA9Lh9/qWxkf0TOOJjLMee1nR5ai/yxYzNpIwC2/sZw5t u7Z1bozKHIv9YIgoIqKS+rXhVRrpMUUzGzfyAk8hTWFEyP7vRG50ko/xSCGhaPLTL+ kbE+nQVZnXb8fkcC6p4aBiFRnOi3hCGfjHz1i3yo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mark Brown , Catalin Marinas Subject: [PATCH 5.4 195/260] arm64/sve: Use correct size when reinitialising SVE state Date: Mon, 20 Sep 2021 18:43:33 +0200 Message-Id: <20210920163937.737954530@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210920163931.123590023@linuxfoundation.org> References: <20210920163931.123590023@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mark Brown commit e35ac9d0b56e9efefaeeb84b635ea26c2839ea86 upstream. When we need a buffer for SVE register state we call sve_alloc() to make sure that one is there. In order to avoid repeated allocations and frees we keep the buffer around unless we change vector length and just memset() it to ensure a clean register state. The function that deals with this takes the task to operate on as an argument, however in the case where we do a memset() we initialise using the SVE state size for the current task rather than the task passed as an argument. This is only an issue in the case where we are setting the register state for a task via ptrace and the task being configured has a different vector length to the task tracing it. In the case where the buffer is larger in the traced process we will leak old state from the traced process to itself, in the case where the buffer is smaller in the traced process we will overflow the buffer and corrupt memory. Fixes: bc0ee4760364 ("arm64/sve: Core task context handling") Cc: # 4.15.x Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20210909165356.10675-1-broonie@kernel.org Signed-off-by: Catalin Marinas Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/fpsimd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -498,7 +498,7 @@ size_t sve_state_size(struct task_struct void sve_alloc(struct task_struct *task) { if (task->thread.sve_state) { - memset(task->thread.sve_state, 0, sve_state_size(current)); + memset(task->thread.sve_state, 0, sve_state_size(task)); return; }