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=-6.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 D47D8C43441 for ; Mon, 12 Nov 2018 00:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9646D2084C for ; Mon, 12 Nov 2018 00:19:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="XTgrJw6p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9646D2084C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730171AbeKLKKB (ORCPT ); Mon, 12 Nov 2018 05:10:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:58670 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726816AbeKLIQz (ORCPT ); Mon, 12 Nov 2018 03:16:55 -0500 Received: from localhost (unknown [206.108.79.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DA63A214F1; Sun, 11 Nov 2018 22:26:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541975219; bh=4RvXGiniDsyIXDx3U2bRoPLeQEzcTUuXUnIg+NybqrM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XTgrJw6pvof3iKBQuMuy2/pgjtd8gPNvKI+yXX6L4u7zBx3lmXH3O+KOp9NOxMIWT JOFz6l2/hJY6ufREegdT5bCpPynYxgf7LR+td3TW27IXfGqyrMp6Xx/wpN5vjL1Awr Q+4rXSxQqCKahUFnjhwf8KSoNhHBwVPDn8BB0gbg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, He Zhe , Marek Szyprowski , Christoph Hellwig Subject: [PATCH 4.19 022/361] dma-mapping: fix panic caused by passing empty cma command line argument Date: Sun, 11 Nov 2018 14:16:09 -0800 Message-Id: <20181111221622.775105965@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181111221619.915519183@linuxfoundation.org> References: <20181111221619.915519183@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: He Zhe commit a3ceed87b07769fb80ce9dc6b604e515dba14c4b upstream. early_cma does not check input argument before passing it to simple_strtoull. The argument would be a NULL pointer if "cma", without its value, is set in command line and thus causes the following panic. PANIC: early exception 0xe3 IP 10:ffffffffa3e9db8d error 0 cr2 0x0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc3-yocto-standard+ #7 [ 0.000000] RIP: 0010:_parse_integer_fixup_radix+0xd/0x70 ... [ 0.000000] Call Trace: [ 0.000000] simple_strtoull+0x29/0x70 [ 0.000000] memparse+0x26/0x90 [ 0.000000] early_cma+0x17/0x6a [ 0.000000] do_early_param+0x57/0x8e [ 0.000000] parse_args+0x208/0x320 [ 0.000000] ? rdinit_setup+0x30/0x30 [ 0.000000] parse_early_options+0x29/0x2d [ 0.000000] ? rdinit_setup+0x30/0x30 [ 0.000000] parse_early_param+0x36/0x4d [ 0.000000] setup_arch+0x336/0x99e [ 0.000000] start_kernel+0x6f/0x4e6 [ 0.000000] x86_64_start_reservations+0x24/0x26 [ 0.000000] x86_64_start_kernel+0x6f/0x72 [ 0.000000] secondary_startup_64+0xa4/0xb0 This patch adds a check to prevent the panic. Signed-off-by: He Zhe Reviewed-by: Marek Szyprowski Cc: stable@vger.kernel.org Signed-off-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman --- kernel/dma/contiguous.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -49,7 +49,11 @@ static phys_addr_t limit_cmdline; static int __init early_cma(char *p) { - pr_debug("%s(%s)\n", __func__, p); + if (!p) { + pr_err("Config string not provided\n"); + return -EINVAL; + } + size_cmdline = memparse(p, &p); if (*p != '@') return 0;