From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751625AbdF0OhW (ORCPT ); Tue, 27 Jun 2017 10:37:22 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:55650 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752210AbdF0ON6 (ORCPT ); Tue, 27 Jun 2017 10:13:58 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tobias Wolf , Sergei Shtylyov , linux-mips@linux-mips.org, Ralf Baechle , Amit Pundir Subject: [PATCH 4.9 35/44] of: Add check to of_scan_flat_dt() before accessing initial_boot_params Date: Tue, 27 Jun 2017 16:12:47 +0200 Message-Id: <20170627141110.440433893@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170627141107.865578528@linuxfoundation.org> References: <20170627141107.865578528@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tobias Wolf commit 3ec754410cb3e931a6c4920b1a150f21a94a2bf4 upstream. An empty __dtb_start to __dtb_end section might result in initial_boot_params being null for arch/mips/ralink. This showed that the boot process hangs indefinitely in of_scan_flat_dt(). Signed-off-by: Tobias Wolf Cc: Sergei Shtylyov Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14605/ Signed-off-by: Ralf Baechle Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman --- drivers/of/fdt.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -741,9 +741,12 @@ int __init of_scan_flat_dt(int (*it)(uns const char *pathp; int offset, rc = 0, depth = -1; - for (offset = fdt_next_node(blob, -1, &depth); - offset >= 0 && depth >= 0 && !rc; - offset = fdt_next_node(blob, offset, &depth)) { + if (!blob) + return 0; + + for (offset = fdt_next_node(blob, -1, &depth); + offset >= 0 && depth >= 0 && !rc; + offset = fdt_next_node(blob, offset, &depth)) { pathp = fdt_get_name(blob, offset, NULL); if (*pathp == '/')