From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934479AbbLPRrj (ORCPT ); Wed, 16 Dec 2015 12:47:39 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:50163 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966708AbbLPRkz (ORCPT ); Wed, 16 Dec 2015 12:40:55 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Arnd Bergmann , Ohad Ben-Cohen , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 116/128] remoteproc: avoid stack overflow in debugfs file Date: Wed, 16 Dec 2015 09:39:16 -0800 Message-Id: <1450287568-19808-117-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1450287568-19808-1-git-send-email-kamal@canonical.com> References: <1450287568-19808-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann commit 92792e48e2ae6051af30468a87994b5432da2f06 upstream. Recent gcc versions warn about reading from a negative offset of an on-stack array: drivers/remoteproc/remoteproc_debugfs.c: In function 'rproc_recovery_write': drivers/remoteproc/remoteproc_debugfs.c:167:9: warning: 'buf[4294967295u]' may be used uninitialized in this function [-Wmaybe-uninitialized] I don't see anything in sys_write() that prevents us from being called with a zero 'count' argument, so we should add an extra check in rproc_recovery_write() to prevent the access and avoid the warning. Signed-off-by: Arnd Bergmann Fixes: 2e37abb89a2e ("remoteproc: create a 'recovery' debugfs entry") Signed-off-by: Ohad Ben-Cohen Signed-off-by: Kamal Mostafa --- drivers/remoteproc/remoteproc_debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c index 9d30809..916af50 100644 --- a/drivers/remoteproc/remoteproc_debugfs.c +++ b/drivers/remoteproc/remoteproc_debugfs.c @@ -156,7 +156,7 @@ rproc_recovery_write(struct file *filp, const char __user *user_buf, char buf[10]; int ret; - if (count > sizeof(buf)) + if (count < 1 || count > sizeof(buf)) return count; ret = copy_from_user(buf, user_buf, count); -- 1.9.1