From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755136Ab3LHLux (ORCPT ); Sun, 8 Dec 2013 06:50:53 -0500 Received: from mail-pd0-f170.google.com ([209.85.192.170]:35910 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753483Ab3LHLur (ORCPT ); Sun, 8 Dec 2013 06:50:47 -0500 From: "ethan.zhao" To: konrad.wilk@oracle.com, stefano.stabellini@eu.citrix.com Cc: JBeulich@suse.com, tefano.stabellini@citrix.com, linux-kernel@vger.kernel.org, "ethan.zhao" Subject: [PATCH] xen/p2m: Check d_mmu_debug dentry to void NULL pointer issue Date: Sun, 8 Dec 2013 19:49:16 +0800 Message-Id: <1386503356-1286-1-git-send-email-ethan.kernel@gmail.com> X-Mailer: git-send-email 1.8.3.4 (Apple Git-47) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Should check return value of debugfs_create_dir(), the d_mmu_debug pointer before using it in function xen_p2m_debugfs(). Signed-off-by: ethan.zhao --- arch/x86/xen/p2m.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index a61c7d5..ac17f99 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -1172,8 +1172,13 @@ static int __init xen_p2m_debugfs(void) return -ENOMEM; d_mmu_debug = debugfs_create_dir("mmu", d_xen); + if (!d_mmu_debug) + return -ENOENT; + + if (!debugfs_create_file("p2m", + 0600, d_mmu_debug, NULL, &p2m_dump_fops)) + return -ENOENT; - debugfs_create_file("p2m", 0600, d_mmu_debug, NULL, &p2m_dump_fops); return 0; } fs_initcall(xen_p2m_debugfs); -- 1.8.3.4 (Apple Git-47)