From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753010AbbJMBKR (ORCPT ); Mon, 12 Oct 2015 21:10:17 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:43544 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752800AbbJMBJP (ORCPT ); Mon, 12 Oct 2015 21:09:15 -0400 From: Stephen Boyd To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Viresh Kumar Subject: [PATCH 3/4] debugfs: Add read-only/write-only size_t file ops Date: Mon, 12 Oct 2015 18:09:11 -0700 Message-Id: <1444698552-12369-4-git-send-email-sboyd@codeaurora.org> X-Mailer: git-send-email 2.6.1.134.g26caae2 In-Reply-To: <1444698552-12369-1-git-send-email-sboyd@codeaurora.org> References: <1444698552-12369-1-git-send-email-sboyd@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There aren't any read-only or write-only size_t file ops, but there is a caller of debugfs_create_size_t() that calls it with mode equal to 0400. This leads to the possibility of userspace modifying the file, so let's use the newly created debugfs_create_mode() helper here to fix this. Signed-off-by: Stephen Boyd --- fs/debugfs/file.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index f69d42efe4b8..e8e73aebe6b8 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -352,6 +352,8 @@ static int debugfs_size_t_get(void *data, u64 *val) } DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set, "%llu\n"); /* %llu and %zu are more or less the same */ +DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_ro, debugfs_size_t_get, NULL, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_wo, NULL, debugfs_size_t_set, "%llu\n"); /** * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value @@ -366,7 +368,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set, struct dentry *debugfs_create_size_t(const char *name, umode_t mode, struct dentry *parent, size_t *value) { - return debugfs_create_file(name, mode, parent, value, &fops_size_t); + return debugfs_create_mode(name, mode, parent, value, &fops_size_t, + &fops_size_t_ro, &fops_size_t_wo); } EXPORT_SYMBOL_GPL(debugfs_create_size_t); -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project