From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3340693-1520825225-2-2765522620397882213 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES unknown, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1520825225; b=utzhD4a6GCmUD7rG6QUJv3zEDY7MXWtC9SbmI+Z5pcGdsm/ 0sWW43cYPuwkUUHLdpDEAaBsLF1BgkipZywNwZkvf8G4rjlXiuaqh6Mf6HL9risF qbw5k6X/eYqhkGOUsuTrHrLX4HjMe+b88Oilgh8zw2KMbl29Y32bv2BfQtz6x4Dr Jqt38V0Sh2m6KdIdmQ0JNuqvqmgnOuHBlYOt5O5T0qob91i+N88UvxlGE4jGZbFc WBT2PM16iJlBhMZuWZhSkvse3bQsGrcVP3rJu1pZYLLkhVoGdw61fBaSrjMJrPTM rxohSCvNN5+76DDoPg7IhtuUrGQlqqvIu8EfH8Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1520825225; bh=UFCQYtfB9U78kushcE1 nWQnVZZrxrkf6sjoU86NI6pI=; b=RXGKTb8DtbxM4hNWRWmtc299N7FUvsfFkY3 TvU0YAStkJzuZcEvlzsf+77nfL//t5xGyCgq+zTMufvfBsjYalUBiuB/E6eyES1j MfqJhupyM+h4io7jQf7OLyNzfBuZC1+Illxe/4sSuQXJE6aaCuGRiWN2C8ZCtQr1 ANXdEMqwvPVqy5dZn9SJd6L8CY6DB6FLcRpzWTXgT9SVk58EWJ01OtTjzf6Bjw2S CkxwxfPlP7Cm//pXVcs5wj0RsYEGEU4GkVfyjnsBFC16nVuh3c1YsgvEvTvVdOui LhcgdIi0ctdWjOHC3h9gHLONySiV52SVTs7EWvql6WVADmhjCkg== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932687AbeCLDZ1 (ORCPT ); Sun, 11 Mar 2018 23:25:27 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41219 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932681AbeCLDHn (ORCPT ); Sun, 11 Mar 2018 23:07:43 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Tim Gardner" , "Alexander Viro" Date: Mon, 12 Mar 2018 03:03:34 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 022/104] fs: namespace: suppress 'may be used uninitialized' warnings In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.2.101-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Tim Gardner commit b8850d1fa8e2f6653e57daf6d08e58c5f5eb2c85 upstream. The gcc version 4.9.1 compiler complains Even though it isn't possible for these variables to not get initialized before they are used. fs/namespace.c: In function ‘SyS_mount’: fs/namespace.c:2720:8: warning: ‘kernel_dev’ may be used uninitialized in this function [-Wmaybe-uninitialized] ret = do_mount(kernel_dev, kernel_dir->name, kernel_type, flags, ^ fs/namespace.c:2699:8: note: ‘kernel_dev’ was declared here char *kernel_dev; ^ fs/namespace.c:2720:8: warning: ‘kernel_type’ may be used uninitialized in this function [-Wmaybe-uninitialized] ret = do_mount(kernel_dev, kernel_dir->name, kernel_type, flags, ^ fs/namespace.c:2697:8: note: ‘kernel_type’ was declared here char *kernel_type; ^ Fix the warnings by simplifying copy_mount_string() as suggested by Al Viro. Cc: Alexander Viro Signed-off-by: Tim Gardner Signed-off-by: Al Viro Signed-off-by: Ben Hutchings --- fs/compat.c | 10 ++++++---- fs/internal.h | 2 +- fs/namespace.c | 26 ++++++++------------------ 3 files changed, 15 insertions(+), 23 deletions(-) --- a/fs/compat.c +++ b/fs/compat.c @@ -797,8 +797,9 @@ asmlinkage long compat_sys_mount(const c char *dir_page; int retval; - retval = copy_mount_string(type, &kernel_type); - if (retval < 0) + kernel_type = copy_mount_string(type); + retval = PTR_ERR(kernel_type); + if (IS_ERR(kernel_type)) goto out; dir_page = getname(dir_name); @@ -806,8 +807,9 @@ asmlinkage long compat_sys_mount(const c if (IS_ERR(dir_page)) goto out1; - retval = copy_mount_string(dev_name, &kernel_dev); - if (retval < 0) + kernel_dev = copy_mount_string(dev_name); + retval = PTR_ERR(kernel_dev); + if (IS_ERR(kernel_dev)) goto out2; retval = copy_mount_options(data, &data_page); --- a/fs/internal.h +++ b/fs/internal.h @@ -60,7 +60,7 @@ extern int check_unsafe_exec(struct linu * namespace.c */ extern int copy_mount_options(const void __user *, unsigned long *); -extern int copy_mount_string(const void __user *, char **); +extern char *copy_mount_string(const void __user *); extern unsigned int mnt_get_count(struct vfsmount *mnt); extern struct vfsmount *__lookup_mnt(struct vfsmount *, struct dentry *, int); --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2253,21 +2253,9 @@ int copy_mount_options(const void __user return 0; } -int copy_mount_string(const void __user *data, char **where) +char *copy_mount_string(const void __user *data) { - char *tmp; - - if (!data) { - *where = NULL; - return 0; - } - - tmp = strndup_user(data, PAGE_SIZE); - if (IS_ERR(tmp)) - return PTR_ERR(tmp); - - *where = tmp; - return 0; + return data ? strndup_user(data, PAGE_SIZE) : NULL; } /* @@ -2535,8 +2523,9 @@ SYSCALL_DEFINE5(mount, char __user *, de char *kernel_dev; unsigned long data_page; - ret = copy_mount_string(type, &kernel_type); - if (ret < 0) + kernel_type = copy_mount_string(type); + ret = PTR_ERR(kernel_type); + if (IS_ERR(kernel_type)) goto out_type; kernel_dir = getname(dir_name); @@ -2545,8 +2534,9 @@ SYSCALL_DEFINE5(mount, char __user *, de goto out_dir; } - ret = copy_mount_string(dev_name, &kernel_dev); - if (ret < 0) + kernel_dev = copy_mount_string(dev_name); + ret = PTR_ERR(kernel_dev); + if (IS_ERR(kernel_dev)) goto out_dev; ret = copy_mount_options(data, &data_page);