From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:23794 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932915AbcFCVjm (ORCPT ); Fri, 3 Jun 2016 17:39:42 -0400 From: Sasha Levin To: stable@vger.kernel.org, stable-commits@vger.kernel.org Cc: Mikulas Patocka , Mikulas Patocka , Linus Torvalds , Sasha Levin Subject: [added to the 4.1 stable tree] hpfs: fix remount failure when there are no options changed Date: Fri, 3 Jun 2016 17:37:09 -0400 Message-Id: <1464989831-16666-134-git-send-email-sasha.levin@oracle.com> In-Reply-To: <1464989831-16666-1-git-send-email-sasha.levin@oracle.com> References: <1464989831-16666-1-git-send-email-sasha.levin@oracle.com> Sender: stable-owner@vger.kernel.org List-ID: From: Mikulas Patocka This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 44d51706b4685f965cd32acde3fe0fcc1e6198e8 ] Commit ce657611baf9 ("hpfs: kstrdup() out of memory handling") checks if the kstrdup function returns NULL due to out-of-memory condition. However, if we are remounting a filesystem with no change to filesystem-specific options, the parameter data is NULL. In this case, kstrdup returns NULL (because it was passed NULL parameter), although no out of memory condition exists. The mount syscall then fails with ENOMEM. This patch fixes the bug. We fail with ENOMEM only if data is non-NULL. The patch also changes the call to replace_mount_options - if we didn't pass any filesystem-specific options, we don't call replace_mount_options (thus we don't erase existing reported options). Fixes: ce657611baf9 ("hpfs: kstrdup() out of memory handling") Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/hpfs/super.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c index 8685c65..03b2c9c 100644 --- a/fs/hpfs/super.c +++ b/fs/hpfs/super.c @@ -428,7 +428,7 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) struct hpfs_sb_info *sbi = hpfs_sb(s); char *new_opts = kstrdup(data, GFP_KERNEL); - if (!new_opts) + if (data && !new_opts) return -ENOMEM; sync_filesystem(s); @@ -466,7 +466,8 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) if (!(*flags & MS_RDONLY)) mark_dirty(s, 1); - replace_mount_options(s, new_opts); + if (new_opts) + replace_mount_options(s, new_opts); hpfs_unlock(s); return 0; -- 2.5.0