From: Rob Landley <rob@landley.net>
To: linux-kernel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>,
"Eric W. Biederman" <ebiederm@xmission.com>
Subject: [PATCH 1/5] initmpfs: replace MS_NOUSER in initramfs
Date: Sat, 29 Jun 2013 13:12:14 -0700 (PDT) [thread overview]
Message-ID: <1372536729.850656@landley.net> (raw)
In-Reply-To: <1372536729.850447@landley.net>
From: Rob Landley <rob@landley.net>
Mounting MS_NOUSER prevents --bind mounts from rootfs. Prevent new rootfs
mounts with a different mechanism that doesn't affect bind mounts.
Signed-off-by: Rob Landley <rob@landley.net>
---
fs/ramfs/inode.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index c24f1e1..14b9c35 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -247,7 +247,14 @@ struct dentry *ramfs_mount(struct file_system_type *fs_type,
static struct dentry *rootfs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
- return mount_nodev(fs_type, flags|MS_NOUSER, data, ramfs_fill_super);
+ static int once;
+
+ if (once)
+ return ERR_PTR(-ENODEV);
+ else
+ once++;
+
+ return mount_nodev(fs_type, flags, data, ramfs_fill_super);
}
static void ramfs_kill_sb(struct super_block *sb)
next prev parent reply other threads:[~2013-06-29 20:12 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-29 20:12 [PATCH 0/5] initmpfs: use tmpfs instead of ramfs for rootfs Rob Landley
2013-06-29 20:12 ` Rob Landley [this message]
2013-06-30 1:15 ` [PATCH 1/5] initmpfs: replace MS_NOUSER in initramfs Eric W. Biederman
2013-06-30 2:45 ` Rob Landley
2013-06-30 3:09 ` Rob Landley
2013-06-29 20:12 ` [PATCH 2/5] initmpfs: Move bdi setup from init_rootfs to init_ramfs Rob Landley
2013-06-29 20:12 ` [PATCH 3/5] initmpfs: Move rootfs code from fs/ramfs/ to init/ Rob Landley
2013-06-29 20:12 ` [PATCH 4/5] initmpfs: Make rootfs use tmpfs when CONFIG_TMPFS enabled Rob Landley
2013-06-29 20:12 ` [PATCH 5/5] initmpfs: Use initramfs if rootfstype= or root= specified Rob Landley
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1372536729.850656@landley.net \
--to=rob@landley.net \
--cc=ebiederm@xmission.com \
--cc=linux-kernel@vger.kernel.org \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox