mnt: Implicitly add MNT_NODEV on remount when it was implicitly added by mount

commit 3e1866410f upstream.

Now that remount is properly enforcing the rule that you can't remove
nodev at least sandstorm.io is breaking when performing a remount.

It turns out that there is an easy intuitive solution implicitly
add nodev on remount when nodev was implicitly added on mount.

Tested-by: Cedric Bosdonnat <cbosdonnat@suse.com>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eric W. Biederman 2014-08-13 01:33:38 -07:00 committed by Greg Kroah-Hartman
parent 46b4fd75fc
commit aad34f76b1
1 changed files with 7 additions and 1 deletions

View File

@ -1966,7 +1966,13 @@ static int do_remount(struct path *path, int flags, int mnt_flags,
}
if ((mnt->mnt.mnt_flags & MNT_LOCK_NODEV) &&
!(mnt_flags & MNT_NODEV)) {
return -EPERM;
/* Was the nodev implicitly added in mount? */
if ((mnt->mnt_ns->user_ns != &init_user_ns) &&
!(sb->s_type->fs_flags & FS_USERNS_DEV_MOUNT)) {
mnt_flags |= MNT_NODEV;
} else {
return -EPERM;
}
}
if ((mnt->mnt.mnt_flags & MNT_LOCK_NOSUID) &&
!(mnt_flags & MNT_NOSUID)) {