Commit Graph

1997 Commits

Author SHA1 Message Date
Linus Torvalds
7d6beb71da idmapped-mounts-v5.12
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull idmapped mounts from Christian Brauner:
 "This introduces idmapped mounts which has been in the making for some
  time. Simply put, different mounts can expose the same file or
  directory with different ownership. This initial implementation comes
  with ports for fat, ext4 and with Christoph's port for xfs with more
  filesystems being actively worked on by independent people and
  maintainers.

  Idmapping mounts handle a wide range of long standing use-cases. Here
  are just a few:

   - Idmapped mounts make it possible to easily share files between
     multiple users or multiple machines especially in complex
     scenarios. For example, idmapped mounts will be used in the
     implementation of portable home directories in
     systemd-homed.service(8) where they allow users to move their home
     directory to an external storage device and use it on multiple
     computers where they are assigned different uids and gids. This
     effectively makes it possible to assign random uids and gids at
     login time.

   - It is possible to share files from the host with unprivileged
     containers without having to change ownership permanently through
     chown(2).

   - It is possible to idmap a container's rootfs and without having to
     mangle every file. For example, Chromebooks use it to share the
     user's Download folder with their unprivileged containers in their
     Linux subsystem.

   - It is possible to share files between containers with
     non-overlapping idmappings.

   - Filesystem that lack a proper concept of ownership such as fat can
     use idmapped mounts to implement discretionary access (DAC)
     permission checking.

   - They allow users to efficiently changing ownership on a per-mount
     basis without having to (recursively) chown(2) all files. In
     contrast to chown (2) changing ownership of large sets of files is
     instantenous with idmapped mounts. This is especially useful when
     ownership of a whole root filesystem of a virtual machine or
     container is changed. With idmapped mounts a single syscall
     mount_setattr syscall will be sufficient to change the ownership of
     all files.

   - Idmapped mounts always take the current ownership into account as
     idmappings specify what a given uid or gid is supposed to be mapped
     to. This contrasts with the chown(2) syscall which cannot by itself
     take the current ownership of the files it changes into account. It
     simply changes the ownership to the specified uid and gid. This is
     especially problematic when recursively chown(2)ing a large set of
     files which is commong with the aforementioned portable home
     directory and container and vm scenario.

   - Idmapped mounts allow to change ownership locally, restricting it
     to specific mounts, and temporarily as the ownership changes only
     apply as long as the mount exists.

  Several userspace projects have either already put up patches and
  pull-requests for this feature or will do so should you decide to pull
  this:

   - systemd: In a wide variety of scenarios but especially right away
     in their implementation of portable home directories.

         https://systemd.io/HOME_DIRECTORY/

   - container runtimes: containerd, runC, LXD:To share data between
     host and unprivileged containers, unprivileged and privileged
     containers, etc. The pull request for idmapped mounts support in
     containerd, the default Kubernetes runtime is already up for quite
     a while now: https://github.com/containerd/containerd/pull/4734

   - The virtio-fs developers and several users have expressed interest
     in using this feature with virtual machines once virtio-fs is
     ported.

   - ChromeOS: Sharing host-directories with unprivileged containers.

  I've tightly synced with all those projects and all of those listed
  here have also expressed their need/desire for this feature on the
  mailing list. For more info on how people use this there's a bunch of
  talks about this too. Here's just two recent ones:

      https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf
      https://fosdem.org/2021/schedule/event/containers_idmap/

  This comes with an extensive xfstests suite covering both ext4 and
  xfs:

      https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts

  It covers truncation, creation, opening, xattrs, vfscaps, setid
  execution, setgid inheritance and more both with idmapped and
  non-idmapped mounts. It already helped to discover an unrelated xfs
  setgid inheritance bug which has since been fixed in mainline. It will
  be sent for inclusion with the xfstests project should you decide to
  merge this.

  In order to support per-mount idmappings vfsmounts are marked with
  user namespaces. The idmapping of the user namespace will be used to
  map the ids of vfs objects when they are accessed through that mount.
  By default all vfsmounts are marked with the initial user namespace.
  The initial user namespace is used to indicate that a mount is not
  idmapped. All operations behave as before and this is verified in the
  testsuite.

  Based on prior discussions we want to attach the whole user namespace
  and not just a dedicated idmapping struct. This allows us to reuse all
  the helpers that already exist for dealing with idmappings instead of
  introducing a whole new range of helpers. In addition, if we decide in
  the future that we are confident enough to enable unprivileged users
  to setup idmapped mounts the permission checking can take into account
  whether the caller is privileged in the user namespace the mount is
  currently marked with.

  The user namespace the mount will be marked with can be specified by
  passing a file descriptor refering to the user namespace as an
  argument to the new mount_setattr() syscall together with the new
  MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
  of extensibility.

  The following conditions must be met in order to create an idmapped
  mount:

   - The caller must currently have the CAP_SYS_ADMIN capability in the
     user namespace the underlying filesystem has been mounted in.

   - The underlying filesystem must support idmapped mounts.

   - The mount must not already be idmapped. This also implies that the
     idmapping of a mount cannot be altered once it has been idmapped.

   - The mount must be a detached/anonymous mount, i.e. it must have
     been created by calling open_tree() with the OPEN_TREE_CLONE flag
     and it must not already have been visible in the filesystem.

  The last two points guarantee easier semantics for userspace and the
  kernel and make the implementation significantly simpler.

  By default vfsmounts are marked with the initial user namespace and no
  behavioral or performance changes are observed.

  The manpage with a detailed description can be found here:

      1d7b902e28

  In order to support idmapped mounts, filesystems need to be changed
  and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
  patches to convert individual filesystem are not very large or
  complicated overall as can be seen from the included fat, ext4, and
  xfs ports. Patches for other filesystems are actively worked on and
  will be sent out separately. The xfstestsuite can be used to verify
  that port has been done correctly.

  The mount_setattr() syscall is motivated independent of the idmapped
  mounts patches and it's been around since July 2019. One of the most
  valuable features of the new mount api is the ability to perform
  mounts based on file descriptors only.

  Together with the lookup restrictions available in the openat2()
  RESOLVE_* flag namespace which we added in v5.6 this is the first time
  we are close to hardened and race-free (e.g. symlinks) mounting and
  path resolution.

  While userspace has started porting to the new mount api to mount
  proper filesystems and create new bind-mounts it is currently not
  possible to change mount options of an already existing bind mount in
  the new mount api since the mount_setattr() syscall is missing.

  With the addition of the mount_setattr() syscall we remove this last
  restriction and userspace can now fully port to the new mount api,
  covering every use-case the old mount api could. We also add the
  crucial ability to recursively change mount options for a whole mount
  tree, both removing and adding mount options at the same time. This
  syscall has been requested multiple times by various people and
  projects.

  There is a simple tool available at

      https://github.com/brauner/mount-idmapped

  that allows to create idmapped mounts so people can play with this
  patch series. I'll add support for the regular mount binary should you
  decide to pull this in the following weeks:

  Here's an example to a simple idmapped mount of another user's home
  directory:

	u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt

	u1001@f2-vm:/$ ls -al /home/ubuntu/
	total 28
	drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
	drwxr-xr-x 4 root   root   4096 Oct 28 04:00 ..
	-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
	-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
	-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
	-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
	-rw-r--r-- 1 ubuntu ubuntu    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ ls -al /mnt/
	total 28
	drwxr-xr-x  2 u1001 u1001 4096 Oct 28 22:07 .
	drwxr-xr-x 29 root  root  4096 Oct 28 22:01 ..
	-rw-------  1 u1001 u1001 3154 Oct 28 22:12 .bash_history
	-rw-r--r--  1 u1001 u1001  220 Feb 25  2020 .bash_logout
	-rw-r--r--  1 u1001 u1001 3771 Feb 25  2020 .bashrc
	-rw-r--r--  1 u1001 u1001  807 Feb 25  2020 .profile
	-rw-r--r--  1 u1001 u1001    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw-------  1 u1001 u1001 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ touch /mnt/my-file

	u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file

	u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file

	u1001@f2-vm:/$ ls -al /mnt/my-file
	-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file

	u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
	-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file

	u1001@f2-vm:/$ getfacl /mnt/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: mnt/my-file
	# owner: u1001
	# group: u1001
	user::rw-
	user:u1001:rwx
	group::rw-
	mask::rwx
	other::r--

	u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: home/ubuntu/my-file
	# owner: ubuntu
	# group: ubuntu
	user::rw-
	user:ubuntu:rwx
	group::rw-
	mask::rwx
	other::r--"

* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
  xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
  xfs: support idmapped mounts
  ext4: support idmapped mounts
  fat: handle idmapped mounts
  tests: add mount_setattr() selftests
  fs: introduce MOUNT_ATTR_IDMAP
  fs: add mount_setattr()
  fs: add attr_flags_to_mnt_flags helper
  fs: split out functions to hold writers
  namespace: only take read lock in do_reconfigure_mnt()
  mount: make {lock,unlock}_mount_hash() static
  namespace: take lock_mount_hash() directly when changing flags
  nfs: do not export idmapped mounts
  overlayfs: do not mount on top of idmapped mounts
  ecryptfs: do not mount on top of idmapped mounts
  ima: handle idmapped mounts
  apparmor: handle idmapped mounts
  fs: make helpers idmap mount aware
  exec: handle idmapped mounts
  would_dump: handle idmapped mounts
  ...
2021-02-23 13:39:45 -08:00
Xiubo Li
558b4510f6 ceph: defer flushing the capsnap if the Fb is used
If the Fb cap is used it means the current inode is flushing the
dirty data to OSD, just defer flushing the capsnap.

URL: https://tracker.ceph.com/issues/48640
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:52 +01:00
Jeff Layton
a8810cdc00 ceph: allow queueing cap/snap handling after putting cap references
Testing with the fscache overhaul has triggered some lockdep warnings
about circular lock dependencies involving page_mkwrite and the
mmap_lock. It'd be better to do the "real work" without the mmap lock
being held.

Change the skip_checking_caps parameter in __ceph_put_cap_refs to an
enum, and use that to determine whether to queue check_caps, do it
synchronously or not at all. Change ceph_page_mkwrite to do a
ceph_put_cap_refs_async().

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:51 +01:00
Jeff Layton
64f28c627a ceph: clean up inode work queueing
Add a generic function for taking an inode reference, setting the I_WORK
bit and queueing i_work. Turn the ceph_queue_* functions into static
inline wrappers that pass in the right bit.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:51 +01:00
Jeff Layton
64f36da562 ceph: fix flush_snap logic after putting caps
A primary reason for skipping ceph_check_caps after putting the
references was to avoid the locking in ceph_check_caps during a
reconnect. __ceph_put_cap_refs can still call ceph_flush_snaps in that
case though, and that takes many of the same inconvenient locks.

Fix the logic in __ceph_put_cap_refs to skip flushing snaps when the
skip_checking_caps flag is set.

Fixes: e64f44a884 ("ceph: skip checking caps when session reconnecting and releasing reqs")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-02-16 12:09:51 +01:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner
0d56a4518d
stat: handle idmapped mounts
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner
e65ce2a50c
acl: handle idmapped mounts
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.

The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.

In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.

Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner
2f221d6f7b
attr: handle idmapped mounts
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner
47291baa8d
namei: make permission helpers idmapped mount aware
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Ilya Dryomov
4972cf605f libceph, ceph: disambiguate ceph_connection_operations handlers
Since a few years, kernel addresses are no longer included in oops
dumps, at least on x86.  All we get is a symbol name with offset and
size.

This is a problem for ceph_connection_operations handlers, especially
con->ops->dispatch().  All three handlers have the same name and there
is little context to disambiguate between e.g. monitor and OSD clients
because almost everything is inlined.  gdb sneakily stops at the first
matching symbol, so one has to resort to nm and addr2line.

Some of these are already prefixed with mon_, osd_ or mds_.  Let's do
the same for all others.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
2021-01-04 17:31:32 +01:00
Ilya Dryomov
60267ba35c ceph: reencode gid_list when reconnecting
On reconnect, cap and dentry releases are dropped and the fields
that follow must be reencoded into the freed space.  Currently these
are timestamp and gid_list, but gid_list isn't reencoded.  This
results in

  failed to decode message of type 24 v4: End of buffer

errors on the MDS.

While at it, make a change to encode gid_list unconditionally,
without regard to what head/which version was used as a result
of checking whether CEPH_FEATURE_FS_BTIME is supported or not.

URL: https://tracker.ceph.com/issues/48618
Fixes: 4f1ddb1ea8 ("ceph: implement updated ceph_mds_request_head structure")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2020-12-28 20:34:32 +01:00
Ilya Dryomov
ce287162d9 libceph, ceph: make use of __ceph_auth_get_authorizer() in msgr1
This shouldn't cause any functional changes.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00
Ilya Dryomov
cd1a677cad libceph, ceph: implement msgr2.1 protocol (crc and secure modes)
Implement msgr2.1 wire protocol, available since nautilus 14.2.11
and octopus 15.2.5.  msgr2.0 wire protocol is not implemented -- it
has several security, integrity and robustness issues and therefore
considered deprecated.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00
Ilya Dryomov
a5cbd5fc22 libceph, ceph: get and handle cluster maps with addrvecs
In preparation for msgr2, make the cluster send us maps with addrvecs
including both LEGACY and MSGR2 addrs instead of a single LEGACY addr.
This means advertising support for SERVER_NAUTILUS and also some older
features: SERVER_MIMIC, MONENC and MONNAMES.

MONNAMES and MONENC are actually pre-argonaut, we just never updated
ceph_monmap_decode() for them.  Decoding is unconditional, see commit
23c625ce30 ("libceph: assume argonaut on the server side").

SERVER_MIMIC doesn't bear any meaning for the kernel client.

Since ceph_decode_entity_addrvec() is guarded by encoding version
checks (and in msgr2 case it is guarded implicitly by the fact that
server is speaking msgr2), we assume MSG_ADDR2 for it.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00
Ilya Dryomov
285ea34fc8 libceph, ceph: incorporate nautilus cephx changes
- request service tickets together with auth ticket.  Currently we get
  auth ticket via CEPHX_GET_AUTH_SESSION_KEY op and then request service
  tickets via CEPHX_GET_PRINCIPAL_SESSION_KEY op in a separate message.
  Since nautilus, desired service tickets are shared togther with auth
  ticket in CEPHX_GET_AUTH_SESSION_KEY reply.

- propagate session key and connection secret, if any.  In preparation
  for msgr2, update handle_reply() and verify_authorizer_reply() auth
  ops to propagate session key and connection secret.  Since nautilus,
  if secure mode is negotiated, connection secret is shared either in
  CEPHX_GET_AUTH_SESSION_KEY reply (for mons) or in a final authorizer
  reply (for osds and mdses).

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00
Jeff Layton
4f1ddb1ea8 ceph: implement updated ceph_mds_request_head structure
When we added the btime feature in mainline ceph, we had to extend
struct ceph_mds_request_args so that it could be set. Implement the same
in the kernel client.

Rename ceph_mds_request_head with a _old extension, and a union
ceph_mds_request_args_ext to allow for the extended size of the new
header format.

Add the appropriate code to handle both formats in struct
create_request_message and key the behavior on whether the peer supports
CEPH_FEATURE_FS_BTIME.

The gid_list field in the payload is now populated from the saved
credential. For now, we don't add any support for setting the btime via
setattr, but this does enable us to add that in the future.

[ idryomov: break unnecessarily long lines ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Jeff Layton
396bd62c69 ceph: clean up argument lists to __prepare_send_request and __send_request
We can always get the mdsc from the session, so there's no need to pass
it in as a separate argument. Pass the session to __prepare_send_request
as well, to prepare for later patches that will need to access it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Jeff Layton
7fe0cdeb0f ceph: take a cred reference instead of tracking individual uid/gid
Replace req->r_uid/r_gid with an r_cred pointer and take a reference to
that at the point where we previously would sample the two.  Use that to
populate the uid and gid in the header and release the reference when
the request is freed.

This should enable us to later add support for sending supplementary
group lists in MDS requests.

[ idryomov: break unnecessarily long lines ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Jeff Layton
0f51a98361 ceph: don't reach into request header for readdir info
We already have a pointer to the argument struct in req->r_args. Use that
instead of groveling around in the ceph_mds_request_head.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Xiubo Li
968cd14edc ceph: set osdmap epoch for setxattr
When setting the file/dir layout, it may need data pool info. So
in mds server, it needs to check the osdmap. At present, if mds
doesn't find the data pool specified, it will try to get the latest
osdmap. Now if pass the osd epoch for setxattr, the mds server can
only check this epoch of osdmap.

URL: https://tracker.ceph.com/issues/48504
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Colin Ian King
4a756db2a1 ceph: remove redundant assignment to variable i
The variable i is being initialized with a value that is never read
and it is being updated later with a new value in a for-loop.  The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Luis Henriques
dd980fc0d5 ceph: add ceph.caps vxattr
Add a new vxattr that allows userspace to list the caps for a specific
directory or file.

[ jlayton: change format delimiter to '/' ]

Signed-off-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Jeff Layton
bca9fc14c7 ceph: when filling trace, call ceph_get_inode outside of mutexes
Geng Jichao reported a rather complex deadlock involving several
moving parts:

1) readahead is issued against an inode and some of its pages are locked
   while the read is in flight

2) the same inode is evicted from the cache, and this task gets stuck
   waiting for the page lock because of the above readahead

3) another task is processing a reply trace, and looks up the inode
   being evicted while holding the s_mutex. That ends up waiting for the
   eviction to complete

4) a write reply for an unrelated inode is then processed in the
   ceph_con_workfn job. It calls ceph_check_caps after putting wrbuffer
   caps, and that gets stuck waiting on the s_mutex held by 3.

The reply to "1" is stuck behind the write reply in "4", so we deadlock
at that point.

This patch changes the trace processing to call ceph_get_inode outside
of the s_mutex and snap_rwsem, which should break the cycle above.

[ idryomov: break unnecessarily long lines ]

URL: https://tracker.ceph.com/issues/47998
Reported-by: Geng Jichao <gengjichao@jd.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:48 +01:00
Luis Henriques
6646ea1c8e Revert "ceph: allow rename operation under different quota realms"
This reverts commit dffdcd7145.

When doing a rename across quota realms, there's a corner case that isn't
handled correctly.  Here's a testcase:

  mkdir files limit
  truncate files/file -s 10G
  setfattr limit -n ceph.quota.max_bytes -v 1000000
  mv files limit/

The above will succeed because ftruncate(2) won't immediately notify the
MDSs with the new file size, and thus the quota realms stats won't be
updated.

Since the possible fixes for this issue would have a huge performance impact,
the solution for now is to simply revert to returning -EXDEV when doing a cross
quota realms rename.

URL: https://tracker.ceph.com/issues/48203
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
68cbb8056a ceph: fix inode refcount leak when ceph_fill_inode on non-I_NEW inode fails
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Luis Henriques
ccd1acdf1c ceph: downgrade warning from mdsmap decode to debug
While the MDS cluster is unstable and changing state the client may get
mdsmap updates that will trigger warnings:

  [144692.478400] ceph: mdsmap_decode got incorrect state(up:standby-replay)
  [144697.489552] ceph: mdsmap_decode got incorrect state(up:standby-replay)
  [144697.489580] ceph: mdsmap_decode got incorrect state(up:standby-replay)

This patch downgrades these warnings to debug, as they may flood the logs
if the cluster is unstable for a while.

Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Luis Henriques
e5cafce3ad ceph: fix race in concurrent __ceph_remove_cap invocations
A NULL pointer dereference may occur in __ceph_remove_cap with some of the
callbacks used in ceph_iterate_session_caps, namely trim_caps_cb and
remove_session_caps_cb. Those callers hold the session->s_mutex, so they
are prevented from concurrent execution, but ceph_evict_inode does not.

Since the callers of this function hold the i_ceph_lock, the fix is simply
a matter of returning immediately if caps->ci is NULL.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/43272
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
4a357f5069 ceph: pass down the flags to grab_cache_page_write_begin
write_begin operations are passed a flags parameter that we need to
mirror here, so that we don't (e.g.) recurse back into filesystem code
inappropriately.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Xiubo Li
5a9e2f5d55 ceph: add ceph.{cluster_fsid/client_id} vxattrs
These two vxattrs will only exist in local client side, with which
we can easily know which mountpoint the file belongs to and also
they can help locate the debugfs path quickly.

URL: https://tracker.ceph.com/issues/48057
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Xiubo Li
247b1f19db ceph: add status debugfs file
This will help list some useful client side info, like the client
entity address/name and blocklisted status, etc.

URL: https://tracker.ceph.com/issues/48057
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
04fabb1199 ceph: ensure we have Fs caps when fetching dir link count
The link count for a directory is defined as inode->i_subdirs + 2,
(for "." and ".."). i_subdirs is only populated when Fs caps are held.
Ensure we grab Fs caps when fetching the link count for a directory.

[ idryomov: break unnecessarily long line ]

URL: https://tracker.ceph.com/issues/48125
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Xiubo Li
8ba3b8c7fb ceph: send dentry lease metrics to MDS daemon
For the old ceph version, if it received this one metric message
containing the dentry lease metric info, it will just ignore it.

URL: https://tracker.ceph.com/issues/43423
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
81048c00d1 ceph: acquire Fs caps when getting dir stats
We only update the inode's dirstats when we have Fs caps from the MDS.

Declare a new VXATTR_FLAG_DIRSTAT that we set on all dirstats, and have
the vxattr handling code acquire those caps when it's set.

URL: https://tracker.ceph.com/issues/48104
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Patrick Donnelly <pdonnell@redhat.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
06a1ad438b ceph: fix up some warnings on W=1 builds
Convert some decodes into unused variables into skips, and fix up some
non-kerneldoc comment headers to not start with "/**".

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
4ae3713fe4 ceph: queue MDS requests to REJECTED sessions when CLEANRECOVER is set
Ilya noticed that the first access to a blacklisted mount would often
get back -EACCES, but then subsequent calls would be OK. The problem is
in __do_request. If the session is marked as REJECTED, a hard error is
returned instead of waiting for a new session to come into being.

When the session is REJECTED and the mount was done with
recover_session=clean, queue the request to the waiting_for_map queue,
which will be awoken after tearing down the old session. We can only
do this for sync requests though, so check for async ones first and
just let the callers redrive a sync request.

URL: https://tracker.ceph.com/issues/47385
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:47 +01:00
Jeff Layton
dbeec07bc8 ceph: remove timeout on allowing reconnect after blocklisting
30 minutes is a long time to wait, and this makes it difficult to test
the feature by manually blocklisting clients. Remove the timeout
infrastructure and just allow the client to reconnect at will.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
50c9132ddf ceph: add new RECOVER mount_state when recovering session
When recovering a session (a'la recover_session=clean), we want to do
all of the operations that we do on a forced umount, but changing the
mount state to SHUTDOWN is can cause queued MDS requests to fail when
the session comes back. Most of those can idle until the session is
recovered in this situation.

Reserve SHUTDOWN state for forced umount, and make a new RECOVER state
for the forced reconnect situation. Change several tests for equality with
SHUTDOWN to test for that or RECOVER.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
aa5c791053 ceph: make fsc->mount_state an int
This field is an unsigned long currently, which is a bit of a waste on
most arches since this just holds an enum. Make it (signed) int instead.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
dc167e38a0 ceph: don't WARN when removing caps due to blocklisting
We expect to remove dirty caps when the client is blocklisted. Don't
throw a warning in that case.

[ idryomov: break unnecessarily long line ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:46 +01:00
Jeff Layton
62575e270f ceph: check session state after bumping session->s_seq
Some messages sent by the MDS entail a session sequence number
increment, and the MDS will drop certain types of requests on the floor
when the sequence numbers don't match.

In particular, a REQUEST_CLOSE message can cross with one of the
sequence morphing messages from the MDS which can cause the client to
stall, waiting for a response that will never come.

Originally, this meant an up to 5s delay before the recurring workqueue
job kicked in and resent the request, but a recent change made it so
that the client would never resend, causing a 60s stall unmounting and
sometimes a blockisting event.

Add a new helper for incrementing the session sequence and then testing
to see whether a REQUEST_CLOSE needs to be resent, and move the handling
of CEPH_MDS_SESSION_CLOSING into that function. Change all of the
bare sequence counter increments to use the new helper.

Reorganize check_session_state with a switch statement.  It should no
longer be called when the session is CLOSING, so throw a warning if it
ever is (but still handle that case sanely).

[ idryomov: whitespace, pr_err() call fixup ]

URL: https://tracker.ceph.com/issues/47563
Fixes: fa99677342 ("ceph: fix potential mdsc use-after-free crash")
Reported-by: Patrick Donnelly <pdonnell@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-11-04 20:55:49 +01:00
Linus Torvalds
0eac1102e9 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff all over the place (the largest group here is
  Christoph's stat cleanups)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: remove KSTAT_QUERY_FLAGS
  fs: remove vfs_stat_set_lookup_flags
  fs: move vfs_fstatat out of line
  fs: implement vfs_stat and vfs_lstat in terms of vfs_fstatat
  fs: remove vfs_statx_fd
  fs: omfs: use kmemdup() rather than kmalloc+memcpy
  [PATCH] reduce boilerplate in fsid handling
  fs: Remove duplicated flag O_NDELAY occurring twice in VALID_OPEN_FLAGS
  selftests: mount: add nosymfollow tests
  Add a "nosymfollow" mount option.
2020-10-24 12:26:05 -07:00
Jeff Layton
c74d79af90 ceph: comment cleanups and clarifications
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
16d68903f5 ceph: break up send_cap_msg
Push the allocation of the msg and the send into the caller. Rename
the function to encode_cap_msg and make it void return.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
5231198089 ceph: drop separate mdsc argument from __send_cap
We can get it from the session if we need it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Matthew Wilcox (Oracle)
c403c3a2fb ceph: promote to unsigned long long before shifting
On 32-bit systems, this shift will overflow for files larger than 4GB.

Cc: stable@vger.kernel.org
Fixes: 61f6881621 ("ceph: check caps in filemap_fault and page_mkwrite")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
7edf1ec5b2 ceph: don't SetPageError on readpage errors
PageError really only has meaning within a particular subsystem. Nothing
looks at this bit in the core kernel code, and ceph itself doesn't care
about it. Don't bother setting the PageError bit on error.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Ilya Dryomov
f6fbdcd997 ceph: mark ceph_fmt_xattr() as printf-like for better type checking
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
1cc1699070 ceph: fold ceph_update_writeable_page into ceph_write_begin
...and reorganize the loop for better clarity.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00
Jeff Layton
6390987f2f ceph: fold ceph_sync_writepages into writepage_nounlock
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-10-12 15:29:27 +02:00