Commit Graph

366 Commits

Author SHA1 Message Date
Linus Torvalds
6bec003528 Merge branch 'for-3.20/bdi' of git://git.kernel.dk/linux-block
Pull backing device changes from Jens Axboe:
 "This contains a cleanup of how the backing device is handled, in
  preparation for a rework of the life time rules.  In this part, the
  most important change is to split the unrelated nommu mmap flags from
  it, but also removing a backing_dev_info pointer from the
  address_space (and inode), and a cleanup of other various minor bits.

  Christoph did all the work here, I just fixed an oops with pages that
  have a swap backing.  Arnd fixed a missing export, and Oleg killed the
  lustre backing_dev_info from staging.  Last patch was from Al,
  unexporting parts that are now no longer needed outside"

* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
  Make super_blocks and sb_lock static
  mtd: export new mtd_mmap_capabilities
  fs: make inode_to_bdi() handle NULL inode
  staging/lustre/llite: get rid of backing_dev_info
  fs: remove default_backing_dev_info
  fs: don't reassign dirty inodes to default_backing_dev_info
  nfs: don't call bdi_unregister
  ceph: remove call to bdi_unregister
  fs: remove mapping->backing_dev_info
  fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
  nilfs2: set up s_bdi like the generic mount_bdev code
  block_dev: get bdev inode bdi directly from the block device
  block_dev: only write bdev inode on close
  fs: introduce f_op->mmap_capabilities for nommu mmap support
  fs: kill BDI_CAP_SWAP_BACKED
  fs: deduplicate noop_backing_dev_info
2015-02-12 13:50:21 -08:00
Trond Myklebust
ea7c38fef0 NFSv4: Ensure we reference the inode for return-on-close in delegreturn
If we have to do a return-on-close in the delegreturn code, then
we must ensure that the inode and super block remain referenced.

Cc: Peng Tao <tao.peng@primarydata.com>
Cc: stable@vger.kernel.org # 3.17.x
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-05 21:31:06 -05:00
Christoph Hellwig
7b14a21389 nfs: don't call bdi_unregister
bdi_destroy already does all the work, and if we delay freeing the
anon bdev we can get away with just that single call.

Addintionally remove the call during mount failure, as
deactivate_super_locked will already call ->kill_sb and clean up
the bdi for us.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-20 14:03:09 -07:00
Anna Schumaker
f08460dc23 NFS: Remove v3 not compiled check from validate_mount_data()
This check is already performed by the module loading code - if the
module can't be found then -EPROTONOSUPPORT will be returned.  Let's
handle v3 this way, too.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-12 13:50:20 -04:00
Scott Mayhew
71a6ec8ac5 nfs: reject changes to resvport and sharecache during remount
Commit c8e47028 made it possible to change resvport/noresvport and
sharecache/nosharecache via a remount operation, neither of which should be
allowed.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Fixes: c8e47028 (nfs: Apply NFS_MOUNT_CMP_FLAGMASK to nfs_compare_remount_data)
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-08-04 17:41:52 -04:00
Fabian Frederick
002160269f NFS: use ARRAY_SIZE instead of sizeof/sizeof[0]
Use macro definition

Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-07-12 18:43:58 -04:00
Mateusz Guzik
a914722f33 NFS: populate ->net in mount data when remounting
Otherwise the kernel oopses when remounting with IPv6 server because
net is dereferenced in dev_get_by_name.

Use net ns of current thread so that dev_get_by_name does not operate on
foreign ns. Changing the address is prohibited anyway so this should not
affect anything.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Cc: linux-nfs@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-10 11:10:29 -04:00
Scott Mayhew
c8e470280a nfs: Apply NFS_MOUNT_CMP_FLAGMASK to nfs_compare_remount_data()
Those flags are obsolete and checking them can incorrectly cause
remount operations to fail.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-05-29 16:46:09 -04:00
Theodore Ts'o
02b9984d64 fs: push sync_filesystem() down to the file system's remount_fs()
Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs().  This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.

However, it's possible that there might be some file systems that are
actually depending on this behavior.  In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Anders Larsen <al@alarsen.net>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org
2014-03-13 10:14:33 -04:00
NeilBrown
9e08ef1afb NFS: correctly report misuse of "migration" mount option.
The current test on valid use of the "migration" mount option can never
report an error as it will only do so if
    mnt->version !=4 && mnt->minor_version != 0
(and some other condition), but if that test would succeed, then the previous
test has already gone-to  out_minorversion_mismatch.

So change the && to an || to get correct semantics.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-11-15 13:41:43 -05:00
Weston Andros Adamson
4d4b69dd84 NFS: add support for multiple sec= mount options
This patch adds support for multiple security options which can be
specified using a colon-delimited list of security flavors (the same
syntax as nfsd's exports file).

This is useful, for instance, when NFSv4.x mounts cross SECINFO
boundaries. With this patch a user can use "sec=krb5i,krb5p"
to mount a remote filesystem using krb5i, but can still cross
into krb5p-only exports.

New mounts will try all security options before failing.  NFSv4.x
SECINFO results will be compared against the sec= flavors to
find the first flavor in both lists or if no match is found will
return -EPERM.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:38:02 -04:00
Weston Andros Adamson
5837f6dfcb NFS: stop using NFS_MOUNT_SECFLAVOUR server flag
Since the parsed sec= flavor is now stored in nfs_server->auth_info,
we no longer need an nfs_server flag to determine if a sec= option was
used.

This flag has not been completely removed because it is still needed for
the (old but still supported) non-text parsed mount options ABI
compatability.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:37:56 -04:00
Weston Andros Adamson
0f5f49b8b3 NFS: cache parsed auth_info in nfs_server
Cache the auth_info structure in nfs_server and pass these values to submounts.

This lays the groundwork for supporting multiple sec= options.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:37:43 -04:00
Weston Andros Adamson
a3f73c27af NFS: separate passed security flavs from selected
When filling parsed_mount_data, store the parsed sec= mount option in
the new struct nfs_auth_info and the chosen flavor in selected_flavor.

This patch lays the groundwork for supporting multiple sec= options.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:36:58 -04:00
Chuck Lever
ce6cda1845 NFS: Add a super_block backpointer to the nfs_server struct
NFS_SB() returns the pointer to an nfs_server struct, given a
pointer to a super_block.  But we have no way to go back the other
way.

Add a super_block backpointer field so that, given an nfs_server
struct, it is easy to get to the filesystem's root dentry.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:24:26 -04:00
Jeff Layton
1966903f8e nfs: fix handling of invalid mount options in nfs_remount
nfs_parse_mount_options returns 0 on error, not -errno.

Reported-by: Karel Zak <kzak@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 14:35:07 -04:00
Jeff Layton
57acc40d73 nfs: reject version and minorversion changes on remount attempts
Reported-by: Eric Doutreleau <edoutreleau@genoscope.cns.fr>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 14:30:23 -04:00
Dave Chinner
1ab6c4997e fs: convert fs shrinkers to new scan/count API
Convert the filesystem shrinkers to use the new API, and standardise some
of the behaviours of the shrinkers at the same time.  For example,
nr_to_scan means the number of objects to scan, not the number of objects
to free.

I refactored the CIFS idmap shrinker a little - it really needs to be
broken up into a shrinker per tree and keep an item count with the tree
root so that we don't need to walk the tree every time the shrinker needs
to count the number of objects in the tree (i.e.  all the time under
memory pressure).

[glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree]
[assorted fixes folded in]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10 18:56:31 -04:00
Linus Torvalds
bf97293eb8 NFS client updates for Linux 3.12
Highlights include:
 
 - Fix NFSv4 recovery so that it doesn't recover lost locks in cases such as
   lease loss due to a network partition, where doing so may result in data
   corruption. Add a kernel parameter to control choice of legacy behaviour
   or not.
 - Performance improvements when 2 processes are writing to the same file.
 - Flush data to disk when an RPCSEC_GSS session timeout is imminent.
 - Implement NFSv4.1 SP4_MACH_CRED state protection to prevent other
   NFS clients from being able to manipulate our lease and file lockingr
   state.
 - Allow sharing of RPCSEC_GSS caches between different rpc clients
 - Fix the broken NFSv4 security auto-negotiation between client and server
 - Fix rmdir() to wait for outstanding sillyrename unlinks to complete
 - Add a tracepoint framework for debugging NFSv4 state recovery issues.
 - Add tracing to the generic NFS layer.
 - Add tracing for the SUNRPC socket connection state.
 - Clean up the rpc_pipefs mount/umount event management.
 - Merge more patches from Chuck in preparation for NFSv4 migration support.
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Merge tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

   - Fix NFSv4 recovery so that it doesn't recover lost locks in cases
     such as lease loss due to a network partition, where doing so may
     result in data corruption.  Add a kernel parameter to control
     choice of legacy behaviour or not.
   - Performance improvements when 2 processes are writing to the same
     file.
   - Flush data to disk when an RPCSEC_GSS session timeout is imminent.
   - Implement NFSv4.1 SP4_MACH_CRED state protection to prevent other
     NFS clients from being able to manipulate our lease and file
     locking state.
   - Allow sharing of RPCSEC_GSS caches between different rpc clients.
   - Fix the broken NFSv4 security auto-negotiation between client and
     server.
   - Fix rmdir() to wait for outstanding sillyrename unlinks to complete
   - Add a tracepoint framework for debugging NFSv4 state recovery
     issues.
   - Add tracing to the generic NFS layer.
   - Add tracing for the SUNRPC socket connection state.
   - Clean up the rpc_pipefs mount/umount event management.
   - Merge more patches from Chuck in preparation for NFSv4 migration
     support"

* tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (107 commits)
  NFSv4: use mach cred for SECINFO_NO_NAME w/ integrity
  NFS: nfs_compare_super shouldn't check the auth flavour unless 'sec=' was set
  NFSv4: Allow security autonegotiation for submounts
  NFSv4: Disallow security negotiation for lookups when 'sec=' is specified
  NFSv4: Fix security auto-negotiation
  NFS: Clean up nfs_parse_security_flavors()
  NFS: Clean up the auth flavour array mess
  NFSv4.1 Use MDS auth flavor for data server connection
  NFS: Don't check lock owner compatability unless file is locked (part 2)
  NFS: Don't check lock owner compatibility in writes unless file is locked
  nfs4: Map NFS4ERR_WRONG_CRED to EPERM
  nfs4.1: Add SP4_MACH_CRED write and commit support
  nfs4.1: Add SP4_MACH_CRED stateid support
  nfs4.1: Add SP4_MACH_CRED secinfo support
  nfs4.1: Add SP4_MACH_CRED cleanup support
  nfs4.1: Add state protection handler
  nfs4.1: Minimal SP4_MACH_CRED implementation
  SUNRPC: Replace pointer values with task->tk_pid and rpc_clnt->cl_clid
  SUNRPC: Add an identifier for struct rpc_clnt
  SUNRPC: Ensure rpc_task->tk_pid is available for tracepoints
  ...
2013-09-09 09:19:15 -07:00
Trond Myklebust
0aea92bf67 NFS: nfs_compare_super shouldn't check the auth flavour unless 'sec=' was set
Also don't worry about obsolete mount flags...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-07 18:38:04 -04:00
Trond Myklebust
19e7b8d240 NFS: Clean up nfs_parse_security_flavors()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-07 16:12:45 -04:00
Trond Myklebust
74c9881162 NFS: Clean up the auth flavour array mess
What is the point of having a 'auth_flavor_len' field, if it is
always set to 1, and can't be used to determine if the user has
selected an auth flavour?
This cleanup goes back to using auth_flavor_len for its original
intended purpose, and gets rid of the ad-hoc replacements.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-07 16:11:24 -04:00
Trond Myklebust
f6de7a39c1 NFSv4: Document the recover_lost_locks kernel parameter
Rename the new 'recover_locks' kernel parameter to 'recover_lost_locks'
and change the default to 'false'. Document why in
Documentation/kernel-parameters.txt

Move the 'recover_lost_locks' kernel parameter to fs/nfs/super.c to
make it easy to backport to kernels prior to 3.6.x, which don't have
a separate NFSv4 module.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-04 12:26:32 -04:00
Scott Mayhew
e890db0104 NFSv4: Fix the sync mount option for nfs4 mounts
The sync mount option stopped working for NFSv4 mounts after commit
c02d7adf8c (NFSv4: Replace nfs4_path_walk() with
FS path lookup in a private namespace).  If MS_SYNCHRONOUS is set in the
super_block that we're cloning from, then it should be set in the new
super_block as well.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-08-07 17:07:41 -04:00
Trond Myklebust
6da1a03436 NFSv4: Refuse mount attempts with proto=udp
RFC3530 disallows the use of udp as a transport protocol for NFSv4.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-08-07 12:37:04 -04:00
Trond Myklebust
959d921f5e Merge branch 'labeled-nfs' into linux-next
* labeled-nfs:
  NFS: Apply v4.1 capabilities to v4.2
  NFS: Add in v4.2 callback operation
  NFS: Make callbacks minor version generic
  Kconfig: Add Kconfig entry for Labeled NFS V4 client
  NFS: Extend NFS xattr handlers to accept the security namespace
  NFS: Client implementation of Labeled-NFS
  NFS: Add label lifecycle management
  NFS:Add labels to client function prototypes
  NFSv4: Extend fattr bitmaps to support all 3 words
  NFSv4: Introduce new label structure
  NFSv4: Add label recommended attribute and NFSv4 flags
  NFSv4.2: Added NFS v4.2 support to the NFS client
  SELinux: Add new labeling type native labels
  LSM: Add flags field to security_sb_set_mnt_opts for in kernel mount data.
  Security: Add Hook to test if the particular xattr is part of a MAC model.
  Security: Add hook to calculate context based on a negative dentry.
  NFS: Add NFSv4.2 protocol constants

Conflicts:
	fs/nfs/nfs4proc.c
2013-06-28 16:29:51 -04:00
Jeff Layton
9111c95b07 nfs: have NFSv3 try server-specified auth flavors in turn
The current scheme is to try and pick the auth flavor that the server
prefers. In some cases though, we may find that we're not actually
able to use that auth flavor later. For instance, the server may
prefer an AUTH_GSS flavor, but we may not be able to get GSSAPI creds.

The current code just gives up at that point. Change it instead to
try the ->create_server call using each of the different authflavors
in the server's list if one was not specified at mount time. Once
we have a successful ->create_server call, return the result. Only
give up and return error if all attempts fail.

Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-28 15:52:37 -04:00
Jeff Layton
fb9b02fda0 nfs: have nfs_mount fake up a auth_flavs list when the server didn't provide it
Instead of handling this as a special case in the auth-selection code,
we can simply fake up an auth_flavs list when the server doesn't
provide it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-28 15:51:51 -04:00
Jeff Layton
294ae81d4f nfs: move server_authlist into nfs_try_mount_request
In a later patch we're going to want to cycle over this list and attempt
to call ->create_server for each different flavor until one succeeds.
Move the list allocation to the stack of nfs_try_mount_request() and
pass a pointer to it and its length to nfs_request_mount().

Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-28 15:49:49 -04:00
Jeff Layton
d17540c61b nfs: refactor "need_mount" code out of nfs_try_mount
This looks like pointless refactoring for now, but we'll flesh out
the need_mount case a little more in a later patch.

Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-28 15:49:27 -04:00
David Quigley
aa9c266962 NFS: Client implementation of Labeled-NFS
This patch implements the client transport and handling support for labeled
NFS. The patch adds two functions to encode and decode the security label
recommended attribute which makes use of the LSM hooks added earlier. It also
adds code to grab the label from the file attribute structures and encode the
label to be sent back to the server.

Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-08 16:20:16 -04:00
David Quigley
a09df2ca23 NFSv4: Extend fattr bitmaps to support all 3 words
The fattr handling bitmap code only uses the first two fattr words sofar. This
patch adds the 3rd word to being sent but doesn't populate it yet.

Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-08 16:20:14 -04:00
Steve Dickson
42c2c4249c NFSv4.2: Added NFS v4.2 support to the NFS client
This enable NFSv4.2 support. To enable this code the
CONFIG_NFS_V4_2 Kconfig define needs to be set and
the -o v4.2 mount option need to be used.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-08 16:20:13 -04:00
David Quigley
649f6e7718 LSM: Add flags field to security_sb_set_mnt_opts for in kernel mount data.
There is no way to differentiate if a text mount option is passed from user
space or the kernel. A flags field is being added to the
security_sb_set_mnt_opts hook to allow for in kernel security flags to be sent
to the LSM for processing in addition to the text options received from mount.
This patch also updated existing code to fix compilation errors.

Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-06-08 16:20:12 -04:00
Chuck Lever
eb54d43707 NFS: Fix security flavor negotiation with legacy binary mounts
Darrick J. Wong <darrick.wong@oracle.com> reports:
> I have a kvm-based testing setup that netboots VMs over NFS, the
> client end of which seems to have broken somehow in 3.10-rc1.  The
> server's exports file looks like this:
>
> /storage/mtr/x64	192.168.122.0/24(ro,sync,no_root_squash,no_subtree_check)
>
> On the client end (inside the VM), the initrd runs the following
> command to try to mount the rootfs over NFS:
>
> # mount -o nolock -o ro -o retrans=10 192.168.122.1:/storage/mtr/x64/ /root
>
> (Note: This is the busybox mount command.)
>
> The mount fails with -EINVAL.

Commit 4580a92d44 "NFS: Use server-recommended security flavor by
default (NFSv3)" introduced a behavior regression for NFS mounts
done via a legacy binary mount(2) call.

Ensure that a default security flavor is specified for legacy binary
mount requests, since they do not invoke nfs_select_flavor() in the
kernel.

Busybox uses klibc's nfsmount command, which performs NFS mounts
using the legacy binary mount data format.  /sbin/mount.nfs is not
affected by this regression.

Reported-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-05-30 16:31:34 -04:00
Linus Torvalds
8cbc95ee74 More NFS client bugfixes for 3.10
- Ensure that we match the 'sec=' mount flavour against the server list
 - Fix the NFSv4 byte range locking in the presence of delegations
 - Ensure that we conform to the NFSv4.1 spec w.r.t. freeing lock stateids
 - Fix a pNFS data server connection race
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Merge tag 'nfs-for-3.10-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull more NFS client bugfixes from Trond Myklebust:

 - Ensure that we match the 'sec=' mount flavour against the server list

 - Fix the NFSv4 byte range locking in the presence of delegations

 - Ensure that we conform to the NFSv4.1 spec w.r.t.  freeing lock
   stateids

 - Fix a pNFS data server connection race

* tag 'nfs-for-3.10-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS4.1 Fix data server connection race
  NFSv3: match sec= flavor against server list
  NFSv4.1: Ensure that we free the lock stateid on the server
  NFSv4: Convert nfs41_free_stateid to use an asynchronous RPC call
  SUNRPC: Don't spam syslog with "Pseudoflavor not found" messages
  NFSv4.x: Fix handling of partially delegated locks
2013-05-09 10:24:54 -07:00
Weston Andros Adamson
d497ab9751 NFSv3: match sec= flavor against server list
Older linux clients match the 'sec=' mount option flavor against the server's
flavor list (if available) and return EPERM if the specified flavor or AUTH_NULL
(which "matches" any flavor) is not found.

Recent changes skip this step and allow the vfs mount even though no operations
will succeed, creating a 'dud' mount.

This patch reverts back to the old behavior of matching specified flavors
against the server list and also returns EPERM when no sec= is specified and
none of the flavors returned by the server are supported by the client.

Example of behavior change:

the server's /etc/exports:

/export/krb5      *(sec=krb5,rw,no_root_squash)

old client behavior:

$ uname -a
Linux one.apikia.fake 3.8.8-202.fc18.x86_64 #1 SMP Wed Apr 17 23:25:17 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
$ sudo mount -v -o sec=sys,vers=3 zero:/export/krb5 /mnt
mount.nfs: timeout set for Sun May  5 17:32:04 2013
mount.nfs: trying text-based options 'sec=sys,vers=3,addr=192.168.100.10'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying 192.168.100.10 prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying 192.168.100.10 prog 100005 vers 3 prot UDP port 20048
mount.nfs: mount(2): Permission denied
mount.nfs: access denied by server while mounting zero:/export/krb5

recently changed behavior:

$ uname -a
Linux one.apikia.fake 3.9.0-testing+ #2 SMP Fri May 3 20:29:32 EDT 2013 x86_64 x86_64 x86_64 GNU/Linux
$ sudo mount -v -o sec=sys,vers=3 zero:/export/krb5 /mnt
mount.nfs: timeout set for Sun May  5 17:37:17 2013
mount.nfs: trying text-based options 'sec=sys,vers=3,addr=192.168.100.10'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: trying 192.168.100.10 prog 100003 vers 3 prot TCP port 2049
mount.nfs: prog 100005, trying vers=3, prot=17
mount.nfs: trying 192.168.100.10 prog 100005 vers 3 prot UDP port 20048
$ ls /mnt
ls: cannot open directory /mnt: Permission denied
$ sudo ls /mnt
ls: cannot open directory /mnt: Permission denied
$ sudo df /mnt
df: ‘/mnt’: Permission denied
df: no file systems processed
$ sudo umount /mnt
$

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-05-06 17:24:36 -04:00
Linus Torvalds
2e1deaad1e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem update from James Morris:
 "Just some minor updates across the subsystem"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  ima: eliminate passing d_name.name to process_measurement()
  TPM: Retry SaveState command in suspend path
  tpm/tpm_i2c_infineon: Add small comment about return value of __i2c_transfer
  tpm/tpm_i2c_infineon.c: Add OF attributes type and name to the of_device_id table entries
  tpm_i2c_stm_st33: Remove duplicate inclusion of header files
  tpm: Add support for new Infineon I2C TPM (SLB 9645 TT 1.2 I2C)
  char/tpm: Convert struct i2c_msg initialization to C99 format
  drivers/char/tpm/tpm_ppi: use strlcpy instead of strncpy
  tpm/tpm_i2c_stm_st33: formatting and white space changes
  Smack: include magic.h in smackfs.c
  selinux: make security_sb_clone_mnt_opts return an error on context mismatch
  seccomp: allow BPF_XOR based ALU instructions.
  Fix NULL pointer dereference in smack_inode_unlink() and smack_inode_rmdir()
  Smack: add support for modification of existing rules
  smack: SMACK_MAGIC to include/uapi/linux/magic.h
  Smack: add missing support for transmute bit in smack_str_from_perm()
  Smack: prevent revoke-subject from failing when unseen label is written to it
  tomoyo: use DEFINE_SRCU() to define tomoyo_ss
  tomoyo: use DEFINE_SRCU() to define tomoyo_ss
2013-04-30 16:27:51 -07:00
Linus Torvalds
8728f986fe NFS client bugfixes and cleanups for 3.10
- NLM: stable fix for NFSv2/v3 blocking locks
 - NFSv4.x: stable fixes for the delegation recall error handling code
 - NFSv4.x: Security flavour negotiation fixes and cleanups by Chuck Lever
 - SUNRPC: A number of RPCSEC_GSS fixes and cleanups also from Chuck
 - NFSv4.x assorted state management and reboot recovery bugfixes
 - NFSv4.1: In cases where we have already looked up a file, and hold a
   valid filehandle, use the new open-by-filehandle operation instead of
   opening by name.
 - Allow the NFSv4.1 callback thread to freeze
 - NFSv4.x: ensure that file unlock waits for readahead to complete
 - NFSv4.1: ensure that the RPC layer doesn't override the NFS session
   table size negotiation by limiting the number of slots.
 - NFSv4.x: Fix SETATTR spec compatibility issues
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Merge tag 'nfs-for-3.10-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes and cleanups from Trond Myklebust:

 - NLM: stable fix for NFSv2/v3 blocking locks

 - NFSv4.x: stable fixes for the delegation recall error handling code

 - NFSv4.x: Security flavour negotiation fixes and cleanups by Chuck
   Lever

 - SUNRPC: A number of RPCSEC_GSS fixes and cleanups also from Chuck

 - NFSv4.x assorted state management and reboot recovery bugfixes

 - NFSv4.1: In cases where we have already looked up a file, and hold a
   valid filehandle, use the new open-by-filehandle operation instead of
   opening by name.

 - Allow the NFSv4.1 callback thread to freeze

 - NFSv4.x: ensure that file unlock waits for readahead to complete

 - NFSv4.1: ensure that the RPC layer doesn't override the NFS session
   table size negotiation by limiting the number of slots.

 - NFSv4.x: Fix SETATTR spec compatibility issues

* tag 'nfs-for-3.10-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (67 commits)
  NFSv4: Warn once about servers that incorrectly apply open mode to setattr
  NFSv4: Servers should only check SETATTR stateid open mode on size change
  NFSv4: Don't recheck permissions on open in case of recovery cached open
  NFSv4.1: Don't do a delegated open for NFS4_OPEN_CLAIM_DELEG_CUR_FH modes
  NFSv4.1: Use the more efficient open_noattr call for open-by-filehandle
  NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONE
  NFSv4: Ensure that we clear the NFS_OPEN_STATE flag when appropriate
  LOCKD: Ensure that nlmclnt_block resets block->b_status after a server reboot
  NFSv4: Ensure the LOCK call cannot use the delegation stateid
  NFSv4: Use the open stateid if the delegation has the wrong mode
  nfs: Send atime and mtime as a 64bit value
  NFSv4: Record the OPEN create mode used in the nfs4_opendata structure
  NFSv4.1: Set the RPC_CLNT_CREATE_INFINITE_SLOTS flag for NFSv4.1 transports
  SUNRPC: Allow rpc_create() to request that TCP slots be unlimited
  SUNRPC: Fix a livelock problem in the xprt->backlog queue
  NFSv4: Fix handling of revoked delegations by setattr
  NFSv4 release the sequence id in the return on close case
  nfs: remove unnecessary check for NULL inode->i_flock from nfs_delegation_claim_locks
  NFS: Ensure that NFS file unlock waits for readahead to complete
  NFS: Add functionality to allow waiting on all outstanding reads to complete
  ...
2013-04-30 11:28:08 -07:00
Chuck Lever
4580a92d44 NFS: Use server-recommended security flavor by default (NFSv3)
Since commit ec88f28d in 2009, checking if the user-specified flavor
is in the server's flavor list has been the source of a few
noticeable regressions (now fixed), but there is one that is still
vexing.

An NFS server can list AUTH_NULL in its flavor list, which suggests
a client should try to mount the server with the flavor of the
client's choice, but the server will squash all accesses.  In some
cases, our client fails to mount a server because of this check,
when the mount could have proceeded successfully.

Skip this check if the user has specified "sec=" on the mount
command line.  But do consult the server-provided flavor list to
choose a security flavor if no sec= option is specified on the mount
command.

If a server lists Kerberos pseudoflavors before "sys" in its export
options, our client now chooses Kerberos over AUTH_UNIX for mount
points, when no security flavor is specified by the mount command.
This could be surprising to some administrators or users, who would
then need to have Kerberos credentials to access the export.

Or, a client administrator may not have enabled rpc.gssd.  In this
case, auth_rpcgss.ko might still be loadable, which is enough for
the new logic to choose Kerberos over AUTH_UNIX.  But the mount
would fail since no GSS context can be created without rpc.gssd
running.

To retain the use of AUTH_UNIX by default:

  o  The server administrator can ensure that "sys" is listed before
     Kerberos flavors in its export security options (see
     exports(5)),

  o  The client administrator can explicitly specify "sec=sys" on
     its mount command line (see nfs(5)),

  o  The client administrator can use "Sec=sys" in an appropriate
     section of /etc/nfsmount.conf (see nfsmount.conf(5)), or

  o  The client administrator can blacklist auth_rpcgss.ko.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-04-04 17:01:01 -04:00
Jeff Layton
094f7b69ea selinux: make security_sb_clone_mnt_opts return an error on context mismatch
I had the following problem reported a while back. If you mount the
same filesystem twice using NFSv4 with different contexts, then the
second context= option is ignored. For instance:

    # mount server:/export /mnt/test1
    # mount server:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0
    # ls -dZ /mnt/test1
    drwxrwxrwt. root root system_u:object_r:nfs_t:s0       /mnt/test1
    # ls -dZ /mnt/test2
    drwxrwxrwt. root root system_u:object_r:nfs_t:s0       /mnt/test2

When we call into SELinux to set the context of a "cloned" superblock,
it will currently just bail out when it notices that we're reusing an
existing superblock. Since the existing superblock is already set up and
presumably in use, we can't go overwriting its context with the one from
the "original" sb. Because of this, the second context= option in this
case cannot take effect.

This patch fixes this by turning security_sb_clone_mnt_opts into an int
return operation. When it finds that the "new" superblock that it has
been handed is already set up, it checks to see whether the contexts on
the old superblock match it. If it does, then it will just return
success, otherwise it'll return -EBUSY and emit a printk to tell the
admin why the second mount failed.

Note that this patch may cause casualties. The NFSv4 code relies on
being able to walk down to an export from the pseudoroot. If you mount
filesystems that are nested within one another with different contexts,
then this patch will make those mounts fail in new and "exciting" ways.

For instance, suppose that /export is a separate filesystem on the
server:

    # mount server:/ /mnt/test1
    # mount salusa:/export /mnt/test2 -o context=system_u:object_r:tmp_t:s0
    mount.nfs: an incorrect mount option was specified

...with the printk in the ring buffer. Because we *might* eventually
walk down to /mnt/test1/export, the mount is denied due to this patch.
The second mount needs the pseudoroot superblock, but that's already
present with the wrong context.

OTOH, if we mount these in the reverse order, then both mounts work,
because the pseudoroot superblock created when mounting /export is
discarded once that mount is done. If we then however try to walk into
that directory, the automount fails for the similar reasons:

    # cd /mnt/test1/scratch/
    -bash: cd: /mnt/test1/scratch: Device or resource busy

The story I've gotten from the SELinux folks that I've talked to is that
this is desirable behavior. In SELinux-land, mounting the same data
under different contexts is wrong -- there can be only one.

Cc: Steve Dickson <steved@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-04-02 11:30:13 +11:00
Eric W. Biederman
fa7614ddd6 fs: Readd the fs module aliases.
I had assumed that the only use of module aliases for filesystems
prior to "fs: Limit sys_mount to only request filesystem modules."
was in request_module.  It turns out I was wrong.  At least mkinitcpio
in Arch linux uses these aliases.

So readd the preexising aliases, to keep from breaking userspace.

Userspace eventually will have to follow and use the same aliases the
kernel does.  So at some point we may be delete these aliases without
problems.  However that day is not today.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-12 18:55:21 -07:00
Eric W. Biederman
7f78e03513 fs: Limit sys_mount to only request filesystem modules.
Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-03 19:36:31 -08:00
Linus Torvalds
b6669737d3 Merge branch 'for-3.9' of git://linux-nfs.org/~bfields/linux
Pull nfsd changes from J Bruce Fields:
 "Miscellaneous bugfixes, plus:

   - An overhaul of the DRC cache by Jeff Layton.  The main effect is
     just to make it larger.  This decreases the chances of intermittent
     errors especially in the UDP case.  But we'll need to watch for any
     reports of performance regressions.

   - Containerized nfsd: with some limitations, we now support
     per-container nfs-service, thanks to extensive work from Stanislav
     Kinsbursky over the last year."

Some notes about conflicts, since there were *two* non-data semantic
conflicts here:

 - idr_remove_all() had been added by a memory leak fix, but has since
   become deprecated since idr_destroy() does it for us now.

 - xs_local_connect() had been added by this branch to make AF_LOCAL
   connections be synchronous, but in the meantime Trond had changed the
   calling convention in order to avoid a RCU dereference.

There were a couple of more obvious actual source-level conflicts due to
the hlist traversal changes and one just due to code changes next to
each other, but those were trivial.

* 'for-3.9' of git://linux-nfs.org/~bfields/linux: (49 commits)
  SUNRPC: make AF_LOCAL connect synchronous
  nfsd: fix compiler warning about ambiguous types in nfsd_cache_csum
  svcrpc: fix rpc server shutdown races
  svcrpc: make svc_age_temp_xprts enqueue under sv_lock
  lockd: nlmclnt_reclaim(): avoid stack overflow
  nfsd: enable NFSv4 state in containers
  nfsd: disable usermode helper client tracker in container
  nfsd: use proper net while reading "exports" file
  nfsd: containerize NFSd filesystem
  nfsd: fix comments on nfsd_cache_lookup
  SUNRPC: move cache_detail->cache_request callback call to cache_read()
  SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() function
  SUNRPC: rework cache upcall logic
  SUNRPC: introduce cache_detail->cache_request callback
  NFS: simplify and clean cache library
  NFS: use SUNRPC cache creation and destruction helper for DNS cache
  nfsd4: free_stid can be static
  nfsd: keep a checksum of the first 256 bytes of request
  sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer
  sunrpc: fix comment in struct xdr_buf definition
  ...
2013-02-28 18:02:55 -08:00
Linus Torvalds
d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Jeff Layton
ecf3d1f1aa vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
The following set of operations on a NFS client and server will cause

    server# mkdir a
    client# cd a
    server# mv a a.bak
    client# sleep 30  # (or whatever the dir attrcache timeout is)
    client# stat .
    stat: cannot stat `.': Stale NFS file handle

Obviously, we should not be getting an ESTALE error back there since the
inode still exists on the server. The problem is that the lookup code
will call d_revalidate on the dentry that "." refers to, because NFS has
FS_REVAL_DOT set.

nfs_lookup_revalidate will see that the parent directory has changed and
will try to reverify the dentry by redoing a LOOKUP. That of course
fails, so the lookup code returns ESTALE.

The problem here is that d_revalidate is really a bad fit for this case.
What we really want to know at this point is whether the inode is still
good or not, but we don't really care what name it goes by or whether
the dcache is still valid.

Add a new d_op->d_weak_revalidate operation and have complete_walk call
that instead of d_revalidate. The intent there is to allow for a
"weaker" d_revalidate that just checks to see whether the inode is still
good. This is also gives us an opportunity to kill off the FS_REVAL_DOT
special casing.

[AV: changed method name, added note in porting, fixed confusion re
having it possibly called from RCU mode (it won't be)]

Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26 02:46:09 -05:00
Jeff Layton
5976687a2b sunrpc: move address copy/cmp/convert routines and prototypes from clnt.h to addr.h
These routines are used by server and client code, so having them in a
separate header would be best.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-05 09:41:14 -05:00
Trond Myklebust
322b2b9032 Revert "NFS: add nfs_sb_deactive_async to avoid deadlock"
This reverts commit 324d003b0c.

The deadlock turned out to be caused by a workqueue limitation that has
now been worked around in the RPC code (see comment in rpc_free_task).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-02-01 10:13:48 -05:00
Trond Myklebust
dee972b967 NFS: Fix error reporting in nfs_xdev_mount
Currently, nfs_xdev_mount converts all errors from clone_server() to
ENOMEM, which can then leak to userspace (for instance to 'mount'). Fix that.
Also ensure that if nfs_fs_mount_common() returns an error, we
don't dprintk(0)...

The regression originated in commit 3d176e3fe4
(NFS: Use nfs_fs_mount_common() for xdev mounts)

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 3.5]
2013-01-27 15:51:15 -05:00
Xi Wang
e25fbe380c nfs: fix null checking in nfs_get_option_str()
The following null pointer check is broken.

	*option = match_strdup(args);
	return !option;

The pointer `option' must be non-null, and thus `!option' is always false.
Use `!*option' instead.

The bug was introduced in commit c5cb09b6f8 ("Cleanup: Factor out some
cut-and-paste code.").

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-01-04 10:54:43 -05:00