Commit Graph

1067 Commits

Author SHA1 Message Date
Suresh Jayaraman
3694b91a59 cifs: update README to include details about 'fsc' option
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-11 17:11:28 +00:00
Linus Torvalds
5f248c9c25 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
  no need for list_for_each_entry_safe()/resetting with superblock list
  Fix sget() race with failing mount
  vfs: don't hold s_umount over close_bdev_exclusive() call
  sysv: do not mark superblock dirty on remount
  sysv: do not mark superblock dirty on mount
  btrfs: remove junk sb_dirt change
  BFS: clean up the superblock usage
  AFFS: wait for sb synchronization when needed
  AFFS: clean up dirty flag usage
  cifs: truncate fallout
  mbcache: fix shrinker function return value
  mbcache: Remove unused features
  add f_flags to struct statfs(64)
  pass a struct path to vfs_statfs
  update VFS documentation for method changes.
  All filesystems that need invalidate_inode_buffers() are doing that explicitly
  convert remaining ->clear_inode() to ->evict_inode()
  Make ->drop_inode() just return whether inode needs to be dropped
  fs/inode.c:clear_inode() is gone
  fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
  ...

Fix up trivial conflicts in fs/nilfs2/super.c
2010-08-10 11:26:52 -07:00
Christoph Hellwig
1b9474635e cifs: truncate fallout
Remove the calls to inode_newsize_ok given that we already did it as
part of inode_change_ok in the beginning of cifs_setattr_(no)unix.

No need to call ->truncate if cifs doesn't have one, so remove the
explicit call in cifs_vmtruncate, and replace the calls to vmtruncate
with truncate_setsize which is vmtruncate minus inode_newsize_ok
and the call to ->truncate.

Rename cifs_vmtruncate to cifs_setsize to match the new calling conventions.

Question 1:  why does cifs do the pagecache munging and i_size update twice
	for each setattr call, once opencoded in cifs_vmtruncate, and once
	using the VFS helpers?
Question 2: what is supposed to be protected by i_lock in cifs_vmtruncate?
	Do we need it around the call to inode_change_ok?

[AV: fixed build breakage]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:48:48 -04:00
Al Viro
b57922d97f convert remaining ->clear_inode() to ->evict_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:48:37 -04:00
Al Viro
45321ac543 Make ->drop_inode() just return whether inode needs to be dropped
... and let iput_final() do the actual eviction or retention

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:48:35 -04:00
Christoph Hellwig
db78b877f7 always call inode_change_ok early in ->setattr
Make sure we call inode_change_ok before doing any changes in ->setattr,
and make sure to call it even if our fs wants to ignore normal UNIX
permissions, but use the ATTR_FORCE to skip those.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:38 -04:00
Christoph Hellwig
1025774ce4 remove inode_setattr
Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:37 -04:00
Linus Torvalds
1fc7995d19 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  [DNS RESOLVER] Minor typo correction
  DNS: Fixes for the DNS query module
  cifs: Include linux/err.h for IS_ERR and PTR_ERR
  DNS: Make AFS go to the DNS for AFSDB records for unknown cells
  DNS: Separate out CIFS DNS Resolver code
  cifs: account for new creduid=0x%x parameter in spnego upcall string
  cifs: reduce false positives with inode aliasing serverino autodisable
  CIFS: Make cifs_convert_address() take a const src pointer and a length
  cifs: show features compiled in as part of DebugData
  cifs: update README

Fix up trivial conflicts in fs/cifs/cifsfs.c due to workqueue changes
2010-08-07 12:54:46 -07:00
Linus Torvalds
3b7433b8a8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
  workqueue: mark init_workqueues() as early_initcall()
  workqueue: explain for_each_*cwq_cpu() iterators
  fscache: fix build on !CONFIG_SYSCTL
  slow-work: kill it
  gfs2: use workqueue instead of slow-work
  drm: use workqueue instead of slow-work
  cifs: use workqueue instead of slow-work
  fscache: drop references to slow-work
  fscache: convert operation to use workqueue instead of slow-work
  fscache: convert object to use workqueue instead of slow-work
  workqueue: fix how cpu number is stored in work->data
  workqueue: fix mayday_mask handling on UP
  workqueue: fix build problem on !CONFIG_SMP
  workqueue: fix locking in retry path of maybe_create_worker()
  async: use workqueue for worker pool
  workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
  workqueue: implement unbound workqueue
  workqueue: prepare for WQ_UNBOUND implementation
  libata: take advantage of cmwq and remove concurrency limitations
  workqueue: fix worker management invocation without pending works
  ...

Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
2010-08-07 12:42:58 -07:00
Wang Lei
1a4240f476 DNS: Separate out CIFS DNS Resolver code
Separate out the DNS resolver key type from the CIFS filesystem into its own
module so that it can be made available for general use, including the AFS
filesystem module.

This facility makes it possible for the kernel to upcall to userspace to have
it issue DNS requests, package up the replies and present them to the kernel
in a useful form.  The kernel is then able to cache the DNS replies as keys
can be retained in keyrings.

Resolver keys are of type "dns_resolver" and have a case-insensitive
description that is of the form "[<type>:]<domain_name>".  The optional <type>
indicates the particular DNS lookup and packaging that's required.  The
<domain_name> is the query to be made.

If <type> isn't given, a basic hostname to IP address lookup is made, and the
result is stored in the key in the form of a printable string consisting of a
comma-separated list of IPv4 and IPv6 addresses.

This key type is supported by userspace helpers driven from /sbin/request-key
and configured through /etc/request-key.conf.  The cifs.upcall utility is
invoked for UNC path server name to IP address resolution.

The CIFS functionality is encapsulated by the dns_resolve_unc_to_ip() function,
which is used to resolve a UNC path to an IP address for CIFS filesystem.  This
part remains in the CIFS module for now.

See the added Documentation/networking/dns_resolver.txt for more information.

Signed-off-by: Wang Lei <wang840925@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:51 +00:00
Jeff Layton
ba5dadbf4e cifs: account for new creduid=0x%x parameter in spnego upcall string
The commit that added the creduid=0x%x parameter failed to increase the
buffer allocation to account for it.

Reported-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:50 +00:00
Jeff Layton
5acfec2502 cifs: reduce false positives with inode aliasing serverino autodisable
It turns out that not all directory inodes with dentries on the
i_dentry list are unusable here. We only consider them unusable if they
are still hashed or if they have a root dentry attached.

Full disclosure -- this check is inherently racy. There's nothing that
stops someone from slapping a new dentry onto this inode just after
this check, or hashing an existing one that's already attached. So,
this is really a "best effort" thing to work around misbehaving servers.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:50 +00:00
David Howells
67b7626a05 CIFS: Make cifs_convert_address() take a const src pointer and a length
Make cifs_convert_address() take a const src pointer and a length so that all
the strlen() calls in their can be cut out and to make it unnecessary to modify
the src string.

Also return the data length from dns_resolve_server_name_to_ip() so that a
strlen() can be cut out of cifs_compose_mount_options() too.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:50 +00:00
Suresh Jayaraman
f579903ef3 cifs: show features compiled in as part of DebugData
Fixed the nit pointed out by Jeff.

From: Suresh Jayaraman <sjayaraman@suse.de>
Subject: [PATCH 1/2] cifs: show features compiled in as part of DebugData

This patch adds the features that are compiled in to the CIFS debugging data
as shown below:

	$cat /proc/fs/cifs/DebugData
	Display Internal CIFS Data Structures for Debugging
	---------------------------------------------------
	CIFS Version 1.64
	Features: dfs fscache posix spnego xattr
	Active VFS Requests: 0
	...

This patch provides a definitive way to tell what features are currently
enabled in the running kernel. This could also help debugging.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:50 +00:00
Suresh Jayaraman
95c99904f6 cifs: update README
Update the README file to reflect that now DebugData shows all
the features enabled.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Cc: Jeff Layton <jlayton@redhat.com>
--
 fs/cifs/README |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05 17:17:50 +00:00
Jeff Layton
cb76d5e250 cifs: fsc should not default to "on"
I'm not sure why this was merged with this flag hardcoded on, but it
seems quite dangerous. Turn it off.

Also, mount.cifs hands unrecognized options off to the kernel so there
should be no need for changes there in order to support this.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:41 +00:00
Steve French
f67909cf80 [CIFS] remove redundant path walking in dfs_do_refmount
Reviewed-by: Dave Howells <dhowells@redhat.com>
Signed-off-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:40 +00:00
Jeff Layton
f636a34802 cifs: ignore the "mand", "nomand" and "_netdev" mount options
These are all handled by the userspace mount programs, but older versions
of mount.cifs also handed them off to the kernel. Ignore them.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:40 +00:00
Jeff Layton
3572d2857f cifs: map NT_STATUS_ERROR_WRITE_PROTECTED to -EROFS
Seems like a more sensible mapping than -EIO.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:40 +00:00
Jeff Layton
f30b9c1184 cifs: don't allow cifs_iget to match inodes of the wrong type
If the type is different from what we think it should be, then don't
match the existing inode.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:39 +00:00
Steve French
9f841593ff [CIFS] relinquish fscache cookie before freeing CIFSTconInfo
Doh, fix a use after free bug.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:39 +00:00
Jeff Layton
3e4b3e1f68 cifs: add separate cred_uid field to sesInfo
Right now, there's no clear separation between the uid that owns the
credentials used to do the mount and the overriding owner of the files
on that mount.

Add a separate cred_uid field that is set to the real uid
of the mount user. Unlike the linux_uid, the uid= option does not
override this parameter. The parm is sent to cifs.upcall, which can then
preferentially use the creduid= parm instead of the uid= parm for
finding credentials.

This is not the only way to solve this. We could try to do all of this
in kernel instead by having a module parameter that affects what gets
passed in the uid= field of the upcall. That said, we have a lot more
flexibility to change things in userspace so I think it probably makes
sense to do it this way.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:39 +00:00
Kulikov Vasiliy
f55fdcca6b fs: cifs: check kmalloc() result
If kmalloc() fails exit with -ENOMEM.

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:39 +00:00
Steve French
0ccd48025f [CIFS] Missing ifdef
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:38 +00:00
Steve French
d0e6f44e6c [CIFS] Missing line from previous commit
CC: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:38 +00:00
Steve French
c5e04a3e49 [CIFS] Fix build break when CONFIG_CIFS_FSCACHE disabled
CC: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:38 +00:00
Suresh Jayaraman
fa1df75d4d cifs: add mount option to enable local caching
Add a mount option 'fsc' to enable local caching on CIFS.

I considered adding a separate debug bit for caching, but it appears that
debugging would be relatively easier with the normal CIFS_INFO level.

As the cifs-utils (userspace) changes are not done yet, this patch enables
'fsc' by default to enable testing.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:37 +00:00
Suresh Jayaraman
56698236e1 cifs: read pages from FS-Cache
Read pages from a FS-Cache data storage object into a CIFS inode.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:37 +00:00
Suresh Jayaraman
9dc06558c2 cifs: store pages into local cache
Store pages from an CIFS inode into the data storage object associated with
that inode.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:37 +00:00
Suresh Jayaraman
85f2d6b44d cifs: FS-Cache page management
Takes care of invalidation and release of FS-Cache marked pages and also
invalidation of the FsCache page flag when the inode is removed.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:36 +00:00
Suresh Jayaraman
9451a9a52f cifs: define inode-level cache object and register them
Define inode-level data storage objects (managed by cifsInodeInfo structs).
Each inode-level object is created in a super-block level object and is itself
a data storage object in to which pages from the inode are stored.

The inode object is keyed by UniqueId. The coherency data being used is
LastWriteTime, LastChangeTime and end of file reported by the server.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:36 +00:00
Suresh Jayaraman
d03382ce9a cifs: define superblock-level cache index objects and register them
Define superblock-level cache index objects (managed by cifsTconInfo structs).
Each superblock object is created in a server-level index object and in itself
an index into which inode-level objects are inserted.

The superblock object is keyed by sharename. The UniqueId/IndexNumber is used to
validate that the exported share is the same since we accessed it last time.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:36 +00:00
Jeff Layton
8913007e67 cifs: remove unused cifsUidInfo struct
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:35 +00:00
Jeff Layton
4ff67b720c cifs: clean up cifs_find_smb_ses (try #2)
This patch replaces the earlier patch by the same name. The only
difference is that MAX_PASSWORD_SIZE has been increased to attempt to
match the limits that windows enforces.

Do a better job of matching sessions by authtype. Matching by username
for a Kerberos session is incorrect, and anonymous sessions need special
handling.

Also, in the case where we do match by username, we also need to match
by password. That ensures that someone else doesn't "borrow" an existing
session without needing to know the password.

Finally, passwords can be longer than 16 bytes. Bump MAX_PASSWORD_SIZE
to 512 to match the size that the userspace mount helper allows.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:35 +00:00
Jeff Layton
daf5b0b6f3 cifs: match secType when searching for existing tcp session
The secType is a per-tcp session entity, but the current routine doesn't
verify that it is acceptible when attempting to match an existing TCP
session.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:35 +00:00
Jeff Layton
4515148ef7 cifs: move address comparison into separate function
Move the address comparator out of cifs_find_tcp_session and into a
separate function for cleanliness. Also change the argument to
that function to a "struct sockaddr" pointer. Passing pointers to
sockaddr_storage is a little odd since that struct is generally for
declaring static storage.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:34 +00:00
Jeff Layton
50d971602a cifs: set the port in sockaddr in a more clearly defined fashion
This patch should replace the patch I sent a couple of weeks ago to
set the port in cifs_convert_address.

Currently we set this in cifs_find_tcp_session, but that's more of a
side effect than anything. Add a new function called cifs_fill_sockaddr.
Have it call cifs_convert_address and then set the port.

This also allows us to skip passing in the port as a separate parm to
cifs_find_tcp_session.

Also, change cifs_convert_address take a struct sockaddr * rather than
void * to make it clearer how this function should be called.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:34 +00:00
Suresh Jayaraman
488f1d2d6c cifs: define server-level cache index objects and register them
Define server-level cache index objects (as managed by TCP_ServerInfo structs)
and register then with FS-Cache. Each server object is created in the CIFS
top-level index object and is itself an index into which superblock-level
objects are inserted.

The server objects are now keyed by {IPaddress,family,port} tuple.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:34 +00:00
Suresh Jayaraman
f579cf3cfd cifs: register CIFS for caching
Define CIFS for FS-Cache and register for caching. Upon registration the
top-level index object cookie will be stuck to the netfs definition by
FS-Cache.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:33 +00:00
Joe Perches
c21dfb699f fs/cifs: Remove unnecessary casts of private_data
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:33 +00:00
Suresh Jayaraman
3feb41cff8 cifs: add kernel config option for CIFS Client caching support
Add a kernel config option to enable local caching for CIFS.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:33 +00:00
Suresh Jayaraman
c6332e237f cifs: remove unused ip_address field in struct TCP_Server_Info
The ip_address field is not used and seems redundant as there is union addr
already and I don't see any future use as well.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:33 +00:00
Suresh Jayaraman
e4317ceca2 cifs: remove an potentially confusing, obsolete comment
The recent commit 6ca9f3bae8 modified the code so
that filp is full instantiated whenever the file is created and passed back.
The below comment is no longer true, remove it.

Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:32 +00:00
Suresh Jayaraman
abd2e44dca cifs: guard cifsglob.h against multiple inclusion
Add conditional compile macros to guard the header file against multiple
inclusion.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-02 12:40:32 +00:00
David Howells
51c20fcced CIFS: Remove __exit mark from cifs_exit_dns_resolver()
Remove the __exit mark from cifs_exit_dns_resolver() as it's called by the
module init routine in case of error, and so may have been discarded during
linkage.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-30 18:56:09 -07:00
Tejun Heo
9b64697246 cifs: use workqueue instead of slow-work
Workqueue can now handle high concurrency.  Use system_nrt_wq
instead of slow-work.

* Updated is_valid_oplock_break() to not call cifs_oplock_break_put()
  as advised by Steve French.  It might cause deadlock.  Instead,
  reference is increased after queueing succeeded and
  cifs_oplock_break() briefly grabs GlobalSMBSeslock before putting
  the cfile to make sure it doesn't put before the matching get is
  finished.

* Anton Blanchard reported that cifs conversion was using now gone
  system_single_wq.  Use system_nrt_wq which provides non-reentrance
  guarantee which is enough and much better.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Steve French <sfrench@samba.org>
Cc: Anton Blanchard <anton@samba.org>
2010-07-22 22:59:15 +02:00
David Howells
4c0c03ca54 CIFS: Fix a malicious redirect problem in the DNS lookup code
Fix the security problem in the CIFS filesystem DNS lookup code in which a
malicious redirect could be installed by a random user by simply adding a
result record into one of their keyrings with add_key() and then invoking a
CIFS CFS lookup [CVE-2010-2524].

This is done by creating an internal keyring specifically for the caching of
DNS lookups.  To enforce the use of this keyring, the module init routine
creates a set of override credentials with the keyring installed as the thread
keyring and instructs request_key() to only install lookup result keys in that
keyring.

The override is then applied around the call to request_key().

This has some additional benefits when a kernel service uses this module to
request a key:

 (1) The result keys are owned by root, not the user that caused the lookup.

 (2) The result keys don't pop up in the user's keyrings.

 (3) The result keys don't come out of the quota of the user that caused the
     lookup.

The keyring can be viewed as root by doing cat /proc/keys:

2a0ca6c3 I-----     1 perm 1f030000     0     0 keyring   .dns_resolver: 1/4

It can then be listed with 'keyctl list' by root.

	# keyctl list 0x2a0ca6c3
	1 key in keyring:
	726766307: --alswrv     0     0 dns_resolver: foo.bar.com

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve French <smfrench@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-22 09:42:40 -07:00
Jeff Layton
8a224d4894 cifs: remove bogus first_time check in NTLMv2 session setup code
This bug appears to be the result of a cut-and-paste mistake from the
NTLMv1 code. The function to generate the MAC key was commented out, but
not the conditional above it. The conditional then ended up causing the
session setup key not to be copied to the buffer unless this was the
first session on the socket, and that made all but the first NTLMv2
session setup fail.

Fix this by removing the conditional and all of the commented clutter
that made it difficult to see.

Cc: Stable <stable@kernel.org>
Reported-by: Gunther Deschner <gdeschne@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2010-06-16 13:40:18 -04:00
Jeff Layton
47c78b7f40 cifs: don't call cifs_new_fileinfo unless cifs_open succeeds
It's currently possible for cifs_open to fail after it has already
called cifs_new_fileinfo. In that situation, the new fileinfo will be
leaked as the caller doesn't call fput. That in turn leads to a busy
inodes after umount problem since the fileinfo holds an extra inode
reference now. Shuffle cifs_open around a bit so that it only calls
cifs_new_fileinfo if it's going to succeed.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
2010-06-16 13:40:17 -04:00
Suresh Jayaraman
d9d5d8df95 cifs: don't ignore cifs_posix_open_inode_helper return value
...and ensure that we propagate the error back to avoid any surprises.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
2010-06-16 13:40:17 -04:00