Commit Graph

1201 Commits

Author SHA1 Message Date
Nick Piggin b1e6a015a5 fs: change d_hash for rcu-walk
Change d_hash so it may be called from lock-free RCU lookups. See similar
patch for d_compare for details.

For in-tree filesystems, this is just a mechanical change.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:20 +11:00
Nick Piggin 621e155a35 fs: change d_compare for rcu-walk
Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.

For in-tree filesystems, this is just a mechanical change.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:19 +11:00
Nick Piggin 79eb4dde74 cifs: dont overwrite dentry name in d_revalidate
Use vfat's method for dealing with negative dentries to preserve case,
rather than overwrite dentry name in d_revalidate, which is a bit ugly
and also gets in the way of doing lock-free path walking.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:18 +11:00
Suresh Jayaraman 545c988b20 cifs: remove bogus remapping of error in cifs_filldir()
As the FIXME points out correctly, now filldir() itself returns -EOVERFLOW if
it not possible to represent the inode number supplied by the filesystem in
the field provided by userspace.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-08 18:47:54 +00:00
Jeff Layton 7d161b7f41 cifs: allow calling cifs_build_path_to_root on incomplete cifs_sb
It's possible that cifs_mount will call cifs_build_path_to_root on a
newly instantiated cifs_sb. In that case, it's likely that the
master_tlink pointer has not yet been instantiated.

Fix this by having cifs_build_path_to_root take a cifsTconInfo pointer
as well, and have the caller pass that in.

Reported-and-Tested-by: Robbert Kouprie <robbert@exx.nl>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-07 19:25:37 +00:00
Jeff Layton 03ceace5c6 cifs: fix check of error return from is_path_accessable
This function will return 0 if everything went ok. Commit 9d002df4
however added a block of code after the following check for
rc == -EREMOTE. With that change and when rc == 0, doing the
"goto mount_fail_check" here skips that code, leaving the tlink_tree
and master_tlink pointer unpopulated. That causes an oops later
in cifs_root_iget.

Reported-and-Tested-by: Robbert Kouprie <robbert@exx.nl>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-07 19:17:59 +00:00
Jeff Layton 8846399968 cifs: remove Local_System_Name
...this string is zeroed out and nothing ever changes it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-06 22:45:19 +00:00
Jeff Layton 79df1baeec cifs: fix use of CONFIG_CIFS_ACL
Some of the code under CONFIG_CIFS_ACL is dependent upon code under
CONFIG_CIFS_EXPERIMENTAL, but the Kconfig options don't reflect that
dependency. Move more of the ACL code out from under
CONFIG_CIFS_EXPERIMENTAL and under CONFIG_CIFS_ACL.

Also move find_readable_file out from other any sort of Kconfig
option and make it a function normally compiled in.

Reported-and-Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-06 20:22:39 +00:00
Suresh Jayaraman 6d20e8406f cifs: add attribute cache timeout (actimeo) tunable
Currently, the attribute cache timeout for CIFS is hardcoded to 1 second. This
means that the client might have to issue a QPATHINFO/QFILEINFO call every 1
second to verify if something has changes, which seems too expensive. On the
other hand, if the timeout is hardcoded to a higher value, workloads that
expect strict cache coherency might see unexpected results.

Making attribute cache timeout as a tunable will allow us to make a tradeoff
between performance and cache metadata correctness depending on the
application/workload needs.

Add 'actimeo' tunable that can be used to tune the attribute cache timeout.
The default timeout is set to 1 second. Also, display actimeo option value in
/proc/mounts.

It appears to me that 'actimeo' and the proposed (but not yet merged)
'strictcache' option cannot coexist, so care must be taken that we reset the
other option if one of them is set.

Changes since last post:
   - fix option parsing and handle possible values correcly

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-12-02 19:32:11 +00:00
Jeff Layton ba03864872 cifs: fix parsing of hostname in dfs referrals
The DFS referral parsing code does a memchr() call to find the '\\'
delimiter that separates the hostname in the referral UNC from the
sharename. It then uses that value to set the length of the hostname via
pointer subtraction.  Instead of subtracting the start of the hostname
however, it subtracts the start of the UNC, which causes the code to
pass in a hostname length that is 2 bytes too long.

Regression introduced in commit 1a4240f4.

Reported-and-Tested-by: Robbert Kouprie <robbert@exx.nl>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Wang Lei <wang840925@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 20:44:05 +00:00
Suresh Jayaraman 476428f8c3 cifs: display fsc in /proc/mounts
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 05:51:49 +00:00
Suresh Jayaraman b81209de24 cifs: enable fscache iff fsc mount option is used explicitly
Currently, if CONFIG_CIFS_FSCACHE is set, fscache is enabled on files opened
as read-only irrespective of the 'fsc' mount option. Fix this by enabling
fscache only if 'fsc' mount option is specified explicitly.

Remove an extraneous cFYI debug message and fix a typo while at it.

Reported-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 05:49:32 +00:00
Suresh Jayaraman 607a569da4 cifs: allow fsc mount option only if CONFIG_CIFS_FSCACHE is set
Currently, it is possible to specify 'fsc' mount option even if
CONFIG_CIFS_FSCACHE has not been set. The option is being ignored silently
while the user fscache functionality to work. Fix this by raising error when
the CONFIG option is not set.

Reported-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 05:49:28 +00:00
Shirish Pargaonkar fbeba8bb16 cifs: Handle extended attribute name cifs_acl to generate cifs acl blob (try #4)
Add extended attribute name system.cifs_acl

Get/generate cifs/ntfs acl blob and hand over to the invoker however
it wants to parse/process it under experimental configurable option CIFS_ACL.

Do not get CIFS/NTFS ACL for xattr for attribute system.posix_acl_access

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 05:49:24 +00:00
Shirish Pargaonkar 78415d2d30 cifs: Misc. cleanup in cifsacl handling [try #4]
Change the name of function mode_to_acl to mode_to_cifs_acl.

Handle return code in functions mode_to_cifs_acl and
cifs_acl_to_fattr.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30 05:49:17 +00:00
Suresh Jayaraman 523fb8c867 cifs: trivial comment fix for cifs_invalidate_mapping
Only the callers check whether the invalid_mapping flag is set and not
cifs_invalidate_mapping().

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-29 17:48:16 +00:00
Steve French 362d31297f [CIFS] fs/cifs/Kconfig: CIFS depends on CRYPTO_HMAC
linux-2.6.37-rc1: I compiled a kernel with CIFS which subsequently
failed with an error indicating it couldn't initialize crypto module
"hmacmd5".  CONFIG_CRYPTO_HMAC=y fixed the problem.

This patch makes CIFS depend on CRYPTO_HMAC in kconfig.

Signed-off-by: Jody Bruchon<jody@nctritech.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-14 03:34:30 +00:00
Jeff Layton 59c55ba1fb cifs: don't take extra tlink reference in initiate_cifs_search
It's possible for initiate_cifs_search to be called on a filp that
already has private_data attached. If this happens, we'll end up
calling cifs_sb_tlink, taking an extra reference to the tlink and
attaching that to the cifsFileInfo. This leads to refcount leaks
that manifest as a "stuck" cifsd at umount time.

Fix this by only looking up the tlink for the cifsFile on the filp's
first pass through this function. When called on a filp that already
has cifsFileInfo associated with it, just use the tlink reference
that it already owns.

This patch fixes samba.org bug 7792:

    https://bugzilla.samba.org/show_bug.cgi?id=7792

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-13 03:26:17 +00:00
Shirish Pargaonkar 987b21d7d9 cifs: Percolate error up to the caller during get/set acls [try #4]
Modify get/set_cifs_acl* calls to reutrn error code and percolate the
error code up to the caller.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-11 03:54:36 +00:00
Oskar Schirmer a7851ce73b cifs: fix another memleak, in cifs_root_iget
cifs_root_iget allocates full_path through
cifs_build_path_to_root, but fails to kfree it upon
cifs_get_inode_info* failure.

Make all failure exit paths traverse clean up
handling at the end of the function.

Signed-off-by: Oskar Schirmer <oskar@scara.com>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Cc: stable@kernel.org
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-11 03:40:13 +00:00
Jeff Layton ebe2e91e00 cifs: fix potential use-after-free in cifs_oplock_break_put
cfile may very well be freed after the cifsFileInfo_put. Make sure we
have a valid pointer to the superblock for cifs_sb_deactive.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-10 15:37:17 +00:00
Suresh Jayaraman 3565bd46b1 cifs: fix a memleak in cifs_setattr_nounix()
Andrew Hendry reported a kmemleak warning in 2.6.37-rc1 while editing a
text file with gedit over cifs.

unreferenced object 0xffff88022ee08b40 (size 32):
  comm "gedit", pid 2524, jiffies 4300160388 (age 2633.655s)
  hex dump (first 32 bytes):
    5c 2e 67 6f 75 74 70 75 74 73 74 72 65 61 6d 2d  \.goutputstream-
    35 42 41 53 4c 56 00 de 09 00 00 00 2c 26 78 ee  5BASLV......,&x.
  backtrace:
    [<ffffffff81504a4d>] kmemleak_alloc+0x2d/0x60
    [<ffffffff81136e13>] __kmalloc+0xe3/0x1d0
    [<ffffffffa0313db0>] build_path_from_dentry+0xf0/0x230 [cifs]
    [<ffffffffa031ae1e>] cifs_setattr+0x9e/0x770 [cifs]
    [<ffffffff8115fe90>] notify_change+0x170/0x2e0
    [<ffffffff81145ceb>] sys_fchmod+0x10b/0x140
    [<ffffffff8100c172>] system_call_fastpath+0x16/0x1b
    [<ffffffffffffffff>] 0xffffffffffffffff

The commit 1025774c that removed inode_setattr() seems to have introduced this
memleak by returning early without freeing 'full_path'.

Reported-by: Andrew Hendry <andrew.hendry@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-09 15:17:53 +00:00
Jeff Layton 618763958b cifs: make cifs_ioctl handle NULL filp->private_data correctly
Commit 13cfb7334e made cifs_ioctl use the tlink attached to the
cifsFileInfo for a filp. This ignores the case of an open directory
however, which in CIFS can have a NULL private_data until a readdir
is done on it.

This patch re-adds the NULL pointer checks that were removed in commit
50ae28f01 and moves the setting of tcon and "caps" variables lower.

Long term, a better fix would be to establish a f_op->open routine for
directories that populates that field at open time, but that requires
some other changes to how readdir calls are handled.

Reported-by: Kjell Rune Skaaraas <kjella79@yahoo.no>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-08 18:56:36 +00:00
Pavel Shilovsky c67236281c cifs: make cifs_set_oplock_level() take a cifsInodeInfo pointer
All the callers already have a pointer to struct cifsInodeInfo. Use it.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-05 17:39:01 +00:00
Jeff Layton d38922949d cifs: dereferencing first then checking
This patch is based on Dan's original patch. His original description is
below:

Smatch complained about a couple checking for NULL after dereferencing
bugs.  I'm not super familiar with the code so I did the conservative
thing and move the dereferences after the checks.

The dereferences in cifs_lock() and cifs_fsync() were added in
ba00ba64cf "cifs: make various routines use the cifsFileInfo->tcon
pointer".  The dereference in find_writable_file() was added in
6508d904e6 "cifs: have find_readable/writable_file filter by fsuid".
The comments there say it's possible to trigger the NULL dereference
under stress.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-04 19:39:07 +00:00
Suresh Jayaraman 6ef933a38a cifs: trivial comment fix: tlink_tree is now a rbtree
Noticed while reviewing (late) the rbtree conversion patchset (which has been merged
already).

Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-04 19:35:30 +00:00
Steve French 54eeafe1e4 [CIFS] Cleanup unused variable build warning
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 19:22:45 +00:00
Jeff Layton b647c35f77 cifs: convert tlink_tree to a rbtree
Radix trees are ideal when you want to track a bunch of pointers and
can't embed a tracking structure within the target of those pointers.
The tradeoff is an increase in memory, particularly if the tree is
sparse.

In CIFS, we use the tlink_tree to track tcon_link structs. A tcon_link
can never be in more than one tlink_tree, so there's no impediment to
using a rb_tree here instead of a radix tree.

Convert the new multiuser mount code to use a rb_tree instead. This
should reduce the memory required to manage the tlink_tree.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 19:20:23 +00:00
Jeff Layton 413e661c13 cifs: store pointer to master tlink in superblock (try #2)
This is the second version of this patch, the only difference between
it and the first one is that this explicitly makes cifs_sb_master_tlink
a static inline.

Instead of keeping a tag on the master tlink in the tree, just keep a
pointer to the master in the superblock. That eliminates the need for
using the radix tree to look up a tagged entry.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 19:15:09 +00:00
J. Bruce Fields df098db12a cifs: trivial doc fix: note setlease implemented
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 18:48:14 +00:00
Pavel Shilovsky e66673e39a CIFS: Add cifs_set_oplock_level
Simplify many places when we need to set oplock level on an inode.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 18:40:54 +00:00
Jiri Slaby 50ae28f014 FS: cifs, remove unneeded NULL tests
Stanse found that pSMBFile in cifs_ioctl and file->f_path.dentry in
cifs_user_write are dereferenced prior their test to NULL.

The alternative is not to dereference them before the tests. The patch is
to point out the problem, you have to decide.

While at it we cache the inode in cifs_user_write to a local variable
and use all over the function.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-02 03:47:21 +00:00
Christoph Hellwig 51ee4b84f5 locks: let the caller free file_lock on ->setlease failure
The caller allocated it, the caller should free it.

The only issue so far is that we could change the flp pointer even on an
error return if the fl_change callback failed.  But we can simply move
the flp assignment after the fl_change invocation, as the callers don't
care about the flp return value if the setlease call failed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-31 06:35:15 -07:00
J. Bruce Fields 05fa3135fd locks: fix setlease methods to free passed-in lock
We modified setlease to require the caller to allocate the new lease in
the case of creating a new lease, but forgot to fix up the filesystem
methods.

Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-30 18:08:15 -07:00
Linus Torvalds b4020c1b19 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:
  cifs: Cleanup and thus reduce smb session structure and fields used during authentication
  NTLM auth and sign - Use appropriate server challenge
  cifs: add kfree() on error path
  NTLM auth and sign - minor error corrections and cleanup
  NTLM auth and sign - Use kernel crypto apis to calculate hashes and smb signatures
  NTLM auth and sign - Define crypto hash functions and create and send keys needed for key exchange
  cifs: cifs_convert_address() returns zero on error
  NTLM auth and sign - Allocate session key/client response dynamically
  cifs: update comments - [s/GlobalSMBSesLock/cifs_file_list_lock/g]
  cifs: eliminate cifsInodeInfo->write_behind_rc (try #6)
  [CIFS] Fix checkpatch warnings and bump cifs version number
  cifs: wait for writeback to complete in cifs_flush
  cifs: convert cifsFileInfo->count to non-atomic counter
2010-10-29 10:37:27 -07:00
Al Viro d753ed9759 convert cifs
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:56 -04:00
Shirish Pargaonkar d3686d54c7 cifs: Cleanup and thus reduce smb session structure and fields used during authentication
Removed following fields from smb session structure
 cryptkey, ntlmv2_hash, tilen, tiblob
and ntlmssp_auth structure is allocated dynamically only if the auth mech
in NTLMSSP.

response field within a session_key structure is used to initially store the
target info (either plucked from type 2 challenge packet in case of NTLMSSP
or fabricated in case of NTLMv2 without extended security) and then to store
Message Authentication Key (mak) (session key + client response).

Server challenge or cryptkey needed during a NTLMSSP authentication
is now part of ntlmssp_auth structure which gets allocated and freed
once authenticaiton process is done.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:33 +00:00
Shirish Pargaonkar d3ba50b17a NTLM auth and sign - Use appropriate server challenge
Need to have cryptkey or server challenge in smb connection
(struct TCP_Server_Info) for ntlm and ntlmv2 auth types for which
cryptkey (Encryption Key) is supplied just once in Negotiate Protocol
response during an smb connection setup for all the smb sessions over
that smb connection.

For ntlmssp, cryptkey or server challenge is provided for every
smb session in type 2 packet of ntlmssp negotiation, the cryptkey
provided during Negotiation Protocol response before smb connection
does not count.

Rename cryptKey to cryptkey and related changes.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-29 01:47:30 +00:00
Dan Carpenter 6b03590412 cifs: add kfree() on error path
We leak 256 bytes here on this error path.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-28 00:55:45 +00:00
Shirish Pargaonkar f7c5445a9d NTLM auth and sign - minor error corrections and cleanup
Minor cleanup - Fix spelling mistake, make meaningful (goto) label

In function setup_ntlmv2_rsp(), do not return 0 and leak memory,
let the tiblob get freed.

For function find_domain_name(), pass already available nls table pointer
instead of loading and unloading the table again in this function.

For ntlmv2, the case sensitive password length is the length of the
response, so subtract session key length (16 bytes) from the .len.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-27 02:04:30 +00:00
Wu Fengguang 1b430beee5 writeback: remove nonblocking/encountered_congestion references
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks).  There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.

The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion.  The latter will lead to more seeky IO.

The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.

We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
   that would skip some dirty inodes on congestion and page out others, which
   is unfair in terms of LRU age.

Inspired by Christoph Hellwig. Thanks!

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:05 -07:00
Shirish Pargaonkar 307fbd31b6 NTLM auth and sign - Use kernel crypto apis to calculate hashes and smb signatures
Use kernel crypto sync hash apis insetead of cifs crypto functions.
The calls typically corrospond one to one except that insead of
key init, setkey is used.

Use crypto apis to generate smb signagtures also.
Use hmac-md5 to genereate ntlmv2 hash, ntlmv2 response, and HMAC (CR1 of
ntlmv2 auth blob.
User crypto apis to genereate signature and to verify signature.
md5 hash is used to calculate signature.
Use secondary key to calculate signature in case of ntlmssp.

For ntlmv2 within ntlmssp, during signature calculation, only 16 bytes key
(a nonce) stored within session key is used. during smb signature calculation.
For ntlm and ntlmv2 without extended security, 16 bytes key
as well as entire response (24 bytes in case of ntlm and variable length
in case of ntlmv2) is used for smb signature calculation.
For kerberos, there is no distinction between key and response.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:38:06 +00:00
Shirish Pargaonkar d2b915210b NTLM auth and sign - Define crypto hash functions and create and send keys needed for key exchange
Mark dependency on crypto modules in Kconfig.

Defining per structures sdesc and cifs_secmech which are used to store
crypto hash functions and contexts.  They are stored per smb connection
and used for all auth mechs to genereate hash values and signatures.

Allocate crypto hashing functions, security descriptiors, and respective
contexts when a smb/tcp connection is established.
Release them when a tcp/smb connection is taken down.

md5 and hmac-md5 are two crypto hashing functions that are used
throught the life of an smb/tcp connection by various functions that
calcualte signagure and ntlmv2 hash, HMAC etc.

structure ntlmssp_auth is defined as per smb connection.

ntlmssp_auth holds ciphertext which is genereated by rc4/arc4 encryption of
secondary key, a nonce using ntlmv2 session key and sent in the session key
field of the type 3 message sent by the client during ntlmssp
negotiation/exchange

A key is exchanged with the server if client indicates so in flags in
type 1 messsage and server agrees in flag in type 2 message of ntlmssp
negotiation.  If both client and agree, a key sent by client in
type 3 message of ntlmssp negotiation in the session key field.
The key is a ciphertext generated off of secondary key, a nonce, using
ntlmv2 hash via rc4/arc4.

Signing works for ntlmssp in this patch. The sequence number within
the server structure needs to be zero until session is established
i.e. till type 3 packet of ntlmssp exchange of a to be very first
smb session on that smb connection is sent.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:35:31 +00:00
Dan Carpenter b235f371a2 cifs: cifs_convert_address() returns zero on error
The cifs_convert_address() returns zero on error but this caller is
testing for negative returns.

Btw. "i" is unsigned here, so it's never negative.

Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:22:38 +00:00
Shirish Pargaonkar 21e733930b NTLM auth and sign - Allocate session key/client response dynamically
Start calculating auth response within a session.  Move/Add pertinet
data structures like session key, server challenge and ntlmv2_hash in
a session structure.  We should do the calculations within a session
before copying session key and response over to server data
structures because a session setup can fail.

Only after a very first smb session succeeds, it copy/make its
session key, session key of smb connection.  This key stays with
the smb connection throughout its life.
sequence_number within server is set to 0x2.

The authentication Message Authentication Key (mak) which consists
of session key followed by client response within structure session_key
is now dynamic.  Every authentication type allocates the key + response
sized memory within its session structure and later either assigns or
frees it once the client response is sent and if session's session key
becomes connetion's session key.

ntlm/ntlmi authentication functions are rearranged.  A function
named setup_ntlm_resp(), similar to setup_ntlmv2_resp(), replaces
function cifs_calculate_session_key().

size of CIFS_SESS_KEY_SIZE is changed to 16, to reflect the byte size
of the key it holds.

Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-26 18:20:10 +00:00
Suresh Jayaraman 6573e9b73e cifs: update comments - [s/GlobalSMBSesLock/cifs_file_list_lock/g]
GlobalSMBSesLock is now cifs_file_list_lock. Update comments to reflect this.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:01 +00:00
Jeff Layton eb4b756b1e cifs: eliminate cifsInodeInfo->write_behind_rc (try #6)
write_behind_rc is redundant and just adds complexity to the code. What
we really want to do instead is to use mapping_set_error to reset the
flags on the mapping when we find a writeback error and can't report it
to userspace yet.

For cifs_flush and cifs_fsync, we shouldn't reset the flags since errors
returned there do get reported to userspace.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:00 +00:00
Steve French 6c0f6218ba [CIFS] Fix checkpatch warnings and bump cifs version number
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:19:00 +00:00
Jeff Layton d3f1322af8 cifs: wait for writeback to complete in cifs_flush
The f_op->flush operation is the last chance to return a writeback
related error when closing a file. Ensure that we don't miss reporting
any errors by waiting for writeback to complete in cifs_flush before
proceeding.

There's no reason to do this when the file isn't open for write
however.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: David Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:18:59 +00:00
Jeff Layton 5f6dbc9e4a cifs: convert cifsFileInfo->count to non-atomic counter
The count for cifsFileInfo is currently an atomic, but that just adds
complexity for little value. We generally need to hold cifs_file_list_lock
to traverse the lists anyway so we might as well make this counter
non-atomic and simply use the cifs_file_list_lock to protect it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-25 00:18:59 +00:00