Commit Graph

700 Commits

Author SHA1 Message Date
Jeff Layton
ae6884a9da cifs: fix renaming one hardlink on top of another
cifs: fix renaming one hardlink on top of another

POSIX says that renaming one hardlink on top of another to the same
inode is a no-op. We had the logic mostly right, but forgot to clear
the return code.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-11-03 18:31:05 +00:00
Steve French
61de800d33 [CIFS] fix error in smb_send2
smb_send2 exit logic was strange, and with the previous change
could cause us to fail large
smb writes when all of the smb was not sent as one chunk.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-30 20:15:22 +00:00
Steve French
edf1ae4038 [CIFS] Reduce number of socket retries in large write path
CIFS in some heavy stress conditions cifs could get EAGAIN
repeatedly in smb_send2 which led to repeated retries and eventually
failure of large writes which could lead to data corruption.

There are three changes that were suggested by various network
developers:

1) convert cifs from non-blocking to blocking tcp sendmsg
(we left in the retry on failure)
2) change cifs to not set sendbuf and rcvbuf size for the socket
(let tcp autotune the buffer sizes since that works much better
in the TCP stack now)
3) if we have a partial frame sent in smb_send2, mark the tcp
session as invalid (close the socket and reconnect) so we do
not corrupt the remaining part of the SMB with the beginning
of the next SMB.

This does not appear to hurt performance measurably and has
been run in various scenarios, but it definately removes
a corruption that we were seeing in some high stress
test cases.

Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-29 00:47:57 +00:00
Linus Torvalds
db563fc2e8 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: handle the TCP_Server_Info->tsk field more carefully
  cifs: fix unlinking of rename target when server doesn't support open file renames
  [CIFS] improve setlease handling
  [CIFS] fix saving of resume key before CIFSFindNext
  cifs: make cifs_rename handle -EACCES errors
  [CIFS] fix build error
  [CIFS] undo changes in cifs_rename_pending_delete if it errors out
  cifs: track DeletePending flag in cifsInodeInfo
  cifs: don't use CREATE_DELETE_ON_CLOSE in cifs_rename_pending_delete
  [CIFS] eliminate usage of kthread_stop for cifsd
  [CIFS] Add nodfs mount option
2008-10-23 10:43:36 -07:00
Miklos Szeredi
f696a3659f [PATCH] move executable checking into ->permission()
For execute permission on a regular files we need to check if file has
any execute bits at all, regardless of capabilites.

This check is normally performed by generic_permission() but was also
added to the case when the filesystem defines its own ->permission()
method.  In the latter case the filesystem should be responsible for
performing this check.

Move the check from inode_permission() inside filesystems which are
not calling generic_permission().

Create a helper function execute_ok() that returns true if the inode
is a directory or if any execute bits are present in i_mode.

Also fix up the following code:

 - coda control file is never executable
 - sysctl files are never executable
 - hfs_permission seems broken on MAY_EXEC, remove
 - hfsplus_permission is eqivalent to generic_permission(), remove

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-10-23 05:13:25 -04:00
Christoph Hellwig
3222a3e55f [PATCH] fix ->llseek for more directories
With this patch all directory fops instances that have a readdir
that doesn't take the BKL are switched to generic_file_llseek.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2008-10-23 05:13:21 -04:00
Jeff Layton
b1c8d2b421 cifs: handle the TCP_Server_Info->tsk field more carefully
cifs: handle the TCP_Server_Info->tsk field more carefully

We currently handle the TCP_Server_Info->tsk field without any locking,
but with some half-measures to try and prevent races. These aren't
really sufficient though. When taking down cifsd, use xchg() to swap
the contents of the tsk field with NULL so we don't end up trying
to send it more than one signal. Also, don't allow cifsd to exit until
the signal is received if we expect one.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-23 05:06:20 +00:00
Jeff Layton
8d281efb67 cifs: fix unlinking of rename target when server doesn't support open file renames
cifs: fix unlinking of rename target when server doesn't support open file renames

The patch to make cifs_rename undoable broke renaming one file on top of
another when the server doesn't support busy file renames. Remove the
code that uses busy file renames to unlink the target file, and just
have it call cifs_unlink. If the rename of the source file fails, then
the unlink won't be undoable, but hopefully that's rare enough that it
won't be a problem.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-23 04:50:17 +00:00
Steve French
84210e9120 [CIFS] improve setlease handling
fcntl(F_SETLEASE) currently is not exported by cifs (nor by local file
systems) so cifs grants leases based on how other local processes have
opened the file not by whether the file is cacheable (oplocked).  This
adds the check to make sure that the file is cacheable on the client
before checking whether we can grant the lease locally
(generic_setlease).  It also adds a mount option for cifs (locallease)
if the user wants to override this and try to grant leases even
if the server did not grant oplock.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-23 04:42:37 +00:00
Jeff Layton
a364bc0b37 [CIFS] fix saving of resume key before CIFSFindNext
We recently fixed the cifs readdir code so that it saves the resume key
before calling CIFSFindNext. Unfortunately, this assumes that we have
just done a CIFSFindFirst (or FindNext) and have resume info to save.
This isn't necessarily the case. Fix the code to save resume info if we
had to reinitiate the search, and after a FindNext.

This fixes connectathon basic test6 against NetApp filers.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
CC: Stable <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-21 14:42:13 +00:00
Jeff Layton
14121bdccc cifs: make cifs_rename handle -EACCES errors
cifs: make cifs_rename handle -EACCES errors

Some servers seem to return -EACCES when attempting to rename one
open file on top of another. Refactor the cifs_rename logic to
attempt to rename the target file out of the way in this situation.

This also fixes the "unlink_target" logic to be undoable if the
subsequent rename fails.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-20 18:44:13 +00:00
Steve French
413460980e [CIFS] fix build error
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-20 18:24:42 +00:00
Alexey Dobriyan
bb26b963d8 fs/Kconfig: move CIFS out
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:42 -07:00
Rik van Riel
4f98a2fee8 vmscan: split LRU lists into anon & file sets
Split the LRU lists in two, one set for pages that are backed by real file
systems ("file") and one for pages that are backed by memory and swap
("anon").  The latter includes tmpfs.

The advantage of doing this is that the VM will not have to scan over lots
of anonymous pages (which we generally do not want to swap out), just to
find the page cache pages that it should evict.

This patch has the infrastructure and a basic policy to balance how much
we scan the anon lists and how much we scan the file lists.  The big
policy changes are in separate patches.

[lee.schermerhorn@hp.com: collect lru meminfo statistics from correct offset]
[kosaki.motohiro@jp.fujitsu.com: prevent incorrect oom under split_lru]
[kosaki.motohiro@jp.fujitsu.com: fix pagevec_move_tail() doesn't treat unevictable page]
[hugh@veritas.com: memcg swapbacked pages active]
[hugh@veritas.com: splitlru: BDI_CAP_SWAP_BACKED]
[akpm@linux-foundation.org: fix /proc/vmstat units]
[nishimura@mxp.nes.nec.co.jp: memcg: fix handling of shmem migration]
[kosaki.motohiro@jp.fujitsu.com: adjust Quicklists field of /proc/meminfo]
[kosaki.motohiro@jp.fujitsu.com: fix style issue of get_scan_ratio()]
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:50:25 -07:00
Steve French
3270958b71 [CIFS] undo changes in cifs_rename_pending_delete if it errors out
The cifs_rename_pending_delete process involves multiple steps. If it
fails and we're going to return error, we don't want to leave things in
a half-finished state. Add code to the function to undo changes if
a call fails.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-20 00:44:19 +00:00
Jeff Layton
9a8165fce7 cifs: track DeletePending flag in cifsInodeInfo
cifs: track DeletePending flag in cifsInodeInfo

The QPathInfo call returns a flag that indicates whether DELETE_ON_CLOSE
is set. Track it in the cifsInodeInfo.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-20 00:33:52 +00:00
Jeff Layton
dd1db2dedc cifs: don't use CREATE_DELETE_ON_CLOSE in cifs_rename_pending_delete
cifs: don't use CREATE_DELETE_ON_CLOSE in cifs_rename_pending_delete

CREATE_DELETE_ON_CLOSE apparently has different semantics than when you
set the DELETE_ON_CLOSE bit after opening the file. Setting it in the
open says "delete this file as soon as this filehandle is closed". That's
not what we want for cifs_rename_pending_delete.

Don't set this bit in the CreateFlags. Experimentation shows that
setting this flag in the SET_FILE_INFO call has no effect.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-17 14:47:13 +00:00
Jeff Layton
469ee614aa [CIFS] eliminate usage of kthread_stop for cifsd
When cifs_demultiplex_thread was converted to a kthread based kernel
thread, great pains were taken to make it so that kthread_stop would be
used to bring it down. This just added unnecessary complexity since we
needed to use a signal anyway to break out of kernel_recvmsg.

Also, cifs_demultiplex_thread does a bit of cleanup as it's exiting, and
we need to be certain that this gets done. It's possible for a kthread
to exit before its main function is ever run if kthread_stop is called
soon after its creation. While I'm not sure that this is a real problem
with cifsd now, it could be at some point in the future if cifs_mount is
ever changed to bring down the thread quickly.

The upshot here is that using kthread_stop to bring down the thread just
adds extra complexity with no real benefit. This patch changes the code
to use the original method to bring down the thread, but still leaves it
so that the thread is actually started with kthread_run.

This seems to fix the deadlock caused by the reproducer in this bug
report:

https://bugzilla.samba.org/show_bug.cgi?id=5720

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-16 18:46:39 +00:00
Steve French
2c1b861539 [CIFS] Add nodfs mount option
Older samba server (eg. 3.0.24 from Debian etch) don't work correctly,
if DFS paths are used. Such server claim that they support DFS, but fail
to process some requests with DFS paths. Starting with Linux 2.6.26,
the cifs clients starts sending DFS paths in such situations, rendering
it unuseable with older samba servers.

The nodfs mount options forces a share to be used with non DFS paths,
even if the server claims, that it supports it.

Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Acked-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-16 18:35:21 +00:00
Jeff Layton
14835a3325 [CIFS] cifs: remove pointless lock and unlock of GlobalMid_Lock in header_assemble
We lock GlobalMid_Lock in header_assemble and then immediately unlock it
again without doing anything. Not sure what this was intended to do, but
remove it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-12 13:34:11 +00:00
Steve French
b77d753c41 [CIFS] Check that last search entry resume key is valid
Jeff's recent patch to add a last_entry field in the search structure
to better construct resume keys did not validate that the server
sent us a plausible pointer to the last entry.  This adds that.

Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-08 19:13:46 +00:00
Steve French
0752f1522a [CIFS] make sure we have the right resume info before calling CIFSFindNext
When we do a seekdir() or equivalent, we usually end up doing a
FindFirst call and then call FindNext until we get to the offset that we
want. The problem is that when we call FindNext, the code usually
doesn't have the proper info (mostly, the filename of the entry from the
last search) to resume the search.

Add a "last_entry" field to the cifs_search_info that points to the last
entry in the search. We calculate this pointer by using the
LastNameOffset field from the search parms that are returned. We then
use that info to do a cifs_save_resume_key before we call CIFSFindNext.

This patch allows CIFS to reliably pass the "telldir" connectathon test.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
CC: Stable <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-07 20:03:33 +00:00
Steve French
6050247d80 [CIFS] clean up error handling in cifs_unlink
Currently, if a standard delete fails and we end up getting -EACCES
we try to clear ATTR_READONLY and try the delete again. If that
then fails with -ETXTBSY then we try a rename_pending_delete. We
aren't handling other errors appropriately though.

Another client could have deleted the file in the meantime and
we get back -ENOENT, for instance. In that case we wouldn't do a
d_drop. Instead of retrying in a separate call, simply goto the
original call and use the error handling from that.

Also, we weren't properly undoing any attribute changes that
were done before returning an error back to the caller.

CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-07 18:42:52 +00:00
Jeff Layton
6b37faa175 [CIFS] fix some settings of cifsAttrs after calling SetFileInfo and SetPathInfo
We only need to set them when we call SetFileInfo or SetPathInfo
directly, and as soon as possible after then. We had one place setting
it where it didn't need to be, and another place where it was missing.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-10-06 21:54:41 +00:00
Jeff Layton
dfd15c46a6 cifs: explicitly revoke SPNEGO key after session setup
cifs: explicitly revoke SPNEGO key after session setup

The SPNEGO blob returned by an upcall can only be used once. Explicitly
revoke it to make sure that we never pick it up again after session
setup exits.

This doesn't seem to be that big an issue on more recent kernels, but
older kernels seem to link keys into the session keyring by default.
That said, explicitly revoking the key seems like a reasonable thing
to do here.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 20:59:37 +00:00
Nick Piggin
d9414774dc cifs: Convert cifs to new aops.
cifs: Convert cifs to new aops.

This patch is based on the one originally posted by Nick Piggin. His
patch was very close, but had a couple of small bugs. Nick's original
comments follow:

This is another relatively naive conversion. Always do the read upfront
when the page is not uptodate (unless we're in the writethrough path).

Fix an uninitialized data exposure where SetPageUptodate was called
before the page was uptodate.

SetPageUptodate and switch to writeback mode in the case that the full
page was dirtied.

Acked-by: Shaggy <shaggy@austin.ibm.com>
Acked-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 19:32:56 +00:00
Steve French
d388908ec4 [CIFS] update DOS attributes in cifsInode if we successfully changed them
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 19:22:52 +00:00
Jeff Layton
391e575556 cifs: remove NULL termination from rename target in CIFSSMBRenameOpenFIle
cifs: remove NULL termination from rename target in CIFSSMBRenameOpenFIle

The rename destination isn't supposed to be null terminated. Also,
change the name string arg to be const.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 19:07:36 +00:00
Jeff Layton
7ce86d5a93 cifs: work around samba returning -ENOENT on SetFileDisposition call
cifs: work around samba returning -ENOENT on SetFileDisposition call

Samba seems to return STATUS_OBJECT_NAME_NOT_FOUND when we try to set
the delete on close bit after doing a rename by filehandle. This looks
like a samba bug to me, but a lot of servers will do this. For now,
pretend an -ENOENT return is a success.

Samba does however seem to respect the CREATE_DELETE_ON_CLOSE bit
when opening files that already exist. Windows will ignore it, but
so adding it to the open flags should be harmless.

We're also currently ignoring the return code on the rename by
filehandle, so no need to set rc based on it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 18:59:20 +00:00
Jeff Layton
74553b1b6a cifs: fix inverted NULL check after kmalloc
cifs: fix inverted NULL check after kmalloc

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-24 18:55:11 +00:00
Steve French
9d81523480 [CIFS] clean up upcall handling for dns_resolver keys
We're given the datalen in the downcall, so there's no need to do any
calls to strlen(). Just keep track of the datalen in the key. Finally,
add a sanity check of the data in the downcall to make sure that it
looks like a real IP address.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 18:46:07 +00:00
Steve French
ee2fd967fb [CIFS] fix busy-file renames and refactor cifs_rename logic
Break out the code that does the actual renaming into a separate
function and have cifs_rename call that. That function will attempt a
path based rename first and then do a filehandle based one if it looks
like the source is busy.

The existing logic tried a path based rename first, but if we needed to
remove the destination then it only attempted a filehandle based rename
afterward. Not all servers support renaming by filehandle, so we need to
always attempt path rename first and fall back to filehandle rename if
it doesn't work.

This also fixes renames of open files on windows servers (at least when
the source and destination directories are the same).

CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 18:23:33 +00:00
Jeff Layton
6d22f09896 cifs: add function to set file disposition
cifs: add function to set file disposition

The proper way to set the delete on close bit on an already existing
file is to use SET_FILE_INFO with an infolevel of
SMB_FILE_DISPOSITION_INFO. Add a function to do that and have the
silly-rename code use it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 17:39:28 +00:00
Steve French
7c9c3760b3 [CIFS] add constants for string lengths of keynames in SPNEGO upcall string
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 17:23:09 +00:00
Jeff Layton
a12a1ac7a4 cifs: move rename and delete-on-close logic into helper function
cifs: move rename and delete-on-close logic into helper function

When a file is still open on the server, we attempt to set the
DELETE_ON_CLOSE bit and rename it to a new filename. When the
last opener closes the file, the server should delete it.

This patch moves this mechanism into a helper function and has
the two places in cifs_unlink that do this procedure call it. It
also fixes the open flags to be correct.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 17:11:03 +00:00
Jeff Layton
2846d38647 cifs: have find_writeable_file prefer filehandles opened by same task
When the CIFS client goes to write out pages, it needs to pick a
filehandle to write to. find_writeable_file however just picks the
first filehandle that it finds. This can cause problems when a lock
is issued against a particular filehandle and we pick a different
filehandle to write to.

This patch tries to avert this situation by having find_writable_file
prefer filehandles that have a pid that matches the current task.
This seems to fix lock test 11 from the connectathon test suite when
run against a windows server.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-23 02:24:13 +00:00
Pekka Enberg
232087cb73 cifs: don't use GFP_KERNEL with GFP_NOFS
GFP_KERNEL and GFP_NOFS are mutually exclusive. If you combine them, you end up
with plain GFP_KERNEL which can deadlock in cases where you really want
GFP_NOFS.

Cc: Steve French <sfrench@samba.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-22 22:23:56 +00:00
Steve French
388e57b275 [CIFS] use common code for turning off ATTR_READONLY in cifs_unlink
We already have a cifs_set_file_info function that can flip DOS
attribute bits. Have cifs_unlink call it to handle turning ATTR_HIDDEN
on and ATTR_READONLY off when an unlink attempt returns -EACCES.

This also removes a level of indentation from cifs_unlink.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-16 23:50:58 +00:00
Jeff Layton
5f0319a790 cifs: clean up variables in cifs_unlink
Change parameters to cifs_unlink to match the ones used in the generic
VFS. Add some local variables to cut down on the amount of struct
dereferencing that needs to be done, and eliminate some unneeded NULL
pointer checks on the parent directory inode. Finally, rename pTcon
to "tcon" to more closely match standard kernel coding style.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-09-16 20:14:34 +00:00
Steve French
c76da9da1f [CIFS] Turn off Unicode during session establishment for plaintext authentication
LANMAN session setup did not support Unicode (after session setup, unicode can
still be used though).

Fixes samba bug# 5319

CC: Jeff Layton <jlayton@redhat.com>
CC: Stable Kernel <stable@vger.kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-28 15:32:22 +00:00
Steve French
2e655021b8 [CIFS] update cifs change log
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-28 15:30:06 +00:00
Jeff Layton
838726c475 cifs: fix O_APPEND on directio mounts
The direct I/O write codepath for CIFS is done through
cifs_user_write(). That function does not currently call
generic_write_checks() so the file position isn't being properly set
when the file is opened with O_APPEND.  It's also not doing the other
"normal" checks that should be done for a write call.

The problem is currently that when you open a file with O_APPEND on a
mount with the directio mount option, the file position is set to the
beginning of the file. This makes any subsequent writes clobber the data
in the file starting at the beginning.

This seems to fix the problem in cursory testing. It is, however
important to note that NFS disallows the combination of
(O_DIRECT|O_APPEND). If my understanding is correct, the concern is
races with multiple clients appending to a file clobbering each others'
data. Since the write model for CIFS and NFS is pretty similar in this
regard, CIFS is probably subject to the same sort of races. What's
unclear to me is why this is a particular problem with O_DIRECT and not
with buffered writes...

Regardless, disallowing O_APPEND on an entire mount is probably not
reasonable, so we'll probably just have to deal with it and reevaluate
this flag combination when we get proper support for O_DIRECT. In the
meantime this patch at least fixes the existing problem.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-28 14:15:32 +00:00
Steve French
bcc55c6664 [CIFS] Fix plaintext authentication
The last eight bytes of the password field were not cleared when doing lanman plaintext password authentication. This patch fixes that.

I tested it with Samba by setting password
encryption to no in the server's smb.conf.  Other servers also can be
configured to force plaintext authentication.    Note that plaintexti
authentication requires setting /proc/fs/cifs/SecurityFlags to 0x30030
on the client (enabling both LANMAN and also plaintext password support).
Also note that LANMAN support (and thus plaintext password support) requires
CONFIG_CIFS_WEAK_PW_HASH to be enabled in menuconfig.

CC: Jeff Layton <jlayton@redhat.com>
CC: Stable Kernel <stable@vger.kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-27 21:30:22 +00:00
Jeff Layton
87ed1d65fb [CIFS] Add destroy routine for dns_resolver
Otherwise, we're leaking the payload memory.

CC: Stable Kernel <stable@vger.kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-27 21:17:41 +00:00
Steve French
6ce5eecb9c [CIFS] check version in spnego upcall response
Currently, we don't check the version in the SPNEGO upcall response
even though one is provided. Jeff and Q have made the corresponding
change to the Samba client (cifs.upcall).

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-26 00:37:14 +00:00
Steve French
3d2af3465e [CIFS] Kerberos support not considered experimental anymore
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-19 20:51:09 +00:00
Steve French
c16fefa563 [CIFS] distinguish between Kerberos and MSKerberos in upcall
Properly handle MSKRB5 by passing sec=mskrb5 to the upcall so that the
spengo blob can be generated appropriately. Also, make
decode_negTokenInit prefer whichever mechanism is first in the list.

Needed for some NetApp servers, and possibly some older
versions of Windows which treat the two KRB5 mechanisms differently.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-19 19:35:33 +00:00
Jeff Layton
cb7691b648 cifs: add local server pointer to cifs_setup_session
cifs_setup_session references pSesInfo->server several times. That
pointer shouldn't change during the life of the function so grab it
once and store it in a local var. This makes the code look a little
cleaner too.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-19 17:11:35 +00:00
Ilpo Järvinen
aab3a8c7a3 [CIFS] reindent misindented statement
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-19 14:23:37 +00:00
Steve French
ad661334b8 [CIFS] mount of IPC$ breaks with iget patch
In looking at network named pipe support on cifs, I noticed that
Dave Howell's iget patch:

    iget: stop CIFS from using iget() and read_inode()

broke mounts to IPC$ (the interprocess communication share), and don't
handle the error case (when getting info on the root inode fails).

Thanks to Gunter who noted a typo in a debug line in the original
version of this patch.

CC: David Howells <dhowells@redhat.com>
CC: Gunter Kukkukk <linux@kukkukk.com>
CC: Stable Kernel <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-08-14 03:55:14 +00:00