In fs/cifs/cifssmb.c, pLockData is tested for being NULL at the beginning
of the function, and not reassigned subsequently.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The paths in a DFS request are supposed to only have a single preceding
backslash, but we are sending them with a double backslash. This is
exposing a bug in Windows where it also sends a path in the response
that has a double backslash.

The existing code that builds the mount option string however expects a
double backslash prefix in a couple of places when it tries to use the
path returned by build_path_from_dentry. Fix compose_mount_options to
expect properly formed DFS paths (single backslash at front).

Also clean up error handling in that function. There was a possible
NULL pointer dereference and situations where a partially built option
string would be returned.

Tested against Samba 3.0.28-ish server and Samba 3.3 and Win2k8.

CC: Stable <stable@kernel.org>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Remove an already-checked error condition in SendReceiveBlockingLock
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Streamline SendReceiveBlockingLock: Use "goto out:" in an error condition
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Streamline SendReceiveBlockingLock: Use "goto out:" in an error condition
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Slightly streamline SendReceive[2]

Remove an else branch by naming the error condition what it is
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Check the return value of cifs_sign_smb[2]
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This avoids an unnecessary else branch
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This is no functional change, because in the "if" branch we do an early
"return 0;".
Signed-off-by: NVolker Lendecke <vl@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Simplify allocate_mid() slightly: Remove some unnecessary "else" branches
Signed-off-by: NVolker Lendecke <vl@samba.org>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

inbuf->smb_buf_length does not change in in wait_for_free_request() or in
allocate_mid(), so we can check it early.
Signed-off-by: NVolker Lendecke <vl@samba.org>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifs: store password in tcon

Each tcon has its own password for share-level security. Store it in
the tcon and wipe it clean and free it when freeing the tcon. When
doing the tree connect with share-level security, use the tcon password
instead of the session password.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifs: have calc_lanman_hash take more granular args

We need to use this routine to encrypt passwords associated with the
tcon too. Don't assume that the password will be attached to the
smb_session.

Also, make some of the values in the lower encryption functions
const since they aren't changed.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifs: zero out session password before freeing it

...just to be on the safe side.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifs: fix wait_for_response to time out sleeping processes correctly

The current scheme that CIFS uses to sleep and wait for a response is
not quite what we want. After sending a request, wait_for_response puts
the task to sleep with wait_event(). One of the conditions for
wait_event is a timeout (using time_after()).

The problem with this is that there is no guarantee that the process
will ever be woken back up. If the server stops sending data, then
cifs_demultiplex_thread will leave its response queue sleeping.

I think the only thing that saves us here is the fact that
cifs_dnotify_thread periodically (every 15s) wakes up sleeping processes
on all response_q's that have calls in flight.  This makes for
unnecessary wakeups of some processes. It also means large variability
in the timeouts since they're all woken up at once.

Instead of this, put the tasks to sleep with wait_event_timeout. This
makes them wake up on their own if they time out. With this change,
cifs_dnotify_thread should no longer be needed.

I've been testing this in conjunction with some other patches that I'm
working on. It doesn't seem to affect performance at all with with heavy
I/O. Identical iozone -ac runs complete in almost exactly the same time
(<1% difference in times).

Thanks to Wasrshi Nimara for initially pointing this out. Wasrshi, it
would be nice to know whether this patch also helps your testcase.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Cc: Wasrshi Nimara <warshinimara@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Windows allows you to deny access to the top of a share, but permit access to
a directory lower in the path.  With the prefixpath feature of cifs
(ie mounting \\server\share\directory\subdirectory\etc.) this should have
worked if the user specified a prefixpath which put the root of the mount
at a directory to which he had access, but we still were doing a lookup
on the root of the share (null path) when we should have been doing it on
the prefixpath subdirectory.

This fixes Samba bug # 5925
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Some applications/subsystems require mandatory byte range locks
(as is used for Windows/DOS/OS2 etc). Sending advisory (posix style)
byte range lock requests (instead of mandatory byte range locks) can
lead to problems for these applications (which expect that other
clients be prevented from writing to portions of the file which
they have locked and are updating).  This mount option allows
mounting cifs with the new mount option "forcemand" (or
"forcemandatorylock") in order to have the cifs client use mandatory
byte range locks (ie SMB/CIFS/Windows/NTFS style locks) rather than
posix byte range lock requests, even if the server would support
posix byte range lock requests.  This has no effect if the server
does not support the CIFS Unix Extensions (since posix style locks
require support for the CIFS Unix Extensions), but for mounts
to Samba servers this can be helpful for Wine and applications
that require mandatory byte range locks.
Acked-by: NJeff Layton <jlayton@redhat.com>
CC: Alexander Bokovoy <ab@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

In order to unify the smb_send routines, we need to reorganize the
routines that connect the sockets. Have ipv4_connect take a
TCP_Server_Info pointer and get the necessary fields from that.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

struct smb_vol is fairly large, it's probably best to kzalloc it...
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Clean up cifs_mount a bit by moving the code that creates new TCP
sessions into a separate function. Have that function search for an
existing socket and then create a new one if one isn't found.

Also reorganize the initializion of TCP_Server_Info a bit to prepare
for cleanup of the socket connection code.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The current code for setting the session serverName is IPv4-specific.
Allow it to be an IPv6 address as well. Use NIP* macros to set the
format.

This also entails increasing the length of the serverName field, so
declare a new macro for RFC1001 name length and use it in the
appropriate places.

Finally, drop the unicode_server_Name field from TCP_Server_Info since
it's not used. We can add it back later if needed, but for now it just
wastes memory.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Now that tasks sleeping in wait_for_response will time out on their own,
we're not reliant on the dnotify thread to do this. Mark it as
experimental code for now.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Mutexes are preferred for single-holder semaphores...
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

cifsd can outlive the last cifs mount. We need to hold a module
reference until it exits to prevent someone from unplugging
the module until we're ready.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Have cifs_show_options display the addr and prefixpath options in
/proc/mounts. Reduce struct dereferencing by adding some local
variables.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

While testing a kernel with memory poisoning enabled, I saw some warnings
about the redzone getting clobbered when chasing DFS referrals. The
buffer allocation for the unicode converted version of the searchName is
too small and needs to take null termination into account.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NSteve French <sfrench@us.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The conversion to write_begin/write_end interfaces had a bug where we
were passing a bad parameter to cifs_readpage_worker. Rather than
passing the page offset of the start of the write, we needed to pass the
offset of the beginning of the page. This was reliably showing up as
data corruption in the fsx-linux test from LTP.

It also became evident that this code was occasionally doing unnecessary
read calls. Optimize those away by using the PG_checked flag to indicate
that the unwritten part of the page has been initialized.

CC: Nick Piggin <npiggin@suse.de>
Acked-by: NDave Kleikamp <shaggy@us.ibm.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

If a connection with open file handles has gone down
and come back up and reconnected without reopening
the file handle yet, do not attempt to send an SMB close
request for this handle in cifs_close.  We were
checking for the connection being invalid in cifs_close
but since the connection may have been reconnected
we also need to check whether the file handle
was marked invalid (otherwise we could close the
wrong file handle by accident).
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

This was recently changed to check for need_reconnect, but should
actually be a check for a tidStatus of CifsExiting.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Fixes a data corruption under heavy stress in which pages could be left
dirty after all open instances of a inode have been closed.

In order to write contiguous pages whenever possible, cifs_writepages()
asks pagevec_lookup_tag() for more pages than it may write at one time.
Normally, it then resets index just past the last page written before calling
pagevec_lookup_tag() again.

If cifs_writepages() can't write the first page returned, it wasn't resetting
index, and the next call to pagevec_lookup_tag() resulted in skipping all of
the pages it previously returned, even though cifs_writepages() did nothing
with them.  This can result in data loss when the file descriptor is about
to be closed.

This patch ensures that index gets set back to the next returned page so
that none get skipped.
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: NJeff Layton <jlayton@redhat.com>
Cc: Shirish S Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Since these hit the same routines, and are relatively small, it is easier to review
them as one patch.

Fixed incorrect handling of the last option in some cases
Fixed prefixpath handling convert path_consumed into host depended string length (in bytes)
Use non default separator if it is provided in the original mount options
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NIgor Mammedov <niallain@gmail.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

set tcon->ses earlier

If the inital tree connect fails, we'll end up calling cifs_put_smb_ses
with a NULL pointer. Fix it by setting the tcon->ses earlier.
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Use a similar approach to the SMB session sharing. Add a list of tcons
attached to each SMB session. Move the refcount to non-atomic. Protect
all of the above with the cifs_tcp_ses_lock. Add functions to
properly find and put references to the tcons.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>