159 Commits

Author SHA1 Message Date
Shyam Prasad N
43d7093525 cifs: return errors during session setup during reconnects
commit 8ea21823aa584b55ba4b861307093b78054b0c1b upstream.

During reconnects, we check the return value from
cifs_negotiate_protocol, and have handlers for both success
and failures. But if that passes, and cifs_setup_session
returns any errors other than -EACCES, we do not handle
that. This fix adds a handler for that, so that we don't
go ahead and try a tree_connect on a failed session.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-14 16:52:41 +02:00
Steve French
91e7b49a44 smb3: warn on confusing error scenario with sec=krb5
commit 0a018944eee913962bce8ffebbb121960d5125d9 upstream.

When mounting with Kerberos, users have been confused about the
default error returned in scenarios in which either keyutils is
not installed or the user did not properly acquire a krb5 ticket.
Log a warning message in the case that "ENOKEY" is returned
from the get_spnego_key upcall so that users can better understand
why mount failed in those two cases.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 11:02:06 +02:00
Samuel Cabrero
79d25ee27b cifs: Check for timeout on Negotiate stage
[ Upstream commit 76e752701a8af4404bbd9c45723f7cbd6e4a251e ]

Some servers seem to accept connections while booting but never send
the SMBNegotiate response neither close the connection, causing all
processes accessing the share hang on uninterruptible sleep state.

This happens when the cifs_demultiplex_thread detects the server is
unresponsive so releases the socket and start trying to reconnect.
At some point, the faulty server will accept the socket and the TCP
status will be set to NeedNegotiate. The first issued command accessing
the share will start the negotiation (pid 5828 below), but the response
will never arrive so other commands will be blocked waiting on the mutex
(pid 55352).

This patch checks for unresponsive servers also on the negotiate stage
releasing the socket and reconnecting if the response is not received
and checking again the tcp state when the mutex is acquired.

PID: 55352  TASK: ffff880fd6cc02c0  CPU: 0   COMMAND: "ls"
 #0 [ffff880fd9add9f0] schedule at ffffffff81467eb9
 #1 [ffff880fd9addb38] __mutex_lock_slowpath at ffffffff81468fe0
 #2 [ffff880fd9addba8] mutex_lock at ffffffff81468b1a
 #3 [ffff880fd9addbc0] cifs_reconnect_tcon at ffffffffa042f905 [cifs]
 #4 [ffff880fd9addc60] smb_init at ffffffffa042faeb [cifs]
 #5 [ffff880fd9addca0] CIFSSMBQPathInfo at ffffffffa04360b5 [cifs]
 ....

Which is waiting a mutex owned by:

PID: 5828   TASK: ffff880fcc55e400  CPU: 0   COMMAND: "xxxx"
 #0 [ffff880fbfdc19b8] schedule at ffffffff81467eb9
 #1 [ffff880fbfdc1b00] wait_for_response at ffffffffa044f96d [cifs]
 #2 [ffff880fbfdc1b60] SendReceive at ffffffffa04505ce [cifs]
 #3 [ffff880fbfdc1bb0] CIFSSMBNegotiate at ffffffffa0438d79 [cifs]
 #4 [ffff880fbfdc1c50] cifs_negotiate_protocol at ffffffffa043b383 [cifs]
 #5 [ffff880fbfdc1c80] cifs_reconnect_tcon at ffffffffa042f911 [cifs]
 #6 [ffff880fbfdc1d20] smb_init at ffffffffa042faeb [cifs]
 #7 [ffff880fbfdc1d60] CIFSSMBQFSInfo at ffffffffa0434eb0 [cifs]
 ....

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurélien Aptel <aaptel@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:34 +02:00
Ronnie Sahlberg
f78ba732cd cifs: fail i/o on soft mounts if sessionsetup errors out
commit b0dd940e582b6a60296b9847a54012a4b080dc72 upstream.

RHBZ: 1579050

If we have a soft mount we should fail commands for session-setup
failures (such as the password having changed/ account being deleted/ ...)
and return an error back to the application.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:31:08 -05:00
Steve French
92225e4100 smb3: send CAP_DFS capability during session setup
commit 8d33096a460d5b9bd13300f01615df5bb454db10 upstream.

We had a report of a server which did not do a DFS referral
because the session setup Capabilities field was set to 0
(unlike negotiate protocol where we set CAP_DFS).  Better to
send it session setup in the capabilities as well (this also
more closely matches Windows client behavior).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-25 10:51:39 +02:00
Pavel Shilovsky
84bdf5e258 SMB3: Fix deadlock in validate negotiate hits reconnect
commit e99c63e4d86d3a94818693147b469fa70de6f945 upstream.

Currently we skip SMB2_TREE_CONNECT command when checking during
reconnect because Tree Connect happens when establishing
an SMB session. For SMB 3.0 protocol version the code also calls
validate negotiate which results in SMB2_IOCL command being sent
over the wire. This may deadlock on trying to acquire a mutex when
checking for reconnect. Fix this by skipping SMB2_IOCL command
when doing the reconnect check.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-25 10:51:38 +02:00
Pavel Shilovsky
9033b4f2bc CIFS: Do not count -ENODATA as failure for query directory
commit 8e6e72aeceaaed5aeeb1cb43d3085de7ceb14f79 upstream.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:33:28 +01:00
Dan Carpenter
fe6198c278 CIFS: fix wrapping bugs in num_entries()
commit 56446f218af1133c802dad8e9e116f07f381846c upstream.

The problem is that "entryptr + next_offset" and "entryptr + len + size"
can wrap.  I ended up changing the type of "entryptr" because it makes
the math easier when we don't have to do so much casting.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:36:37 +02:00
Steve French
7aed5a52b8 SMB3: Number of requests sent should be displayed for SMB3 not just CIFS
[ Upstream commit 289131e1f1e6ad8c661ec05e176b8f0915672059 ]

For SMB2/SMB3 the number of requests sent was not displayed
in /proc/fs/cifs/Stats unless CONFIG_CIFS_STATS2 was
enabled (only number of failed requests displayed). As
with earlier dialects, we should be displaying these
counters if CONFIG_CIFS_STATS is enabled. They
are important for debugging.

e.g. when you cat /proc/fs/cifs/Stats (before the patch)
Resources in use
CIFS Session: 1
Share (unique mount targets): 2
SMB Request/Response Buffer: 1 Pool size: 5
SMB Small Req/Resp Buffer: 1 Pool size: 30
Operations (MIDs): 0

0 session 0 share reconnects
Total vfs operations: 690 maximum at one time: 2

1) \\localhost\test
SMBs: 975
Negotiates: 0 sent 0 failed
SessionSetups: 0 sent 0 failed
Logoffs: 0 sent 0 failed
TreeConnects: 0 sent 0 failed
TreeDisconnects: 0 sent 0 failed
Creates: 0 sent 2 failed
Closes: 0 sent 0 failed
Flushes: 0 sent 0 failed
Reads: 0 sent 0 failed
Writes: 0 sent 0 failed
Locks: 0 sent 0 failed
IOCTLs: 0 sent 1 failed
Cancels: 0 sent 0 failed
Echos: 0 sent 0 failed
QueryDirectories: 0 sent 63 failed

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:43:00 +02:00
Paulo Alcantara
2c4f6b710b cifs: Fix infinite loop when using hard mount option
commit 7ffbe65578b44fafdef577a360eb0583929f7c6e upstream.

For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.

So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.

Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().

Here's an example of how to trigger that:

$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard

(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511

$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511  0.0  0.0  12892  1008 pts/0    S    12:24   0:00 stat -f
/mnt/test

$ kill -9 2511

(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511 83.2  0.0  12892  1008 pts/0    R    12:24  30:01 stat -f
/mnt/test

By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.

Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-11 16:26:43 +02:00
Steve French
a6c9a62e0f smb3: on reconnect set PreviousSessionId field
commit b2adf22fdfba85a6701c481faccdbbb3a418ccfc upstream.

The server detects reconnect by the (non-zero) value in PreviousSessionId
of SMB2/SMB3 SessionSetup request, but this behavior regressed due
to commit 166cea4dc3a4f66f020cfb9286225ecd228ab61d
("SMB2: Separate RawNTLMSSP authentication from SMB2_sess_setup")

CC: Stable <stable@vger.kernel.org>
CC: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-26 08:08:08 +08:00
Christophe JAILLET
cfea563e71 SMB2: Fix share type handling
[ Upstream commit cd1230070ae1c12fd34cf6a557bfa81bf9311009 ]

In fs/cifs/smb2pdu.h, we have:
#define SMB2_SHARE_TYPE_DISK    0x01
#define SMB2_SHARE_TYPE_PIPE    0x02
#define SMB2_SHARE_TYPE_PRINT   0x03

Knowing that, with the current code, the SMB2_SHARE_TYPE_PRINT case can
never trigger and printer share would be interpreted as disk share.

So, test the ShareType value for equality instead.

Fixes: faaf946a7d5b ("CIFS: Add tree connect/disconnect capability for SMB2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:47:55 +02:00
Pavel Shilovsky
df09b6f7b5 CIFS: Enable encryption during session setup phase
commit cabfb3680f78981d26c078a26e5c748531257ebb upstream.

In order to allow encryption on SMB connection we need to exchange
a session key and generate encryption and decryption keys.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:00:08 +01:00
Steve French
fca16f9a02 SMB3: Validate negotiate request must always be signed
commit 4587eee04e2ac7ac3ac9fa2bc164fb6e548f99cd upstream.

According to MS-SMB2 3.2.55 validate_negotiate request must
always be signed. Some Windows can fail the request if you send it unsigned

See kernel bugzilla bug 197311

CC: Stable <stable@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:00:08 +01:00
Daniel N Pettersson
f59eda1664 cifs: Fix autonegotiate security settings mismatch
commit 9aca7e454415f7878b28524e76bebe1170911a88 upstream.

Autonegotiation gives a security settings mismatch error if the SMB
server selects an SMBv3 dialect that isn't SMB3.02. The exact error is
"protocol revalidation - security settings mismatch".
This can be tested using Samba v4.2 or by setting the global Samba
setting max protocol = SMB3_00.

The check that fails in smb3_validate_negotiate is the dialect
verification of the negotiate info response. This is because it tries
to verify against the protocol_id in the global smbdefault_values. The
protocol_id in smbdefault_values is SMB3.02.
In SMB2_negotiate the protocol_id in smbdefault_values isn't updated,
it is global so it probably shouldn't be, but server->dialect is.

This patch changes the check in smb3_validate_negotiate to use
server->dialect instead of server->vals->protocol_id. The patch works
with autonegotiate and when using a specific version in the vers mount
option.

Signed-off-by: Daniel N Pettersson <danielnp@axis.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-17 13:21:12 +01:00
Steve French
0e1b85a41a SMB: Validate negotiate (to protect against downgrade) even if signing off
commit 0603c96f3af50e2f9299fa410c224ab1d465e0f9 upstream.

As long as signing is supported (ie not a guest user connection) and
connection is SMB3 or SMB3.02, then validate negotiate (protect
against man in the middle downgrade attacks).  We had been doing this
only when signing was required, not when signing was just enabled,
but this more closely matches recommended SMB3 behavior and is
better security.  Suggested by Metze.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Acked-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:44:01 +02:00
Steve French
df1be20664 SMB3: Warn user if trying to sign connection that authenticated as guest
commit c721c38957fb19982416f6be71aae7b30630d83b upstream.

It can be confusing if user ends up authenticated as guest but they
requested signing (server will return error validating signed packets)
so add log message for this.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:44:01 +02:00
Steve French
f2d395b7bd Fix SMB3.1.1 guest authentication to Samba
commit 23586b66d84ba3184b8820277f3fc42761640f87 upstream.

Samba rejects SMB3.1.1 dialect (vers=3.1.1) negotiate requests from
the kernel client due to the two byte pad at the end of the negotiate
contexts.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:44:01 +02:00
Sachin Prabhu
8b053290ee cifs: Fix df output for users with quota limits
commit 42bec214d8bd432be6d32a1acb0a9079ecd4d142 upstream.

The df for a SMB2 share triggers a GetInfo call for
FS_FULL_SIZE_INFORMATION. The values returned are used to populate
struct statfs.

The problem is that none of the information returned by the call
contains the total blocks available on the filesystem. Instead we use
the blocks available to the user ie. quota limitation when filling out
statfs.f_blocks. The information returned does contain Actual free units
on the filesystem and is used to populate statfs.f_bfree. For users with
quota enabled, it can lead to situations where the total free space
reported is more than the total blocks on the system ending up with df
reports like the following

 # df -h /mnt/a
Filesystem         Size  Used Avail Use% Mounted on
//192.168.22.10/a  2.5G -2.3G  2.5G    - /mnt/a

To fix this problem, we instead populate both statfs.f_bfree with the
same value as statfs.f_bavail ie. CallerAvailableAllocationUnits. This
is similar to what is done already in the code for cifs and df now
reports the quota information for the user used to mount the share.

 # df --si /mnt/a
Filesystem         Size  Used Avail Use% Mounted on
//192.168.22.10/a  2.7G  101M  2.6G   4% /mnt/a

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pierguido Lambri <plambri@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30 10:21:49 +02:00
Steve French
8dd4e3ff1b SMB3: Work around mount failure when using SMB3 dialect to Macs
commit 7db0a6efdc3e990cdfd4b24820d010e9eb7890ad upstream.

Macs send the maximum buffer size in response on ioctl to validate
negotiate security information, which causes us to fail the mount
as the response buffer is larger than the expected response.

Changed ioctl response processing to allow for padding of validate
negotiate ioctl response and limit the maximum response size to
maximum buffer size.

Signed-off-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:28:40 +02:00
Germano Percossi
f79ef57911 CIFS: remove bad_network_name flag
commit a0918f1ce6a43ac980b42b300ec443c154970979 upstream.

STATUS_BAD_NETWORK_NAME can be received during node failover,
causing the flag to be set and making the reconnect thread
always unsuccessful, thereafter.

Once the only place where it is set is removed, the remaining
bits are rendered moot.

Removing it does not prevent "mount" from failing when a non
existent share is passed.

What happens when the share really ceases to exist while the
share is mounted is undefined now as much as it was before.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-27 09:10:37 +02:00
Germano Percossi
3d8d2f2344 CIFS: reconnect thread reschedule itself
commit 18ea43113f5b74a97dd4be9bddbac10d68b1a6ce upstream.

In case of error, smb2_reconnect_server reschedule itself
with a delay, to avoid being too aggressive.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-21 09:31:19 +02:00
Jan-Marek Glogowski
8446cb1adf Reset TreeId to zero on SMB2 TREE_CONNECT
commit 806a28efe9b78ffae5e2757e1ee924b8e50c08ab upstream.

Currently the cifs module breaks the CIFS specs on reconnect as
described in http://msdn.microsoft.com/en-us/library/cc246529.aspx:

"TreeId (4 bytes): Uniquely identifies the tree connect for the
command. This MUST be 0 for the SMB2 TREE_CONNECT Request."

Signed-off-by: Jan-Marek Glogowski <glogow@fbihome.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Tested-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:11 +02:00
Pavel Shilovsky
46890ffba1 CIFS: Fix a possible double locking of mutex during reconnect
commit 96a988ffeb90dba33a71c3826086fe67c897a183 upstream.

With the current code it is possible to lock a mutex twice when
a subsequent reconnects are triggered. On the 1st reconnect we
reconnect sessions and tcons and then persistent file handles.
If the 2nd reconnect happens during the reconnecting of persistent
file handles then the following sequence of calls is observed:

cifs_reopen_file -> SMB2_open -> small_smb2_init -> smb2_reconnect
-> cifs_reopen_persistent_file_handles -> cifs_reopen_file (again!).

So, we are trying to acquire the same cfile->fh_mutex twice which
is wrong. Fix this by moving reconnecting of persistent handles to
the delayed work (smb2_reconnect_server) and submitting this work
every time we reconnect tcon in SMB2 commands handling codepath.

This can also lead to corruption of a temporary file list in
cifs_reopen_persistent_file_handles() because we can recursively
call this function twice.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 10:40:16 +01:00
Pavel Shilovsky
69d13b69e7 CIFS: Fix missing nls unload in smb2_reconnect()
commit 4772c79599564bd08ee6682715a7d3516f67433f upstream.

Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 10:40:16 +01:00
Pavel Shilovsky
48f9526f4d CIFS: Fix a possible memory corruption during reconnect
commit 53e0e11efe9289535b060a51d4cf37c25e0d0f2b upstream.

We can not unlock/lock cifs_tcp_ses_lock while walking through ses
and tcon lists because it can corrupt list iterator pointers and
a tcon structure can be released if we don't hold an extra reference.
Fix it by moving a reconnect process to a separate delayed work
and acquiring a reference to every tcon that needs to be reconnected.
Also do not send an echo request on newly established connections.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 10:40:16 +01:00
Sachin Prabhu
166cea4dc3 SMB2: Separate RawNTLMSSP authentication from SMB2_sess_setup
We split the rawntlmssp authentication into negotiate and
authencate parts. We also clean up the code and add helpers.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2016-10-13 19:48:34 -05:00
Sachin Prabhu
3baf1a7b92 SMB2: Separate Kerberos authentication from SMB2_sess_setup
Add helper functions and split Kerberos authentication off
SMB2_sess_setup.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2016-10-13 19:48:30 -05:00
Steve French
141891f472 SMB3: Add mount parameter to allow user to override max credits
Add mount option "max_credits" to allow setting maximum SMB3
credits to any value from 10 to 64000 (default is 32000).
This can be useful to workaround servers with problems allocating
credits, or to throttle the client to use smaller amount of
simultaneous i/o or to workaround server performance issues.

Also adds a cap, so that even if the server granted us more than
65000 credits due to a server bug, we would not use that many.

Signed-off-by: Steve French <steve.french@primarydata.com>
2016-10-12 12:08:33 -05:00
Steve French
52ace1ef12 fs/cifs: reopen persistent handles on reconnect
Continuous Availability features like persistent handles
require that clients reconnect their open files, not
just the sessions, soon after the network connection comes
back up, otherwise the server will throw away the state
(byte range locks, leases, deny modes) on those handles
after a timeout.

Add code to reconnect handles when use_persistent set
(e.g. Continuous Availability shares) after tree reconnect.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Germano Percossi <germano.percossi@citrix.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12 12:08:33 -05:00
Steve French
fa70b87cc6 SMB3: GUIDs should be constructed as random but valid uuids
GUIDs although random, and 16 bytes, need to be generated as
proper uuids.

Signed-off-by: Steve French <steve.french@primarydata.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reported-by: David Goebels <davidgoe@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2016-10-12 12:08:32 -05:00
Steve French
c2afb8147e Set previous session id correctly on SMB3 reconnect
Signed-off-by: Steve French <steve.french@primarydata.com>
CC: Stable <stable@vger.kernel.org>
Reported-by: David Goebel <davidgoe@microsoft.com>
2016-10-12 12:08:31 -05:00
Ross Lagerwall
7d414f396c cifs: Limit the overall credit acquired
The kernel client requests 2 credits for many operations even though
they only use 1 credit (presumably to build up a buffer of credit).
Some servers seem to give the client as much credit as is requested.  In
this case, the amount of credit the client has continues increasing to
the point where (server->credits * MAX_BUFFER_SIZE) overflows in
smb2_wait_mtu_credits().

Fix this by throttling the credit requests if an set limit is reached.
For async requests where the credit charge may be > 1, request as much
credit as what is charged.
The limit is chosen somewhat arbitrarily. The Windows client
defaults to 128 credits, the Windows server allows clients up to
512 credits (or 8192 for Windows 2016), and the NetApp server
(and at least one other) does not limit clients at all.
Choose a high enough value such that the client shouldn't limit
performance.

This behavior was seen with a NetApp filer (NetApp Release 9.0RC2).

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12 12:08:31 -05:00
Steve French
4fcd1813e6 Fix reconnect to not defer smb3 session reconnect long after socket reconnect
Azure server blocks clients that open a socket and don't do anything on it.
In our reconnect scenarios, we can reconnect the tcp session and
detect the socket is available but we defer the negprot and SMB3 session
setup and tree connect reconnection until the next i/o is requested, but
this looks suspicous to some servers who expect SMB3 negprog and session
setup soon after a socket is created.

In the echo thread, reconnect SMB3 sessions and tree connections
that are disconnected.  A later patch will replay persistent (and
resilient) handle opens.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
Acked-by: Pavel Shilovsky <pshilovsky@samba.org>
2016-06-24 12:04:50 -05:00
Jerome Marchand
b8da344b74 cifs: dynamic allocation of ntlmssp blob
In sess_auth_rawntlmssp_authenticate(), the ntlmssp blob is allocated
statically and its size is an "empirical" 5*sizeof(struct
_AUTHENTICATE_MESSAGE) (320B on x86_64). I don't know where this value
comes from or if it was ever appropriate, but it is currently
insufficient: the user and domain name in UTF16 could take 1kB by
themselves. Because of that, build_ntlmssp_auth_blob() might corrupt
memory (out-of-bounds write). The size of ntlmssp_blob in
SMB2_sess_setup() is too small too (sizeof(struct _NEGOTIATE_MESSAGE)
+ 500).

This patch allocates the blob dynamically in
build_ntlmssp_auth_blob().

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
2016-06-23 23:45:07 -05:00
Steve French
897fba1172 remove directory incorrectly tries to set delete on close on non-empty directories
Wrong return code was being returned on SMB3 rmdir of
non-empty directory.

For SMB3 (unlike for cifs), we attempt to delete a directory by
set of delete on close flag on the open. Windows clients set
this flag via a set info (SET_FILE_DISPOSITION to set this flag)
which properly checks if the directory is empty.

With this patch on smb3 mounts we correctly return
 "DIRECTORY NOT EMPTY"
on attempts to remove a non-empty directory.

Signed-off-by: Steve French <steve.french@primarydata.com>
CC: Stable <stable@vger.kernel.org>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
2016-05-17 14:09:44 -05:00
Justin Maggard
deb7deff2f cifs: fix out-of-bounds access in lease parsing
When opening a file, SMB2_open() attempts to parse the lease state from the
SMB2 CREATE Response.  However, the parsing code was not careful to ensure
that the create contexts are not empty or invalid, which can lead to out-
of-bounds memory access.  This can be seen easily by trying
to read a file from a OSX 10.11 SMB3 server.  Here is sample crash output:

BUG: unable to handle kernel paging request at ffff8800a1a77cc6
IP: [<ffffffff8828a734>] SMB2_open+0x804/0x960
PGD 8f77067 PUD 0
Oops: 0000 [#1] SMP
Modules linked in:
CPU: 3 PID: 2876 Comm: cp Not tainted 4.5.0-rc3.x86_64.1+ #14
Hardware name: NETGEAR ReadyNAS 314          /ReadyNAS 314          , BIOS 4.6.5 10/11/2012
task: ffff880073cdc080 ti: ffff88005b31c000 task.ti: ffff88005b31c000
RIP: 0010:[<ffffffff8828a734>]  [<ffffffff8828a734>] SMB2_open+0x804/0x960
RSP: 0018:ffff88005b31fa08  EFLAGS: 00010282
RAX: 0000000000000015 RBX: 0000000000000000 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff88007eb8c8b0
RBP: ffff88005b31fad8 R08: 666666203d206363 R09: 6131613030383866
R10: 3030383866666666 R11: 00000000000002b0 R12: ffff8800660fd800
R13: ffff8800a1a77cc2 R14: 00000000424d53fe R15: ffff88005f5a28c0
FS:  00007f7c8a2897c0(0000) GS:ffff88007eb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff8800a1a77cc6 CR3: 000000005b281000 CR4: 00000000000006e0
Stack:
 ffff88005b31fa70 ffffffff88278789 00000000000001d3 ffff88005f5a2a80
 ffffffff00000003 ffff88005d029d00 ffff88006fde05a0 0000000000000000
 ffff88005b31fc78 ffff88006fde0780 ffff88005b31fb2f 0000000100000fe0
Call Trace:
 [<ffffffff88278789>] ? cifsConvertToUTF16+0x159/0x2d0
 [<ffffffff8828cf68>] smb2_open_file+0x98/0x210
 [<ffffffff8811e80c>] ? __kmalloc+0x1c/0xe0
 [<ffffffff882685f4>] cifs_open+0x2a4/0x720
 [<ffffffff88122cef>] do_dentry_open+0x1ff/0x310
 [<ffffffff88268350>] ? cifsFileInfo_get+0x30/0x30
 [<ffffffff88123d92>] vfs_open+0x52/0x60
 [<ffffffff88131dd0>] path_openat+0x170/0xf70
 [<ffffffff88097d48>] ? remove_wait_queue+0x48/0x50
 [<ffffffff88133a29>] do_filp_open+0x79/0xd0
 [<ffffffff8813f2ca>] ? __alloc_fd+0x3a/0x170
 [<ffffffff881240c4>] do_sys_open+0x114/0x1e0
 [<ffffffff881241a9>] SyS_open+0x19/0x20
 [<ffffffff8896e257>] entry_SYSCALL_64_fastpath+0x12/0x6a
Code: 4d 8d 6c 07 04 31 c0 4c 89 ee e8 47 6f e5 ff 31 c9 41 89 ce 44 89 f1 48 c7 c7 28 b1 bd 88 31 c0 49 01 cd 4c 89 ee e8 2b 6f e5 ff <45> 0f b7 75 04 48 c7 c7 31 b1 bd 88 31 c0 4d 01 ee 4c 89 f6 e8
RIP  [<ffffffff8828a734>] SMB2_open+0x804/0x960
 RSP <ffff88005b31fa08>
CR2: ffff8800a1a77cc6
---[ end trace d9f69ba64feee469 ]---

Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
2016-02-29 00:21:31 -06:00
Steve French
373512ec5c Prepare for encryption support (first part). Add decryption and encryption key generation. Thanks to Metze for helping with this.
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
2016-01-14 14:29:42 -06:00
Linus Torvalds
f3996e6ac6 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull SMB3 updates from Steve French:
 "A collection of SMB3 patches adding some reliability features
  (persistent and resilient handles) and improving SMB3 copy offload.

  I will have some additional patches for SMB3 encryption and SMB3.1.1
  signing (important security features), and also for improving SMB3
  persistent handle reconnection (setting ChannelSequence number e.g.)
  that I am still working on but wanted to get this set in since they
  can stand alone"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  Allow copy offload (CopyChunk) across shares
  Add resilienthandles mount parm
  [SMB3] Send durable handle v2 contexts when use of persistent handles required
  [SMB3] Display persistenthandles in /proc/mounts for SMB3 shares if enabled
  [SMB3] Enable checking for continuous availability and persistent handle support
  [SMB3] Add parsing for new mount option controlling persistent handles
  Allow duplicate extents in SMB3 not just SMB3.1.1
2015-11-13 16:40:36 -08:00
Linus Torvalds
1873499e13 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem update from James Morris:
 "This is mostly maintenance updates across the subsystem, with a
  notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
  maintainer of that"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
  apparmor: clarify CRYPTO dependency
  selinux: Use a kmem_cache for allocation struct file_security_struct
  selinux: ioctl_has_perm should be static
  selinux: use sprintf return value
  selinux: use kstrdup() in security_get_bools()
  selinux: use kmemdup in security_sid_to_context_core()
  selinux: remove pointless cast in selinux_inode_setsecurity()
  selinux: introduce security_context_str_to_sid
  selinux: do not check open perm on ftruncate call
  selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
  KEYS: Merge the type-specific data with the payload data
  KEYS: Provide a script to extract a module signature
  KEYS: Provide a script to extract the sys cert list from a vmlinux file
  keys: Be more consistent in selection of union members used
  certs: add .gitignore to stop git nagging about x509_certificate_list
  KEYS: use kvfree() in add_key
  Smack: limited capability for changing process label
  TPM: remove unnecessary little endian conversion
  vTPM: support little endian guests
  char: Drop owner assignment from i2c_driver
  ...
2015-11-05 15:32:38 -08:00
Steve French
b56eae4df9 [SMB3] Send durable handle v2 contexts when use of persistent handles required
Version 2 of the patch. Thanks to Dan Carpenter and the smatch
tool for finding a problem in the first version of this patch.

CC: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-11-03 09:26:27 -06:00
David Howells
146aa8b145 KEYS: Merge the type-specific data with the payload data
Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net
2015-10-21 15:18:36 +01:00
Steve French
ff9f84b7d7 [SMB3] Missing null tcon check
Pointed out by Dan Carpenter via smatch code analysis tool

CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-09-26 09:48:58 -05:00
Steve French
8862714840 fix encryption error checks on mount
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-09-24 00:53:31 -05:00
Steve French
ceb1b0b9b4 [SMB3] Fix sec=krb5 on smb3 mounts
Kerberos, which is very important for security, was only enabled for
CIFS not SMB2/SMB3 mounts (e.g. vers=3.0)

Patch based on the information detailed in
http://thread.gmane.org/gmane.linux.kernel.cifs/10081/focus=10307
to enable Kerberized SMB2/SMB3

a) SMB2_negotiate: enable/use decode_negTokenInit in SMB2_negotiate
b) SMB2_sess_setup: handle Kerberos sectype and replicate Kerberos
   SMB1 processing done in sess_auth_kerberos

Signed-off-by: Noel Power <noel.power@suse.com>
Signed-off-by: Jim McDonough <jmcd@samba.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-09-24 00:52:37 -05:00
Christopher Oo
5fb4e288a0 cifs: Fix use-after-free on mid_q_entry
With CIFS_DEBUG_2 enabled, additional debug information is tracked inside each
mid_q_entry struct, however cifs_save_when_sent may use the mid_q_entry after it
has been freed from the appropriate callback if the transport layer has very low
latency. Holding the srv_mutex fixes this use-after-free, as cifs_save_when_sent
is called while the srv_mutex is held while the request is sent.

Signed-off-by: Christopher Oo <t-chriso@microsoft.com>
2015-08-20 10:19:25 -05:00
Steve French
ebb3a9d4ba Update negotiate protocol for SMB3.11 dialect
Send negotiate contexts when SMB3.11 dialect is negotiated
(ie the preauth and the encryption contexts) and
Initialize SMB3.11 preauth negotiate context salt to random bytes

Followon patch will update session setup and tree connect

Signed-off-by: Steve French <steve.french@primarydata.com>
2015-06-28 21:15:48 -05:00
Steve French
f799d6234b Make dialect negotiation warning message easier to read
Dialect version and minor version are easier to read in hex

Signed-off-by: Steve French <steve.french@primarydata.com>
2015-06-27 20:28:49 -07:00
Steve French
eed0e1753c Add defines and structs for smb3.1 dialect
Add new structures and defines for SMB3.11 negotiate, session setup and tcon

See MS-SMB2-diff.pdf section 2.2.3 for additional protocol documentation.

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-06-27 20:23:59 -07:00
Steve French
5f7fbf733c Allow parsing vers=3.11 on cifs mount
Parses and recognizes "vers=3.1.1" on cifs mount and allows sending
0x0311 as a new CIFS/SMB3 dialect. Subsequent patches will add
the new negotiate contexts and updated session setup

Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
2015-06-27 20:23:32 -07:00