Commit graph

854 commits

Author SHA1 Message Date
Shyam Prasad N
2adc82006b cifs: add server conn_id to fscache client cookie
The fscache client cookie uses the server address
(and port) as the cookie key. This is a problem when
nosharesock is used. Two different connections will
use duplicate cookies. Avoid this by adding
server->conn_id to the key, so that it's guaranteed
that cookie will not be duplicated.

Also, for secondary channels of a session, copy the
fscache pointer from the primary channel. The primary
channel is guaranteed not to go away as long as secondary
channels are in use.  Also addresses minor problem found
by kernel test robot.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-03 12:36:04 -06:00
Shyam Prasad N
5bf91ef03d cifs: wait for tcon resource_id before getting fscache super
The logic for initializing tcon->resource_id is done inside
cifs_root_iget. fscache super cookie relies on this for aux
data. So we need to push the fscache initialization to this
later point during mount.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-03 12:29:59 -06:00
Paulo Alcantara
65de262a20 cifs: fix missed refcounting of ipc tcon
Fix missed refcounting of IPC tcon used for getting domain-based DFS
root referrals.  We want to keep it alive as long as mount is active
and can be refreshed.  For standalone DFS root referrals it wouldn't
be a problem as the client ends up having an IPC tcon for both mount
and cache.

Fixes: c88f7dcd6d ("cifs: support nested dfs links over reconnect")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-03 12:29:10 -06:00
Shyam Prasad N
b9ad6b5b68 cifs: nosharesock should be set on new server
Recent fix to maintain a nosharesock state on the
server struct caused a regression. It updated this
field in the old tcp session, and not the new one.

This caused the multichannel scenario to misbehave.

Fixes: c9f1c19cf7 (cifs: nosharesock should not share socket with future sessions)
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-23 10:04:49 -06:00
Paulo Alcantara
8ae87bbeb5 cifs: introduce cifs_ses_mark_for_reconnect() helper
Use new cifs_ses_mark_for_reconnect() helper to mark all session
channels for reconnect instead of duplicating it in different places.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-16 10:57:08 -06:00
Steve French
446e21482e cifs: protect srv_count with cifs_tcp_ses_lock
Updates to the srv_count field are protected elsewhere
with the cifs_tcp_ses_lock spinlock.  Add one missing place
(cifs_get_tcp_sesion).

CC: Shyam Prasad N <sprasad@microsoft.com>
Addresses-Coverity: 1494149 ("Data Race Condition")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-16 10:46:22 -06:00
Shyam Prasad N
46bb1b9484 cifs: do not duplicate fscache cookie for secondary channels
We allocate index cookies for each connection from the client.
However, we don't need this index for each channel in case of
multichannel. So making sure that we avoid creating duplicate
cookies by instantiating only for primary channel.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 23:29:08 -06:00
Shyam Prasad N
0f2b305af9 cifs: connect individual channel servers to primary channel server
Today, we don't have any way to get the smb session for any
of the secondary channels. Introducing a pointer to the primary
server from server struct of any secondary channel. The value will
be NULL for the server of the primary channel. This will enable us
to get the smb session for any channel.

This will be needed for some of the changes that I'm planning
to make soon.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 20:27:06 -06:00
Shyam Prasad N
724244cdb3 cifs: protect session channel fields with chan_lock
Introducing a new spin lock to protect all the channel related
fields in a cifs_ses struct. This lock should be taken
whenever dealing with the channel fields, and should be held
only for very short intervals which will not sleep.

Currently, all channel related fields in cifs_ses structure
are protected by session_mutex. However, this mutex is held for
long periods (sometimes while waiting for a reply from server).
This makes the codepath quite tricky to change.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 16:22:20 -06:00
Shyam Prasad N
8e07757bec cifs: do not negotiate session if session already exists
In cifs_get_smb_ses, if we find an existing matching session,
we should not send a negotiate request for the session if a
session reconnect is not necessary.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 16:21:03 -06:00
Steve French
02102744d3 smb3: do not setup the fscache_super_cookie until fsinfo initialized
We were calling cifs_fscache_get_super_cookie after tcon but before
we queried the info (QFS_Info) we need to initialize the cookie
properly.  Also includes an additional check suggested by Paulo
to make sure we don't initialize super cookie twice.

Suggested-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 13:10:33 -06:00
Paulo Alcantara
7f28af9cf5 cifs: fix potential use-after-free bugs
Ensure that share and prefix variables are set to NULL after kfree()
when looping through DFS targets in __tree_connect_dfs_target().

Also, get rid of @ref in __tree_connect_dfs_target() and just pass a
boolean to indicate whether we're handling link targets or not.

Fixes: c88f7dcd6d ("cifs: support nested dfs links over reconnect")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 12:59:59 -06:00
Steve French
9e7ffa77b2 cifs: release lock earlier in dequeue_mid error case
In dequeue_mid we can log an error while holding a spinlock,
GlobalMid_Lock.  Coverity notes that the error logging
also grabs a lock so it is cleaner (and a bit safer) to
release the GlobalMid_Lock before logging the warning.

Addresses-Coverity: 1507573 ("Thread deadlock")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-12 12:59:51 -06:00
Steve French
0e62904836 smb3: remove trivial dfs compile warning
Fix warning caused by recent changes to the dfs code:

symbol 'tree_connect_dfs_target' was not declared. Should it be static?

Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-10 16:30:23 -06:00
Paulo Alcantara
c88f7dcd6d cifs: support nested dfs links over reconnect
Mounting a dfs link that has nested links was already supported at
mount(2), so make it work over reconnect as well.

Make the following case work:

* mount //root/dfs/link /mnt -o ...
  - final share: /server/share

* in server settings
  - change target folder of /root/dfs/link3 to /server/share2
  - change target folder of /root/dfs/link2 to /root/dfs/link3
  - change target folder of /root/dfs/link to /root/dfs/link2

* mount -o remount,... /mnt
 - refresh all dfs referrals
 - mark current connection for failover
 - cifs_reconnect() reconnects to root server
 - tree_connect()
   * checks that /root/dfs/link2 is a link, then chase it
   * checks that root/dfs/link3 is a link, then chase it
   * finally tree connect to /server/share2

If the mounted share is no longer accessible and a reconnect had been
triggered, the client will retry it from both last referral
path (/root/dfs/link3) and original referral path (/root/dfs/link).

Any new referral paths found while chasing dfs links over reconnect,
it will be updated to TCP_Server_Info::leaf_fullpath, accordingly.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-10 16:30:13 -06:00
Paulo Alcantara
4ac0536f88 cifs: set a minimum of 120s for next dns resolution
With commit 506c1da44f ("cifs: use the expiry output of dns_query to
schedule next resolution") and after triggering the first reconnect,
the next async dns resolution of tcp server's hostname would be
scheduled based on dns_resolver's key expiry default, which happens to
default to 5s on most systems that use key.dns_resolver for upcall.

As per key.dns_resolver.conf(5):

       default_ttl=<number>
              The  number  of  seconds  to  set  as the expiration on a cached
              record.  This will be overridden if the program manages  to  re-
              trieve  TTL  information along with the addresses (if, for exam-
              ple, it accesses the DNS directly).  The default is  5  seconds.
              The value must be in the range 1 to INT_MAX.

Make the next async dns resolution no shorter than 120s as we do not
want to be upcalling too often.

Cc: stable@vger.kernel.org
Fixes: 506c1da44f ("cifs: use the expiry output of dns_query to schedule next resolution")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09 23:03:08 -06:00
Paulo Alcantara
bbcce36804 cifs: split out dfs code from cifs_reconnect()
Make two separate functions that handle dfs and non-dfs reconnect
logics since cifs_reconnect() became way too complex to handle both.
While at it, add some documentation.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09 23:01:55 -06:00
Paulo Alcantara
ae0abb4dac cifs: convert list_for_each to entry variant
Convert list_for_each{,_safe} to list_for_each_entry{,_safe} in
cifs_mark_tcp_ses_conns_for_reconnect() function.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09 20:46:36 -06:00
Paulo Alcantara
43b459aa5e cifs: introduce new helper for cifs_reconnect()
Create cifs_mark_tcp_ses_conns_for_reconnect() helper to mark all
sessions and tcons for reconnect when reconnecting tcp server.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-09 20:46:08 -06:00
Shyam Prasad N
49bd49f983 cifs: send workstation name during ntlmssp session setup
During the ntlmssp session setup (authenticate phases)
send the client workstation info. This can make debugging easier on
servers.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-08 13:07:56 -06:00
Shyam Prasad N
c9f1c19cf7 cifs: nosharesock should not share socket with future sessions
Today, when a new mount is done with nosharesock, we ensure
that we don't select an existing matching session. However,
we don't mark the connection as nosharesock, which means that
those could be shared with future sessions.

Fixed it with this commit. Also printing this info in DebugData.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-07 00:09:37 -05:00
Steve French
d7171cd1ac smb3: add dynamic trace points for socket connection
In debugging user problems with ip address/DNS issues with
smb3 mounts, we sometimes needed additional info on the hostname
and ip address.

Add two tracepoints, one to show socket connection success
and one for failures to connect to the socket.

Sample output:
      mount.cifs-14551   [005] .....  7636.547906: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445
      mount.cifs-14558   [004] .....  7642.405413: smb3_connect_done: conn_id=0x2 server=smfrench.file.core.windows.net addr=52.239.158.232:445
      mount.cifs-14741   [005] .....  7818.490716: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0
      mount.cifs-14810   [000] .....  7966.380337: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:445/0%0
      mount.cifs-14810   [000] .....  7966.380356: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:139/0%0
      mount.cifs-14818   [003] .....  7986.771992: smb3_connect_done: conn_id=0x5 server=127.0.0.9 addr=127.0.0.9:445
      mount.cifs-14825   [008] .....  8008.178109: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:445
      mount.cifs-14825   [008] .....  8013.298085: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:139
           cifsd-14553   [006] .....  8036.735615: smb3_reconnect: conn_id=0x1 server=localhost current_mid=32
           cifsd-14743   [010] .....  8036.735644: smb3_reconnect: conn_id=0x3 server=::1 current_mid=29
           cifsd-14743   [010] .....  8039.921740: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0
           cifsd-14553   [008] .....  8042.993894: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445
           cifsd-14743   [010] .....  8042.993894: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0
           cifsd-14553   [008] .....  8046.065824: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445
           cifsd-14743   [010] .....  8046.065824: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0
           cifsd-14553   [008] .....  8049.137796: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445
           cifsd-14743   [010] .....  8049.137796: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0

Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 16:20:24 -05:00
Ronnie Sahlberg
0d35e382e4 cifs: Create a new shared file holding smb2 pdu definitions
This file will contain all the definitions we need for SMB2 packets
and will follow the naming convention of MS-SMB2.PDF as closely
as possible to make it easier to cross-reference beween the definitions
and the standard.

The content of this file will mostly consist of migration of existing
definitions in the cifs/smb2.pdu.h and ksmbd/smb2pdu.h files
with some additional tweaks as the two files have diverged.

This patch introduces the new smbfs_common/smb2pdu.h file
and migrates the SMB2 header as well as TREE_CONNECT and TREE_DISCONNECT
to the shared file.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 09:50:57 -05:00
Shyam Prasad N
7be3248f31 cifs: To match file servers, make sure the server hostname matches
We generally rely on a bunch of factors to differentiate between servers.
For example, IP address, port etc.

For certain server types (like Azure), it is important to make sure
that the server hostname matches too, even if the both hostnames currently
resolve to the same IP address.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-02 13:12:55 -05:00
Steve French
9ed38fd4a1 cifs: fix incorrect check for null pointer in header_assemble
Although very unlikely that the tlink pointer would be null in this case,
get_next_mid function can in theory return null (but not an error)
so need to check for null (not for IS_ERR, which can not be returned
here).

Address warning:

        fs/smbfs_client/connect.c:2392 cifs_match_super()
        warn: 'tlink' isn't an ERR_PTR

Pointed out by Dan Carpenter via smatch code analysis tool

CC: stable@vger.kernel.org
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-23 21:12:53 -05:00
Steve French
4c51de1e8f cifs: fix incorrect kernel doc comments
Correct kernel-doc comments pointed out by the
automated kernel test robot.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-13 18:29:46 -05:00
Steve French
099dd788e3 cifs: remove pathname for file from SPDX header
checkpatch complains about source files with filenames (e.g. in
these cases just below the SPDX header in comments at the top of
various files in fs/cifs). It also is helpful to change this now
so will be less confusing when the parent directory is renamed
e.g. from fs/cifs to fs/smb_client (or fs/smbfs)

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-13 14:51:10 -05:00
Ronnie Sahlberg
76a3c92ec9 cifs: remove support for NTLM and weaker authentication algorithms
for SMB1.
This removes the dependency to DES.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-08-25 15:47:06 -05:00
Paulo Alcantara
b62366181a cifs: support share failover when remounting
When remouting a DFS share, force a new DFS referral of the path and
if the currently cached targets do not match any of the new targets or
there was no cached targets, then mark it for reconnect.

For example:

    $ mount //dom/dfs/link /mnt -o username=foo,password=bar
    $ ls /mnt
    oldfile.txt

    change target share of 'link' in server settings

    $ mount /mnt -o remount,username=foo,password=bar
    $ ls /mnt
    newfile.txt

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-22 11:43:23 -05:00
Paulo Alcantara
cdc3363065 cifs: do not share tcp sessions of dfs connections
Make sure that we do not share tcp sessions of dfs mounts when
mounting regular shares that connect to same server.  DFS connections
rely on a single instance of tcp in order to do failover properly in
cifs_reconnect().

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-16 00:21:47 -05:00
Shyam Prasad N
16dd9b8c31 cifs: added WARN_ON for all the count decrements
We have a few ref counters srv_count, ses_count and
tc_count which we use for ref counting. Added a WARN_ON
during the decrement of each of these counters to make
sure that they don't go below their minimum values.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-15 19:07:00 -05:00
Steve French
63f94e946f cifs: fix missing null session check in mount
Although it is unlikely to be have ended up with a null
session pointer calling cifs_try_adding_channels in cifs_mount.
Coverity correctly notes that we are already checking for
it earlier (when we return from do_dfs_failover), so at
a minimum to clarify the code we should make sure we also
check for it when we exit the loop so we don't end up calling
cifs_try_adding_channels or mount_setup_tlink with a null
ses pointer.

Addresses-Coverity: 1505608 ("Derefernce after null check")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-15 19:06:57 -05:00
Paulo Alcantara
507345b5ae cifs: handle reconnect of tcon when there is no cached dfs referral
When there is no cached DFS referral of tcon->dfs_path, then reconnect
to same share.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-15 19:06:45 -05:00
Shyam Prasad N
506c1da44f cifs: use the expiry output of dns_query to schedule next resolution
We recently fixed DNS resolution of the server hostname during reconnect.
However, server IP address may change, even when the old one continues
to server (although sub-optimally).

We should schedule the next DNS resolution based on the TTL of
the DNS record used for the last resolution. This way, we resolve the
server hostname again when a DNS record expires.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-14 10:06:03 -05:00
Steve French
01cf30825c cifs: make locking consistent around the server session status
There were three places where we were not taking the spinlock
around updates to server->tcpStatus when it was being modified.
To be consistent (also removes Coverity warning) and to remove
possibility of race best to lock all places where it is updated.
Two of the three were in initialization of the field and can't
race - but added lock around the other.

Addresses-Coverity: 1399512 ("Data race condition")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-02 18:35:25 -05:00
Steve French
0060a4f28a cifs: fix missing spinlock around update to ses->status
In the other places where we update ses->status we protect the
updates via GlobalMid_Lock. So to be consistent add the same
locking around it in cifs_put_smb_ses where it was missing.

Addresses-Coverity: 1268904 ("Data race condition")
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-24 16:09:10 -05:00
Steve French
162004a2f7 cifs: missing null pointer check in cifs_mount
We weren't checking if tcon is null before setting dfs path,
although we check for null tcon in an earlier assignment statement.

Addresses-Coverity: 1476411 ("Dereference after null check")
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-23 19:32:24 -05:00
Steve French
929be906fa cifs: use SPDX-Licence-Identifier
Add SPDX license identifier and replace license boilerplate.
Corrects various checkpatch errors with the older format for
noting the LGPL license.

Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:17 -05:00
Paulo Alcantara
f3c852b0b0 cifs: do not share tcp servers with dfs mounts
It isn't enough to have unshared tcons because multiple DFS mounts can
connect to same target server and failover to different servers, so we
can't use a single tcp server for such cases.

For the simplest solution, use nosharesock option to achieve that.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:17 -05:00
Paulo Alcantara
c870a8e70e cifs: handle different charsets in dfs cache
Convert all dfs paths to dfs cache's local codepage (@cache_cp) and
avoid mixing them with different charsets.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:16 -05:00
Paulo Alcantara
c9f7110399 cifs: keep referral server sessions alive
At every mount, keep all sessions alive that were used for chasing the
DFS referrals as long as the dfs mounts are active.

Use those sessions in DFS cache to refresh all active tcons as well as
cached entries.  They will be managed by a list of mount_group
structures that will be indexed by a randomly generated uuid at mount
time, so we can put all the sessions related to specific dfs mounts
and avoid leaking them.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:16 -05:00
Paulo Alcantara
f3191fc800 cifs: do not send tree disconnect to ipc shares
On session close, the IPC is closed and the server must release all
tcons of the session.  It doesn't matter if we send a ipc close or
not.

Besides, it will make the server to not close durable and resilient
files on session close, as specified in MS-SMB2 3.3.5.6 Receiving an
SMB2 LOGOFF Request.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:16 -05:00
Paulo Alcantara
5c1acf3fe0 cifs: fix regression when mounting shares with prefix paths
The commit 315db9a05b ("cifs: fix leak in cifs_smb3_do_mount() ctx")
revealed an existing bug when mounting shares that contain a prefix
path or DFS links.

cifs_setup_volume_info() requires the @devname to contain the full
path (UNC + prefix) to update the fs context with the new UNC and
prepath values, however we were passing only the UNC
path (old_ctx->UNC) in @device thus discarding any prefix paths.

Instead of concatenating both old_ctx->{UNC,prepath} and pass it in
@devname, just keep the dup'ed values of UNC and prepath in
cifs_sb->ctx after calling smb3_fs_context_dup(), and fix
smb3_parse_devname() to correctly parse and not leak the new UNC and
prefix paths.

Cc: <stable@vger.kernel.org> # v5.11+
Fixes: 315db9a05b ("cifs: fix leak in cifs_smb3_do_mount() ctx")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-05-04 11:52:56 -05:00
Shyam Prasad N
5b2abdafbe cifs: use echo_interval even when connection not ready.
When the tcp connection is not ready to send requests,
we keep retrying echo with an interval of zero.

This seems unnecessary, and this fix changes the interval
between echoes to what is specified as echo_interval.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-05-03 11:54:29 -05:00
Shyam Prasad N
f4916649f9 cifs: detect dead connections only when echoes are enabled.
We can detect server unresponsiveness only if echoes are enabled.
Echoes can be disabled under two scenarios:
1. The connection is low on credits, so we've disabled echoes/oplocks.
2. The connection has not seen any request till now (other than
negotiate/sess-setup), which is when we enable these two, based on
the credits available.

So this fix will check for dead connection, only when echo is enabled.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
CC: <stable@vger.kernel.org> # v5.8+
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-05-03 11:49:13 -05:00
Al Viro
8d76722355 cifs: don't cargo-cult strndup()
strndup(s, strlen(s)) is a highly unidiomatic way to spell strdup(s);
it's *NOT* safer in any way, since strlen() is just as sensitive to
NUL-termination as strdup() is.

strndup() is for situations when you need a copy of a known-sized
substring, not a magic security juju to drive the bad spirits away.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-04-25 16:28:23 -05:00
Aurelien Aptel
b7fd0fa0ea cifs: simplify SWN code with dummy funcs instead of ifdefs
This commit doesn't change the logic of SWN.

Add dummy implementation of SWN functions when SWN is disabled instead
of using ifdef sections.

The dummy functions get optimized out, this leads to clearer code and
compile time type-checking regardless of config options with no
runtime penalty.

Leave the simple ifdefs section as-is.

A single bitfield (bool foo:1) on its own will use up one int. Move
tcon->use_witness out of ifdefs with the other tcon bitfields.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Samuel Cabrero <scabrero@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-04-25 16:28:22 -05:00
Shyam Prasad N
4e456b30f7 cifs: On cifs_reconnect, resolve the hostname again.
On cifs_reconnect, make sure that DNS resolution happens again.
It could be the cause of connection to go dead in the first place.

This also contains the fix for a build issue identified by Intel bot.
Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: <stable@vger.kernel.org> # 5.11+
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-04-07 21:29:36 -05:00
Paulo Alcantara
bf1bc694b6 cifs: print MIDs in decimal notation
The MIDs are mostly printed as decimal, so let's make it consistent.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:22:31 -06:00
Aurelien Aptel
a249cc8bc2 cifs: fix credit accounting for extra channel
With multichannel, operations like the queries
from "ls -lR" can cause all credits to be used and
errors to be returned since max_credits was not
being set correctly on the secondary channels and
thus the client was requesting 0 credits incorrectly
in some cases (which can lead to not having
enough credits to perform any operation on that
channel).

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 11:35:57 -06:00