Commit Graph

873 Commits

Author SHA1 Message Date
Shyam Prasad N
ba978e8325 cifs: cifs_ses_mark_for_reconnect should also update reconnect bits
Recent restructuring of cifs_reconnect introduced a helper func
named cifs_ses_mark_for_reconnect, which updates the state of tcp
session for all the channels of a session for reconnect.

However, this does not update the session state and chans_need_reconnect
bitmask. This change fixes that.

Also, cifs_mark_tcp_sess_for_reconnect should mark set the bitmask
for all channels when the whole session is marked for reconnect.
Fixed that here too.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:58 -06:00
Shyam Prasad N
47de760655 cifs: update tcpStatus during negotiate and sess setup
Till the end of SMB session setup, update tcpStatus and
avoid updating session status field. There was a typo in
cifs_setup_session, which caused ses->status to be updated
instead. This was causing issues during reconnect.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:55 -06:00
Shyam Prasad N
c1604da708 cifs: make status checks in version independent callers
The status of tcp session, smb session and tcon have the
same flow, irrespective of the SMB version used. Hence
these status checks and updates should happen in the
version independent callers of these commands.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:55 -06:00
Shyam Prasad N
ece0767641 cifs: remove repeated state change in dfs tree connect
cifs_tree_connect checks and sets the tidStatus for the tcon.
cifs_tree_connect also calls a dfs specific tree connect
function, which also does similar checks. This should
not happen. Removing it with this change.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:55 -06:00
Shyam Prasad N
e154cb7b0a cifs: fix the cifs_reconnect path for DFS
Recently, the cifs_reconnect code was refactored into
two branches for regular vs dfs codepath. Some of my
recent changes were missing in the dfs path, namely the
code to enable periodic DNS query, and a missing lock.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:55 -06:00
Shyam Prasad N
88b024f556 cifs: protect all accesses to chan_* with chan_lock
A spin lock called chan_lock was introduced recently.
But not all accesses were protected. Doing that with
this change.

To make sure that a channel is not freed when in use,
we need to introduce a ref count. But today, we don't
ever free channels.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:54 -06:00
Shyam Prasad N
a05885ce13 cifs: fix the connection state transitions with multichannel
Recent changes to multichannel required some adjustments in
the way connection states transitioned during/after reconnect.

Also some minor fixes:
1. A pending switch of GlobalMid_Lock to cifs_tcp_ses_lock
2. Relocations of the code that logs reconnect
3. Changed some code in allocate_mid to suit the new scheme

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:54 -06:00
Shyam Prasad N
3663c9045f cifs: check reconnects for channels of active tcons too
With the new multichannel logic, when a channel needs reconnection,
the tree connect and other channels can still be active.
This fix will handle cases of checking for channel reconnect,
when the tcon does not need reconnect.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-19 11:10:54 -06:00
Eugene Korenevsky
a2809d0e16 cifs: quirk for STATUS_OBJECT_NAME_INVALID returned for non-ASCII dfs refs
Windows SMB server responds with STATUS_OBJECT_NAME_INVALID code to
SMB2 QUERY_INFO request for "\<server>\<dfsname>\<linkpath>" DFS reference,
where <dfsname> contains non-ASCII unicode symbols.

Check such DFS reference and emulate -EREMOTE if it is actual.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215440
Signed-off-by: Eugene Korenevsky <ekorenevsky@astralinux.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-17 13:28:25 -06:00
Linus Torvalds
0c947b893d 13 cifs/smb3 fixes, mostly multichannel, reconnect relate
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Merge tag '5.17-rc-part1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs updates from Steve French:

 - multichannel patches mostly related to improving reconnect behavior

 - minor cleanup patches

* tag '5.17-rc-part1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix FILE_BOTH_DIRECTORY_INFO definition
  cifs: move superblock magic defitions to magic.h
  cifs: Fix smb311_update_preauth_hash() kernel-doc comment
  cifs: avoid race during socket reconnect between send and recv
  cifs: maintain a state machine for tcp/smb/tcon sessions
  cifs: fix hang on cifs_get_next_mid()
  cifs: take cifs_tcp_ses_lock for status checks
  cifs: reconnect only the connection and not smb session where possible
  cifs: add WARN_ON for when chan_count goes below minimum
  cifs: adjust DebugData to use chans_need_reconnect for conn status
  cifs: use the chans_need_reconnect bitmap for reconnect status
  cifs: track individual channel status using chans_need_reconnect
  cifs: remove redundant assignment to pointer p
2022-01-17 09:53:21 +02:00
Linus Torvalds
35ce8ae9ae Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull signal/exit/ptrace updates from Eric Biederman:
 "This set of changes deletes some dead code, makes a lot of cleanups
  which hopefully make the code easier to follow, and fixes bugs found
  along the way.

  The end-game which I have not yet reached yet is for fatal signals
  that generate coredumps to be short-circuit deliverable from
  complete_signal, for force_siginfo_to_task not to require changing
  userspace configured signal delivery state, and for the ptrace stops
  to always happen in locations where we can guarantee on all
  architectures that the all of the registers are saved and available on
  the stack.

  Removal of profile_task_ext, profile_munmap, and profile_handoff_task
  are the big successes for dead code removal this round.

  A bunch of small bug fixes are included, as most of the issues
  reported were small enough that they would not affect bisection so I
  simply added the fixes and did not fold the fixes into the changes
  they were fixing.

  There was a bug that broke coredumps piped to systemd-coredump. I
  dropped the change that caused that bug and replaced it entirely with
  something much more restrained. Unfortunately that required some
  rebasing.

  Some successes after this set of changes: There are few enough calls
  to do_exit to audit in a reasonable amount of time. The lifetime of
  struct kthread now matches the lifetime of struct task, and the
  pointer to struct kthread is no longer stored in set_child_tid. The
  flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
  removed. Issues where task->exit_code was examined with
  signal->group_exit_code should been examined were fixed.

  There are several loosely related changes included because I am
  cleaning up and if I don't include them they will probably get lost.

  The original postings of these changes can be found at:
     https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org

  I trimmed back the last set of changes to only the obviously correct
  once. Simply because there was less time for review than I had hoped"

* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
  ptrace/m68k: Stop open coding ptrace_report_syscall
  ptrace: Remove unused regs argument from ptrace_report_syscall
  ptrace: Remove second setting of PT_SEIZED in ptrace_attach
  taskstats: Cleanup the use of task->exit_code
  exit: Use the correct exit_code in /proc/<pid>/stat
  exit: Fix the exit_code for wait_task_zombie
  exit: Coredumps reach do_group_exit
  exit: Remove profile_handoff_task
  exit: Remove profile_task_exit & profile_munmap
  signal: clean up kernel-doc comments
  signal: Remove the helper signal_group_exit
  signal: Rename group_exit_task group_exec_task
  coredump: Stop setting signal->group_exit_task
  signal: Remove SIGNAL_GROUP_COREDUMP
  signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
  signal: Make coredump handling explicit in complete_signal
  signal: Have prepare_signal detect coredumps using signal->core_state
  signal: Have the oom killer detect coredumps using signal->core_state
  exit: Move force_uaccess back into do_exit
  exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
  ...
2022-01-17 05:49:30 +02:00
Shyam Prasad N
bda487ac4b cifs: avoid race during socket reconnect between send and recv
When a TCP connection gets reestablished by the sender in cifs_reconnect,
There is a chance for race condition with demultiplex thread waiting in
cifs_readv_from_socket on the old socket. It will now return -ECONNRESET.

This condition is handled by comparing socket pointer before and after
sock_recvmsg. If the socket pointer has changed, we should not call
cifs_reconnect again, but instead retry with new socket.

Also fixed another bug in my prev mchan commits.
We should always reestablish session (even if binding) on a channel
that needs reconnection.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-07 20:09:23 -06:00
Shyam Prasad N
73f9bfbe3d cifs: maintain a state machine for tcp/smb/tcon sessions
If functions like cifs_negotiate_protocol, cifs_setup_session,
cifs_tree_connect are called in parallel on different channels,
each of these will be execute the requests. This maybe unnecessary
in some cases, and only the first caller may need to do the work.

This is achieved by having more states for the tcp/smb/tcon session
status fields. And tracking the state of reconnection based on the
state machine.

For example:
for tcp connections:
CifsNew/CifsNeedReconnect ->
  CifsNeedNegotiate ->
    CifsInNegotiate ->
      CifsNeedSessSetup ->
        CifsInSessSetup ->
          CifsGood

for smb sessions:
CifsNew/CifsNeedReconnect ->
  CifsGood

for tcon:
CifsNew/CifsNeedReconnect ->
  CifsInFilesInvalidate ->
    CifsNeedTcon ->
      CifsInTcon ->
        CifsGood

If any channel reconnect sees that it's in the middle of
transition to CifsGood, then they can skip the function.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-07 20:09:22 -06:00
Shyam Prasad N
080dc5e565 cifs: take cifs_tcp_ses_lock for status checks
While checking/updating status for tcp ses, smb ses or tcon,
we take GlobalMid_Lock. This doesn't make any sense.
Replaced it with cifs_tcp_ses_lock.

Ideally, we should take a spin lock per struct.
But since tcp ses, smb ses and tcon objects won't add up to a lot,
I think there should not be too much contention.

Also, in few other places, these are checked without locking.
Added locking for these.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-07 20:07:07 -06:00
Shyam Prasad N
183eea2ee5 cifs: reconnect only the connection and not smb session where possible
With the new per-channel bitmask for reconnect, we have an option to
reconnect the tcp session associated with the channel without reconnecting
the smb session. i.e. if there are still channels to operate on, we can
continue to use the smb session and tcon.

However, there are cases where it makes sense to reconnect the smb session
even when there are active channels underneath. For example for
SMB session expiry.

With this patch, we'll have an option to do either, and use the correct
option for specific cases.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02 20:38:46 -06:00
Shyam Prasad N
f486ef8e20 cifs: use the chans_need_reconnect bitmap for reconnect status
We use the concept of "binding" when one of the secondary channel
is in the process of connecting/reconnecting to the server. Till this
binding process completes, and the channel is bound to an existing session,
we redirect traffic from other established channels on the binding channel,
effectively blocking all traffic till individual channels get reconnected.

With my last set of commits, we can get rid of this binding serialization.
We now have a bitmap of connection states for each channel. We will use
this bitmap instead for tracking channel status.

Having a bitmap also now enables us to keep the session alive, as long
as even a single channel underneath is alive.

Unfortunately, this also meant that we need to supply the tcp connection
info for the channel during all negotiate and session setup functions.
These changes have resulted in a slightly bigger code churn.
However, I expect perf and robustness improvements in the mchan scenario
after this change.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02 20:38:46 -06:00
Shyam Prasad N
d1a931ce2e cifs: track individual channel status using chans_need_reconnect
We needed a way to identify the channels under the smb session
which are in reconnect, so that the traffic to other channels
can continue. So I replaced the bool need_reconnect with
a bitmask identifying all the channels that need reconnection
(named chans_need_reconnect). When a channel needs reconnection,
the bit corresponding to the index of the server in ses->chans
is used to set this bitmask. Checking if no channels or all
the channels need reconnect then becomes very easy.

Also wrote some helper macros for checking and setting the bits.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02 20:38:46 -06:00
Shyam Prasad N
b774302e88 cifs: ignore resource_id while getting fscache super cookie
We have a cyclic dependency between fscache super cookie
and root inode cookie. The super cookie relies on
tcon->resource_id, which gets populated from the root inode
number. However, fetching the root inode initializes inode
cookie as a child of super cookie, which is yet to be populated.

resource_id is only used as auxdata to check the validity of
super cookie. We can completely avoid setting resource_id to
remove the circular dependency. Since vol creation time and
vol serial numbers are used for auxdata, we should be fine.
Additionally, there will be auxiliary data check for each
inode cookie as well.

Fixes: 5bf91ef03d ("cifs: wait for tcon resource_id before getting fscache super")
CC: David Howells <dhowells@redhat.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-12-17 19:09:06 -06:00
Eric W. Biederman
ca3574bd65 exit: Rename module_put_and_exit to module_put_and_kthread_exit
Update module_put_and_exit to call kthread_exit instead of do_exit.

Change the name to reflect this change in functionality.  All of the
users of module_put_and_exit are causing the current kthread to exit
so this change makes it clear what is happening.  There is no
functional change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-13 12:04:45 -06:00
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