Commit graph

264 commits

Author SHA1 Message Date
Steve French 89a5bfa350 smb3: optimize open to not send query file internal info
We can cut one third of the traffic on open by not querying the
inode number explicitly via SMB3 query_info since it is now
returned on open in the qfid context.

This is better in multiple ways, and
speeds up file open about 10% (more if network is slow).

Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-18 17:44:13 -05:00
Aurelien Aptel 7e5a70ad88 CIFS: fix deadlock in cached root handling
Prevent deadlock between open_shroot() and
cifs_mark_open_files_invalid() by releasing the lock before entering
SMB2_open, taking it again after and checking if we still need to use
the result.

Link: https://lore.kernel.org/linux-cifs/684ed01c-cbca-2716-bc28-b0a59a0f8521@prodrive-technologies.com/T/#u
Fixes: 3d4ef9a153 ("smb3: fix redundant opens on root")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-07-18 13:51:35 -05:00
Ronnie Sahlberg 88a92c913c cifs: fix crash in smb2_compound_op()/smb2_set_next_command()
RHBZ: 1722704

In low memory situations the various SMB2_*_init() functions can fail
to allocate a request PDU and thus leave the request iovector as NULL.

If we don't check the return code for failure we end up calling
smb2_set_next_command() with a NULL iovector causing a crash when it tries
to dereference it.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-15 21:20:09 -05:00
Ronnie Sahlberg df070afd9b cifs: fix parsing of symbolic link error response
RHBZ: 1672539

In smb2_query_symlink(), if we are parsing the error buffer but it is not something
we recognize as a symlink we should return -EINVAL and not -ENOENT.
I.e. the entry does exist, it is just not something we recognize.

Additionally, add check to verify that that the errortag and the reparsetag all make sense.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-10 16:15:45 -05:00
Ronnie Sahlberg f5f111c231 cifs: refactor and clean up arguments in the reparse point parsing
Will be helpful as we improve handling of special file types.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07 22:37:44 -05:00
Steve French d5ecebc490 smb3: Allow query of symlinks stored as reparse points
The 'NFS' style symlinks (see MS-FSCC 2.1.2.4) were not
being queried properly in query_symlink. Fix this.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-07-07 22:37:43 -05:00
Steve French 73cf8085dc cifs: simplify code by removing CONFIG_CIFS_ACL ifdef
SMB3 ACL support is needed for many use cases now and should not be
ifdeffed out, even for SMB1 (CIFS).  Remove the CONFIG_CIFS_ACL
ifdef so ACL support is always built into cifs.ko

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07 22:37:43 -05:00
Steve French 2b2f754807 SMB3.1.1: Add GCM crypto to the encrypt and decrypt functions
SMB3.1.1 GCM performs much better than the older CCM default:
more than twice as fast in the write patch (copy to the Samba
server on localhost for example) and 80% faster on the read
patch (copy from the server).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-07-07 22:37:42 -05:00
Steve French 9ac63ec776 SMB3: Add SMB3.1.1 GCM to negotiated crypto algorigthms
GCM is faster. Request it during negotiate protocol.
Followon patch will add callouts to GCM crypto

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-07-07 22:37:42 -05:00
Ronnie Sahlberg 5de254dca8 cifs: fix crash querying symlinks stored as reparse-points
We never parsed/returned any data from .get_link() when the object is a windows reparse-point
containing a symlink. This results in the VFS layer oopsing accessing an uninitialized buffer:

...
[  171.407172] Call Trace:
[  171.408039]  readlink_copy+0x29/0x70
[  171.408872]  vfs_readlink+0xc1/0x1f0
[  171.409709]  ? readlink_copy+0x70/0x70
[  171.410565]  ? simple_attr_release+0x30/0x30
[  171.411446]  ? getname_flags+0x105/0x2a0
[  171.412231]  do_readlinkat+0x1b7/0x1e0
[  171.412938]  ? __ia32_compat_sys_newfstat+0x30/0x30
...

Fix this by adding code to handle these buffers and make sure we do return a valid buffer
to .get_link()

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-06-28 00:34:17 -05:00
Thomas Gleixner b6a3d1b71a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 231
Based on 1 normalized pattern(s):

  this library is free software you can redistribute it and or modify
  it under the terms of the gnu general public license v2 as published
  by the free software foundation this library is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu lesser general public license for more details
  you should have received a copy of the gnu lesser general public
  license along with this library if not write to the free software
  foundation inc 59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 2 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.539286961@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:06 +02:00
Ronnie Sahlberg dece44e381 cifs: add support for SEEK_DATA and SEEK_HOLE
Add llseek op for SEEK_DATA and SEEK_HOLE.
Improves xfstests/285,286,436,445,448 and 490

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-15 22:27:53 -05:00
Steve French d1c35afb08 smb3: trivial cleanup to smb2ops.c
Minor cleanup - e.g. missing \n at end of debug statement.

Reported-by: Christoph Probst <kernel@probst.it>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-05-09 13:17:30 -05:00
Christoph Probst a205d5005e cifs: cleanup smb2ops.c and normalize strings
Fix checkpatch warnings/errors in smb2ops.c except "LONG_LINE". Add missing
linebreaks, indentings, __func__. Remove void-returns, unneeded braces.
Address warnings spotted by checkpatch.

Add SPDX License Header.

Add missing "\n" and capitalize first letter in some cifs_dbg() strings.

Signed-off-by: Christoph Probst <kernel@probst.it>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-05-09 13:17:04 -05:00
Ronnie Sahlberg ebaf546a55 SMB3: Clean up query symlink when reparse point
Two of the common symlink formats use reparse points
(unlike mfsymlinks and also unlike the SMB1 posix
extensions).  This is the first part of the fixes
to allow these reparse points (NFS style and Windows
symlinks) to be resolved properly as symlinks by the
client.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Christoph Probst 6a54b2e002 cifs: fix strcat buffer overflow and reduce raciness in smb21_set_oplock_level()
Change strcat to strncpy in the "None" case to fix a buffer overflow
when cinode->oplock is reset to 0 by another thread accessing the same
cinode. It is never valid to append "None" to any other message.

Consolidate multiple writes to cinode->oplock to reduce raciness.

Signed-off-by: Christoph Probst <kernel@probst.it>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-05-07 23:24:55 -05:00
Ronnie Sahlberg c425014afd cifs: fix smb3_zero_range for Azure
For zero-range that also extend the file we were sending this as a
compound of two different operations; a fsctl to set-zero-data for the range
and then an additional set-info to extend the file size.
This does not work for Azure since it does not support this fsctl which leads
to fallocate(FALLOC_FL_ZERO_RANGE) failing but still changing the file size.

To fix this we un-compound this and send these two operations as separate
commands, firsat one command to set-zero-data for the range and it this
was successful we proceed to send a set-info to update the file size.

This fixes xfstest generic/469 for Azure servers.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Ronnie Sahlberg c7fe388d76 cifs: zero-range does not require the file is sparse
Remove the conditional to fail zero-range if the file is not flagged as sparse.
You can still zero out a range in SMB2 even for non-sparse files.

Tested with stock windows16 server.

Fixes 5 xfstests (033, 149, 155, 180, 349)

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Ronnie Sahlberg 2f3ebaba13 cifs: add fiemap support
Useful for improved copy performance as well as for
applications which query allocated ranges of sparse
files.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Ronnie Sahlberg 5242fcb706 cifs: fix bi-directional fsctl passthrough calls
SMB2 Ioctl responses from servers may respond with both the request blob from
the client followed by the actual reply blob for ioctls that are bi-directional.

In that case we can not assume that the reply blob comes immediately after the
ioctl response structure.

This fixes FSCTLs such as SMB2:FSCTL_QUERY_ALLOCATED_RANGES

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Steve French 46e6661963 SMB3: Add handling for different FSCTL access flags
DesiredAccess field in SMB3 open request needs
to be set differently for READ vs. WRITE ioctls
(not just ones that request both).

Originally noticed by Pavel

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-05-07 23:24:55 -05:00
Ronnie Sahlberg efac779b1c cifs: Add support for FSCTL passthrough that write data to the server
Add support to pass a blob to the server in FSCTL passthrough.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Steve French 973189aba6 SMB3: update comment to clarify enumerating snapshots
Trivial update to comment suggested by Pavel.

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:54 -05:00
Ronnie Sahlberg e6d0fb7b34 cifs: fix handle leak in smb2_query_symlink()
If we enter smb2_query_symlink() for something that is not a symlink
and where the SMB2_open() would succeed we would never end up
closing this handle and would thus leak a handle on the server.

Fix this by immediately calling SMB2_close() on successfull open.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-16 09:38:26 -05:00
Ronnie Sahlberg 4811e3096d cifs: a smb2_validate_and_copy_iov failure does not mean the handle is invalid.
It only means that we do not have a valid cached value for the
file_all_info structure.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-01 14:33:38 -05:00
Steve French 153322f753 smb3: Fix enumerating snapshots to Azure
Some servers (see MS-SMB2 protocol specification
section 3.3.5.15.1) expect that the FSCTL enumerate snapshots
is done twice, with the first query having EXACTLY the minimum
size response buffer requested (16 bytes) which refreshes
the snapshot list (otherwise that and subsequent queries get
an empty list returned).  So had to add code to set
the maximum response size differently for the first snapshot
query (which gets the size needed for the second query which
contains the actual list of snapshots).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org> # 4.19+
2019-04-01 14:33:34 -05:00
Ronnie Sahlberg 2f94a3125b cifs: fix kref underflow in close_shroot()
Fix a bug where we used to not initialize the cached fid structure at all
in open_shroot() if the open was successful but we did not get a lease.
This would leave the structure uninitialized and later when we close the handle
we would in close_shroot() try to kref_put() an uninitialized refcount.

Fix this by always initializing this structure if the open was successful
but only do the extra get() if we got a lease.
This extra get() is only used to hold the structure until we get a lease
break from the server at which point we will kref_put() it during lease
processing.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-04-01 14:33:30 -05:00
Ronnie Sahlberg f5778c3987 SMB3: Allow SMB3 FSCTL queries to be sent to server from tools
For debugging purposes we often have to be able to query
additional information only available via SMB3 FSCTL
from the server from user space tools (e.g. like
cifs-utils's smbinfo).  See MS-FSCC and MS-SMB2 protocol
specifications for more details.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:36 -05:00
Ronnie Sahlberg f16994797e cifs: fix incorrect handling of smb2_set_sparse() return in smb3_simple_falloc
smb2_set_sparse does not return -errno, it returns a boolean where
true means success.
Change this to just ignore the return value just like the other callsites.

Additionally add code to handle the case where we must set the file sparse
and possibly also extending it.

Fixes xfstests: generic/236 generic/350 generic/420

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:36 -05:00
Aurelien Aptel c847dccfbd CIFS: make mknod() an smb_version_op
This cleanup removes cifs specific code from SMB2/SMB3 code paths
which is cleaner and easier to maintain as the code to handle
special files is improved.  Below is an example creating special files
using 'sfu' mount option over SMB3 to Windows (with this patch)
(Note that to Samba server, support for saving dos attributes
has to be enabled for the SFU mount option to work).

In the future this will also make implementation of creating
special files as reparse points easier (as Windows NFS server does
for example).

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char
   character special file

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block
   block special file

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:36 -05:00
Steve French 31ba4331d5 SMB3: passthru query info doesn't check for SMB3 FSCTL passthru
The passthrough queries from user space tools like smbinfo can be either
SMB3 QUERY_INFO or SMB3 FSCTL, but we are not checking for the latter.
Temporarily we return EOPNOTSUPP for SMB3 FSCTL passthrough requests
but once compounding fsctls is fixed can enable.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:36 -05:00
Steve French 779ede040d smb3: add dynamic tracepoints for simple fallocate and zero range
Can be helpful in debugging various xfstests that are currently
skipped or failing due to missing features in our current
implementation of fallocate.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg 72c419d9b0 cifs: fix smb3_zero_range so it can expand the file-size when required
This allows fallocate -z to work against a Windows2016 share.

This is due to the SMB3 ZERO_RANGE command does not modify the filesize.
To address this we will now append a compounded SET-INFO to update the
end-of-file information.

This brings xfstests generic/469 closer to working against a windows share.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg b0f6df737a cifs: cache FILE_ALL_INFO for the shared root handle
When we open the shared root handle also ask for FILE_ALL_INFORMATION since
we can do this at zero cost as part of a compound.
Cache this information as long as the lease is held and return and serve any
future requests from cache.

This allows us to serve "stat /<mountpoint>" directly from cache and avoid
a network roundtrip.  Since clients often want to do this quite a lot
this improve performance slightly.

As an example: xfstest generic/533 performs 43 stat operations on the root
of the share while it is run. Which are eliminated with this patch.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg b227d215de cifs: wait_for_free_credits() make it possible to wait for >=1 credits
Change wait_for_free_credits() to allow waiting for >=1 credits instead of just
a single credit.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Pavel Shilovsky 9a1c67e8d5 CIFS: Adjust MTU credits before reopening a file
Currently we adjust MTU credits before sending an IO request
and after reopening a file. This approach doesn't allow the
reopen routine to use existing credits that are not needed
for IO. Reorder credit adjustment and reopening a file to
use credits available to the client more efficiently. Also
unwrap complex if statement into few pieces to improve
readability.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-05 18:10:01 -06:00
Pavel Shilovsky 335b7b62ff CIFS: Respect reconnect in MTU credits calculations
Every time after a session reconnect we don't need to account for
credits obtained in previous sessions. Introduce new struct cifs_credits
which contains both credits value and reconnect instance of the
time those credits were taken. Modify a routine that add credits
back to handle the reconnect instance by assuming zero credits
if the reconnect happened after the credits were obtained and
before we decided to add them back due to some errors during sending.

This patch fixes the MTU credits cases. The subsequent patch
will handle non-MTU ones.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-05 18:10:01 -06:00
Pavel Shilovsky bb1bccb60c CIFS: Respect SMB2 hdr preamble size in read responses
There are a couple places where we still account for 4 bytes
in the beginning of SMB2 packet which is not true in the current
code. Fix this to use a header preamble size where possible.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-04 20:06:39 -06:00
Pavel Shilovsky 66265f134a CIFS: Count SMB3 credits for malformed pending responses
Even if a response is malformed, we should count credits
granted by the server to avoid miscalculations and unnecessary
reconnects due to client or server bugs. If the response has
been received partially, the session will be reconnected anyway
on the next iteration of the demultiplex thread, so counting
credits for such cases shouldn't break things.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-04 20:06:39 -06:00
Pavel Shilovsky 82e0457af5 CIFS: Do not log credits when unmounting a share
Currently we only skip credits logging on reconnects. When
unmounting a share the number of credits on the client doesn't
matter, so skip logging in such cases too.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-04 20:06:39 -06:00
Pavel Shilovsky c781af7e0c CIFS: Do not skip SMB2 message IDs on send failures
When we hit failures during constructing MIDs or sending PDUs
through the network, we end up not using message IDs assigned
to the packet. The next SMB packet will skip those message IDs
and continue with the next one. This behavior may lead to a server
not granting us credits until we use the skipped IDs. Fix this by
reverting the current ID to the original value if any errors occur
before we push the packet through the network stack.

This patch fixes the generic/310 test from the xfs-tests.

Cc: <stable@vger.kernel.org> # 4.19.x
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-04 20:06:12 -06:00
Pavel Shilovsky 7b9b9edb49 CIFS: Do not reset lease state to NONE on lease break
Currently on lease break the client sets a caching level twice:
when oplock is detected and when oplock is processed. While the
1st attempt sets the level to the value provided by the server,
the 2nd one resets the level to None unconditionally.
This happens because the oplock/lease processing code was changed
to avoid races between page cache flushes and oplock breaks.
The commit c11f1df500 ("cifs: Wait for writebacks to complete
before attempting write.") fixed the races for oplocks but didn't
apply the same changes for leases resulting in overwriting the
server granted value to None. Fix this by properly processing
lease breaks.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-03-04 20:05:35 -06:00
Ronnie Sahlberg 2109464184 cifs: return -ENODATA when deleting an xattr that does not exist
BUGZILLA: https://bugzilla.kernel.org/show_bug.cgi?id=202007

When deleting an xattr/EA:
SMB2/3 servers will return SUCCESS when clients delete non-existing EAs.
This means that we need to first QUERY the server and check if the EA
exists or not so that we can return -ENODATA correctly when this happens.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-04 20:05:34 -06:00
Ronnie Sahlberg c4627e66f7 cifs: limit amount of data we request for xattrs to CIFSMaxBufSize
minus the various headers and blobs that will be part of the reply.

or else we might trigger a session reconnect.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-01-29 16:17:25 -06:00
Pavel Shilovsky 3d3003fce8 CIFS: Fix credit calculations in compound mid callback
The current code doesn't do proper accounting for credits
in SMB1 case: it adds one credit per response only if we get
a complete response while it needs to return it unconditionally.
Fix this and also include malformed responses for SMB2+ into
accounting for credits because such responses have Credit
Granted field, thus nothing prevents to get a proper credit
value from them.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-01-24 14:52:06 -06:00
Pavel Shilovsky ec678eae74 CIFS: Fix credit calculation for encrypted reads with errors
We do need to account for credits received in error responses
to read requests on encrypted sessions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-01-24 14:52:05 -06:00
Pavel Shilovsky ef68e83184 CIFS: Do not reconnect TCP session in add_credits()
When executing add_credits() we currently call cifs_reconnect()
if the number of credits is zero and there are no requests in
flight. In this case we may call cifs_reconnect() recursively
twice and cause memory corruption given the following sequence
of functions:

mid1.callback() -> add_credits() -> cifs_reconnect() ->
-> mid2.callback() -> add_credits() -> cifs_reconnect().

Fix this by avoiding to call cifs_reconnect() in add_credits()
and checking for zero credits in the demultiplex thread.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-01-24 14:50:57 -06:00
Pavel Shilovsky acc58d0bab CIFS: Fix possible hang during async MTU reads and writes
When doing MTU i/o we need to leave some credits for
possible reopen requests and other operations happening
in parallel. Currently we leave 1 credit which is not
enough even for reopen only: we need at least 2 credits
if durable handle reconnect fails. Also there may be
other operations at the same time including compounding
ones which require 3 credits at a time each. Fix this
by leaving 8 credits which is big enough to cover most
scenarios.

Was able to reproduce this when server was configured
to give out fewer credits than usual.

The proper fix would be to reconnect a file handle first
and then obtain credits for an MTU request but this leads
to bigger code changes and should happen in other patches.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-01-24 09:37:33 -06:00
Paul Aurich 6d2f84eee0 smb3: fix large reads on encrypted connections
When passing a large read to receive_encrypted_read(), ensure that the
demultiplex_thread knows that a MID was processed.  Without this, those
operations never complete.

This is a similar issue/fix to lease break handling:
commit 7af929d6d0
("smb3: fix lease break problem introduced by compounding")

CC: Stable <stable@vger.kernel.org> # 4.19+
Fixes: b24df3e30c ("cifs: update receive_encrypted_standard to handle compounded responses")
Signed-off-by: Paul Aurich <paul@darkrain42.org>
Tested-by: Yves-Alexis Perez <corsac@corsac.net>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-01-02 23:03:56 -06:00
Ronnie Sahlberg e77fe73c7e cifs: we can not use small padding iovs together with encryption
We can not append small padding buffers as separate iovs when encryption is
used. For this case we must flatten the request into a single buffer
containing both the data from all the iovs as well as the padding bytes.

This is at least needed for 4.20 as well due to compounding changes.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-31 00:58:52 -06:00