Commit graph

242 commits

Author SHA1 Message Date
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
Ronnie Sahlberg
f9793b6fcc cifs: change smb2_query_eas to use the compound query-info helper
Reducing the number of network roundtrips improves the performance
of query xattrs

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23 22:40:17 -06:00
Ronnie Sahlberg
07d3b2e426 cifs: create a helper function for compound query_info
and convert statfs to use it.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23 22:38:17 -06:00
Ronnie Sahlberg
0967e54579 cifs: use a compound for setting an xattr
Improve performance by reducing number of network round trips
for set xattr.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23 22:36:24 -06:00
Ronnie Sahlberg
271b9c0c80 smb3: Fix rmdir compounding regression to strict servers
Some servers require that the setinfo matches the exact size,
and in this case compounding changes introduced by
commit c2e0fe3f5a ("cifs: make rmdir() use compounding")
caused us to send 8 bytes (padded length) instead of 1 byte
(the size of the structure).  See MS-FSCC section 2.4.11.

Fixing this when we send a SET_INFO command for delete file
disposition, then ends up as an iov of a single byte but this
causes problems with SMB3 and encryption.

To avoid this, instead of creating a one byte iov for the disposition value
and then appending an additional iov with a 7 byte padding we now handle
this as a single 8 byte iov containing both the disposition byte as well as
the padding in one single buffer.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
2018-12-19 07:55:32 -06:00
Steve French
dfe33f9abc smb3: allow more detailed protocol info on open files for debugging
In order to debug complex problems it is often helpful to
have detailed information on the client and server view
of the open file information.  Add the ability for root to
view the list of smb3 open files and dump the persistent
handle and other info so that it can be more easily
correlated with server logs.

Sample output from "cat /proc/fs/cifs/open_files"

 # Version:1
 # Format:
 # <tree id> <persistent fid> <flags> <count> <pid> <uid> <filename> <mid>
 0x5 0x800000378 0x8000 1 7704 0 some-file 0x14
 0xcb903c0c 0x84412e67 0x8000 1 7754 1001 rofile 0x1a6d
 0xcb903c0c 0x9526b767 0x8000 1 7720 1000 file 0x1a5b
 0xcb903c0c 0x9ce41a21 0x8000 1 7715 0 smallfile 0xd67

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-11-02 14:09:41 -05:00
Ronnie Sahlberg
0c5d6cb664 cifs: fix return value for cifs_listxattr
If the application buffer was too small to fit all the names
we would still count the number of bytes and return this for
listxattr. This would then trigger a BUG in usercopy.c

Fix the computation of the size so that we return -ERANGE
correctly when the buffer is too small.

This fixes the kernel BUG for xfstest generic/377

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-11-02 14:09:41 -05:00
Linus Torvalds
9931a07d51 Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull AFS updates from Al Viro:
 "AFS series, with some iov_iter bits included"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  missing bits of "iov_iter: Separate type from direction and use accessor functions"
  afs: Probe multiple fileservers simultaneously
  afs: Fix callback handling
  afs: Eliminate the address pointer from the address list cursor
  afs: Allow dumping of server cursor on operation failure
  afs: Implement YFS support in the fs client
  afs: Expand data structure fields to support YFS
  afs: Get the target vnode in afs_rmdir() and get a callback on it
  afs: Calc callback expiry in op reply delivery
  afs: Fix FS.FetchStatus delivery from updating wrong vnode
  afs: Implement the YFS cache manager service
  afs: Remove callback details from afs_callback_break struct
  afs: Commit the status on a new file/dir/symlink
  afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
  afs: Don't invoke the server to read data beyond EOF
  afs: Add a couple of tracepoints to log I/O errors
  afs: Handle EIO from delivery function
  afs: Fix TTL on VL server and address lists
  afs: Implement VL server rotation
  afs: Improve FS server rotation error handling
  ...
2018-11-01 19:58:52 -07:00
Steve French
fae8044c03 smb3: show number of current open files in /proc/fs/cifs/Stats
To allow better debugging (for example applications with
handle leaks, or complex reconnect scenarios) display the
number of open files (on the client) and number of open
server file handles for each tcon in /proc/fs/cifs/Stats.
Note that open files on server is one larger than local
due to handle caching (in this case of the root of
the share).  In this example there are two local
open files, and three (two file and one directory handle)
open on the server.

Sample output:

$ cat /proc/fs/cifs/Stats
Resources in use
CIFS Session: 1
Share (unique mount targets): 2
SMB Request/Response Buffer: 1 Pool size: 5
SMB Small Req/Resp Buffer: 1 Pool size: 30
Operations (MIDs): 0

0 session 0 share reconnects
Total vfs operations: 36 maximum at one time: 2

1) \\localhost\test
SMBs: 69
Bytes read: 27  Bytes written: 0
Open files: 2 total (local), 3 open on server
TreeConnects: 1 total 0 failed
TreeDisconnects: 0 total 0 failed
Creates: 19 total 0 failed
Closes: 16 total 0 failed
...

Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:06 -05:00
Ronnie Sahlberg
8d8b26e584 cifs: add support for ioctl on directories
We do not call cifs_open_file() for directories and thus we do not have a
pSMBFile we can extract the FIDs from.

Solve this by instead always using a compounded open/query/close for
the passthrough ioctl.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:05 -05:00
Gustavo A. R. Silva
f70556c8ca smb2: fix uninitialized variable bug in smb2_ioctl_query_info
There is a potential execution path in which variable *resp_buftype*
is passed as an argument to function free_rsp_buf(), in which it is
used in a comparison without being properly initialized previously.

Fix this by initializing variable *resp_buftype* to CIFS_NO_BUFFER
in order to avoid unpredictable or unintended results.

Addresses-Coverity-ID: 1473971 ("Uninitialized scalar variable")
Fixes: c5d25bdb2967 ("cifs: add IOCTL for QUERY_INFO passthrough to userspace")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-10-23 21:16:05 -05:00
Ronnie Sahlberg
f5b05d622a cifs: add IOCTL for QUERY_INFO passthrough to userspace
This allows userspace tools to query the raw info levels for cifs files
and process the response in userspace.
In particular this is useful for many of those data where there is no
corresponding native data structure in linux.
For example querying the security descriptor for a file and extract the
SIDs.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:05 -05:00
Steve French
3d621230b8 smb3: update default requested iosize to 4MB from 1MB for recent dialects
Modern servers often support 8MB as maximum i/o size, and we see some
performance benefits (my testing showed 1 to 13% on write paths,
and 1 to 3% on read paths for increasing the default to 4MB). If server
doesn't support larger i/o size, during negotiate protocol it is already
set correctly to the server's maximum if lower than 4MB.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-10-23 21:16:05 -05:00
Steve French
6e4d3bbe92 smb3: Add debug message later in smb2/smb3 reconnect path
As we reset credits later in the reconnect path, useful
to have optional (cifsFYI) debug message.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-23 21:16:05 -05:00
Steve French
9e1a37dad4 smb3: track the instance of each session for debugging
Each time we reconnect to the same server, bump an instance
counter (and display in /proc/fs/cifs/DebugData) to make it
easier to debug.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-23 21:16:04 -05:00
Ronnie Sahlberg
3764cbd179 cifs: remove the is_falloc argument to SMB2_set_eof
We never pass is_falloc==true here anyway and if we ever need to support
is_falloc in the future, SMB2_set_eof is such a trivial wrapper around
send_set_info() that we can/should just create a differently named wrapper
for that new functionality.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:04 -05:00
Ronnie Sahlberg
c5a5f38f07 cifs: add a smb2_compound_op and change QUERY_INFO to use it
This turns most open/query-info/close patterns in cifs.ko
to become compounds.

This changes stat from using 3 roundtrips to just a single one.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:04 -05:00
Steve French
b340a4d4aa smb3: add tracepoint to catch cases where credit refund of failed op overlaps reconnect
Add tracepoint to catch potential cases where a pending operation overlapping a
reconnect could fail and incorrectly refund its credits causing the client
to think it has more credits available than the server thinks it does.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-10-23 21:16:03 -05:00
David Howells
aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Aurelien Aptel
0595751f26 smb2: fix missing files in root share directory listing
When mounting a Windows share that is the root of a drive (eg. C$)
the server does not return . and .. directory entries. This results in
the smb2 code path erroneously skipping the 2 first entries.

Pseudo-code of the readdir() code path:

cifs_readdir(struct file, struct dir_context)
    initiate_cifs_search            <-- if no reponse cached yet
        server->ops->query_dir_first

    dir_emit_dots
        dir_emit                    <-- adds "." and ".." if we're at pos=0

    find_cifs_entry
        initiate_cifs_search        <-- if pos < start of current response
                                         (restart search)
        server->ops->query_dir_next <-- if pos > end of current response
                                         (fetch next search res)

    for(...)                        <-- loops over cur response entries
                                          starting at pos
        cifs_filldir                <-- skip . and .., emit entry
            cifs_fill_dirent
            dir_emit
	pos++

A) dir_emit_dots() always adds . & ..
   and sets the current dir pos to 2 (0 and 1 are done).

Therefore we always want the index_to_find to be 2 regardless of if
the response has . and ..

B) smb1 code initializes index_of_last_entry with a +2 offset

  in cifssmb.c CIFSFindFirst():
		psrch_inf->index_of_last_entry = 2 /* skip . and .. */ +
			psrch_inf->entries_in_buffer;

Later in find_cifs_entry() we want to find the next dir entry at pos=2
as a result of (A)

	first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
					cfile->srch_inf.entries_in_buffer;

This var is the dir pos that the first entry in the buffer will
have therefore it must be 2 in the first call.

If we don't offset index_of_last_entry by 2 (like in (B)),
first_entry_in_buffer=0 but we were instructed to get pos=2 so this
code in find_cifs_entry() skips the 2 first which is ok for non-root
shares, as it skips . and .. from the response but is not ok for root
shares where the 2 first are actual files

		pos_in_buf = index_to_find - first_entry_in_buffer;
                // pos_in_buf=2
		// we skip 2 first response entries :(
		for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
			/* go entry by entry figuring out which is first */
			cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
						cfile->srch_inf.info_level);
		}

C) cifs_filldir() skips . and .. so we can safely ignore them for now.

Sample program:

int main(int argc, char **argv)
{
	const char *path = argc >= 2 ? argv[1] : ".";
	DIR *dh;
	struct dirent *de;

	printf("listing path <%s>\n", path);
	dh = opendir(path);
	if (!dh) {
		printf("opendir error %d\n", errno);
		return 1;
	}

	while (1) {
		de = readdir(dh);
		if (!de) {
			if (errno) {
				printf("readdir error %d\n", errno);
				return 1;
			}
			printf("end of listing\n");
			break;
		}
		printf("off=%lu <%s>\n", de->d_off, de->d_name);
	}

	return 0;
}

Before the fix with SMB1 on root shares:

<.>            off=1
<..>           off=2
<$Recycle.Bin> off=3
<bootmgr>      off=4

and on non-root shares:

<.>    off=1
<..>   off=4  <-- after adding .., the offsets jumps to +2 because
<2536> off=5       we skipped . and .. from response buffer (C)
<411>  off=6       but still incremented pos
<file> off=7
<fsx>  off=8

Therefore the fix for smb2 is to mimic smb1 behaviour and offset the
index_of_last_entry by 2.

Test results comparing smb1 and smb2 before/after the fix on root
share, non-root shares and on large directories (ie. multi-response
dir listing):

PRE FIX
=======
pre-1-root VS pre-2-root:
        ERR pre-2-root is missing [bootmgr, $Recycle.Bin]
pre-1-nonroot VS pre-2-nonroot:
        OK~ same files, same order, different offsets
pre-1-nonroot-large VS pre-2-nonroot-large:
        OK~ same files, same order, different offsets

POST FIX
========
post-1-root VS post-2-root:
        OK same files, same order, same offsets
post-1-nonroot VS post-2-nonroot:
        OK same files, same order, same offsets
post-1-nonroot-large VS post-2-nonroot-large:
        OK same files, same order, same offsets

REGRESSION?
===========
pre-1-root VS post-1-root:
        OK same files, same order, same offsets
pre-1-nonroot VS post-1-nonroot:
        OK same files, same order, same offsets

BugLink: https://bugzilla.samba.org/show_bug.cgi?id=13107
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Paulo Alcantara <palcantara@suse.deR>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2018-10-02 18:06:21 -05:00
Steve French
f801568332 smb3: check for and properly advertise directory lease support
Although servers will typically ignore unsupported features,
we should advertise the support for directory leases (as
Windows e.g. does) in the negotiate protocol capabilities we
pass to the server, and should check for the server capability
(CAP_DIRECTORY_LEASING) before sending a lease request for an
open of a directory.  This will prevent us from accidentally
sending directory leases to SMB2.1 or SMB2 server for example.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-09-02 23:21:42 -05:00
Steve French
5e19697b56 SMB3: Backup intent flag missing for directory opens with backupuid mounts
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag needs to be set
on opens of directories (and files) but was missing in some
places causing access denied trying to enumerate and backup
servers.

Fixes kernel bugzilla #200953
https://bugzilla.kernel.org/show_bug.cgi?id=200953

Reported-and-tested-by: <whh@rubrik.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-09-02 23:21:42 -05:00
Ronnie Sahlberg
4d8dfafc5c cifs: create a define for how many iovs we need for an SMB2_open()
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-23 15:10:40 -05:00