Commit Graph

221 Commits

Author SHA1 Message Date
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
Ronnie Sahlberg c1777df1a5 cifs: add missing support for ACLs in SMB 3.11
We were missing the methods for get_acl and friends for the 3.11
dialect.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-10 11:53:32 -05:00
Steve French e02789a53d smb3: enumerating snapshots was leaving part of the data off end
When enumerating snapshots, the last few bytes of the final
snapshot could be left off since we were miscalculating the
length returned (leaving off the sizeof struct SRV_SNAPSHOT_ARRAY)
See MS-SMB2 section 2.2.32.2. In addition fixup the length used
to allow smaller buffer to be passed in, in order to allow
returning the size of the whole snapshot array more easily.

Sample userspace output with a kernel patched with this
(mounted to a Windows volume with two snapshots).
Before this patch, the second snapshot would be missing a
few bytes at the end.

~/cifs-2.6# ~/enum-snapshots /mnt/file
press enter to issue the ioctl to retrieve snapshot information ...

size of snapshot array = 102
Num snapshots: 2 Num returned: 2 Array Size: 102

Snapshot 0:@GMT-2018.06.30-19.34.17
Snapshot 1:@GMT-2018.06.30-19.33.37

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-09 21:20:01 -05:00
Ronnie Sahlberg 730928c8f4 cifs: update smb2_queryfs() to use compounding
Change smb2_queryfs() to use a Create/QueryInfo/Close compound request.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-09 21:19:56 -05:00
Ronnie Sahlberg b24df3e30c cifs: update receive_encrypted_standard to handle compounded responses
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-09 21:19:45 -05:00
Ronnie Sahlberg b2c96de7fe cifs: update init_sg, crypt_message to take an array of rqst
These are used for SMB3 encryption and compounded requests.
Update these functions and the other functions related to SMB3 encryption to
take an array of requests.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-07 14:21:18 -05:00
Steve French 52ce1ac429 smb3: display bytes_read and bytes_written in smb3 stats
We were only displaying bytes_read and bytes_written in cifs
stats, fix smb3 stats to also display them.  Sample output
with this patch:

    cat /proc/fs/cifs/Stats:

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: 94 maximum at one time: 2

1) \\localhost\test
SMBs: 214
Bytes read: 502092  Bytes written: 31457286
TreeConnects: 1 total 0 failed
TreeDisconnects: 0 total 0 failed
Creates: 52 total 3 failed
Closes: 48 total 0 failed
Flushes: 0 total 0 failed
Reads: 17 total 0 failed
Writes: 31 total 0 failed
...

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07 14:20:22 -05:00
Steve French fcabb89299 cifs: simple stats should always be enabled
CONFIG_CIFS_STATS should always be enabled as Pavel recently
noted.  Simple statistics are not a significant performance hit,
and removing the ifdef simplifies the code slightly.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-07 14:20:22 -05:00
Ronnie Sahlberg 9da6ec7775 cifs: use a refcount to protect open/closing the cached file handle
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Cc: <stable@vger.kernel.org>
2018-08-07 14:20:22 -05:00
Steve French e68a932b0b smb3: add tracepoint for session expired or deleted
In debugging reconnection problems, want to be able to more easily
trace cases in which the server has marked the SMB3 session
expired or deleted (to distinguish from timeout cases).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07 14:15:57 -05:00
Steve French 1995d28f84 smb3: remove per-session operations from per-tree connection stats
Remove counters from the per-tree connection /proc/fs/cifs/Stats
output that will always be zero (since they are not per-tcon ops)
ie SMB3 Negotiate, SessionSetup, Logoff, Echo, Cancel.

Also clarify "sent" to be "total" per-Pavel's suggestion
(since this "total" includes total for all operations that we try to
send whether or not succesffully sent). Sample output below:

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

1 session 2 share reconnects
Total vfs operations: 23 maximum at one time: 2

1) \\localhost\test
SMBs: 45
TreeConnects: 2 total 0 failed
TreeDisconnects: 0 total 0 failed
Creates: 13 total 2 failed
Closes: 9 total 0 failed
Flushes: 0 total 0 failed
Reads: 0 total 0 failed
Writes: 1 total 0 failed
Locks: 0 total 0 failed
IOCTLs: 3 total 1 failed
QueryDirectories: 4 total 2 failed
ChangeNotifies: 0 total 0 failed
QueryInfos: 10 total 0 failed
SetInfos: 3 total 0 failed
OplockBreaks: 0 sent 0 failed

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-07 14:15:56 -05:00
Steve French c3ed44026c smb3: remove noisy warning message on mount
Some servers, like Samba, don't support the fsctl for
query_network_interface_info so don't log a noisy warning
message on mount for this by default unless the error is more serious.
Lower the error to an FYI level so it does not get logged by
default.

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-07 14:15:56 -05:00
Steve French 0fdfef9aa7 smb3: simplify code by removing CONFIG_CIFS_SMB311
We really, really want to be encouraging use of secure dialects,
and SMB3.1.1 offers useful security features, and will soon
be the recommended dialect for many use cases. Simplify the code
by removing the CONFIG_CIFS_SMB311 ifdef so users don't disable
it in the build, and create compatibility and/or security issues
with modern servers - many of which have been supporting this
dialect for multiple years.

Also clarify some of the Kconfig text for cifs.ko about
SMB3.1.1 and current supported features in the module.

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07 14:15:56 -05:00
Steve French 2d30421783 smb3: add support for statfs for smb3.1.1 posix extensions
Output now matches expected stat -f output for all fields
except for Namelen and ID which were addressed in a companion
patch (which retrieves them from existing SMB3 mechanisms
and works whether POSIX enabled or not)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-08-07 14:15:41 -05:00
Steve French 21ba3845b5 smb3: fill in statfs fsid and correct namelen
Fil in the correct namelen (typically 255 not 4096) in the
statfs response and also fill in a reasonably unique fsid
(in this case taken from the volume id, and the creation time
of the volume).

In the case of the POSIX statfs all fields are now filled in,
and in the case of non-POSIX mounts, all fields are filled
in which can be.

Signed-off-by: Steve French <stfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-08-07 14:15:41 -05:00
Dan Carpenter ff361fda55 cifs: Silence uninitialized variable warning
This is not really a runtime issue but Smatch complains that:

    fs/cifs/smb2ops.c:1740 smb2_query_symlink()
    error: uninitialized symbol 'resp_buftype'.

The warning is right that it can be uninitialized...  Also "err_buf"
would be NULL at this point and we're not supposed to pass NULLs to
free_rsp_buf() or it might trigger some extra output if we turn on
debugging.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-07 14:15:41 -05:00
Stefano Brivio 729c0c9dd5 cifs: Fix stack out-of-bounds in smb{2,3}_create_lease_buf()
smb{2,3}_create_lease_buf() store a lease key in the lease
context for later usage on a lease break.

In most paths, the key is currently sourced from data that
happens to be on the stack near local variables for oplock in
SMB2_open() callers, e.g. from open_shroot(), whereas
smb2_open_file() properly allocates space on its stack for it.

The address of those local variables holding the oplock is then
passed to create_lease_buf handlers via SMB2_open(), and 16
bytes near oplock are used. This causes a stack out-of-bounds
access as reported by KASAN on SMB2.1 and SMB3 mounts (first
out-of-bounds access is shown here):

[  111.528823] BUG: KASAN: stack-out-of-bounds in smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.530815] Read of size 8 at addr ffff88010829f249 by task mount.cifs/985
[  111.532838] CPU: 3 PID: 985 Comm: mount.cifs Not tainted 4.18.0-rc3+ #91
[  111.534656] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[  111.536838] Call Trace:
[  111.537528]  dump_stack+0xc2/0x16b
[  111.540890]  print_address_description+0x6a/0x270
[  111.542185]  kasan_report+0x258/0x380
[  111.544701]  smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.546134]  SMB2_open+0x1ef8/0x4b70 [cifs]
[  111.575883]  open_shroot+0x339/0x550 [cifs]
[  111.591969]  smb3_qfs_tcon+0x32c/0x1e60 [cifs]
[  111.617405]  cifs_mount+0x4f3/0x2fc0 [cifs]
[  111.674332]  cifs_smb3_do_mount+0x263/0xf10 [cifs]
[  111.677915]  mount_fs+0x55/0x2b0
[  111.679504]  vfs_kern_mount.part.22+0xaa/0x430
[  111.684511]  do_mount+0xc40/0x2660
[  111.698301]  ksys_mount+0x80/0xd0
[  111.701541]  do_syscall_64+0x14e/0x4b0
[  111.711807]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  111.713665] RIP: 0033:0x7f372385b5fa
[  111.715311] Code: 48 8b 0d 99 78 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 66 78 2c 00 f7 d8 64 89 01 48
[  111.720330] RSP: 002b:00007ffff27049d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[  111.722601] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f372385b5fa
[  111.724842] RDX: 000055c2ecdc73b2 RSI: 000055c2ecdc73f9 RDI: 00007ffff270580f
[  111.727083] RBP: 00007ffff2705804 R08: 000055c2ee976060 R09: 0000000000001000
[  111.729319] R10: 0000000000000000 R11: 0000000000000206 R12: 00007f3723f4d000
[  111.731615] R13: 000055c2ee976060 R14: 00007f3723f4f90f R15: 0000000000000000

[  111.735448] The buggy address belongs to the page:
[  111.737420] page:ffffea000420a7c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[  111.739890] flags: 0x17ffffc0000000()
[  111.741750] raw: 0017ffffc0000000 0000000000000000 dead000000000200 0000000000000000
[  111.744216] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[  111.746679] page dumped because: kasan: bad access detected

[  111.750482] Memory state around the buggy address:
[  111.752562]  ffff88010829f100: 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00
[  111.754991]  ffff88010829f180: 00 00 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
[  111.757401] >ffff88010829f200: 00 00 00 00 00 f1 f1 f1 f1 01 f2 f2 f2 f2 f2 f2
[  111.759801]                                               ^
[  111.762034]  ffff88010829f280: f2 02 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
[  111.764486]  ffff88010829f300: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  111.766913] ==================================================================

Lease keys are however already generated and stored in fid data
on open and create paths: pass them down to the lease context
creation handlers and use them.

Suggested-by: Aurélien Aptel <aaptel@suse.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Fixes: b8c32dbb0d ("CIFS: Request SMB2.1 leases")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-07-05 13:48:25 -05:00
Paulo Alcantara 6aa0c114ec cifs: Fix memory leak in smb2_set_ea()
This patch fixes a memory leak when doing a setxattr(2) in SMB2+.

Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-07-05 13:48:24 -05:00
Ronnie Sahlberg 81f39f951b cifs: fix SMB1 breakage
SMB1 mounting broke in commit 35e2cc1ba7
("cifs: Use correct packet length in SMB2_TRANSFORM header")
Fix it and also rename smb2_rqst_len to smb_rqst_len
to make it less unobvious that the function is also called from
CIFS/SMB1

Good job by Paulo reviewing and cleaning up Ronnie's original patch.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-07-05 13:48:24 -05:00
Lars Persson 696e420bb2 cifs: Fix use after free of a mid_q_entry
With protocol version 2.0 mounts we have seen crashes with corrupt mid
entries. Either the server->pending_mid_q list becomes corrupt with a
cyclic reference in one element or a mid object fetched by the
demultiplexer thread becomes overwritten during use.

Code review identified a race between the demultiplexer thread and the
request issuing thread. The demultiplexer thread seems to be written
with the assumption that it is the sole user of the mid object until
it calls the mid callback which either wakes the issuer task or
deletes the mid.

This assumption is not true because the issuer task can be woken up
earlier by a signal. If the demultiplexer thread has proceeded as far
as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer
thread will happily end up calling cifs_delete_mid while the
demultiplexer thread still is using the mid object.

Inserting a delay in the cifs demultiplexer thread widens the race
window and makes reproduction of the race very easy:

		if (server->large_buf)
			buf = server->bigbuf;

+		usleep_range(500, 4000);

		server->lstrp = jiffies;

To resolve this I think the proper solution involves putting a
reference count on the mid object. This patch makes sure that the
demultiplexer thread holds a reference until it has finished
processing the transaction.

Cc: stable@vger.kernel.org
Signed-off-by: Lars Persson <larper@axis.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-07-05 13:48:24 -05:00
Paulo Alcantara 35e2cc1ba7 cifs: Use correct packet length in SMB2_TRANSFORM header
In smb3_init_transform_rq(), 'orig_len' was only counting the request
length, but forgot to count any data pages in the request.

Writing or creating files with the 'seal' mount option was broken.

In addition, do some code refactoring by exporting smb2_rqst_len() to
calculate the appropriate packet size and avoid duplicating the same
calculation all over the code.

The start of the io vector is either the rfc1002 length (4 bytes) or a
SMB2 header which is always > 4. Use this fact to check and skip the
rfc1002 length if requested.

Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15 19:17:40 -05:00
Steve French bea851b8ba smb3: Fix mode on mkdir on smb311 mounts
mkdir was not passing the mode on smb3.11 mounts with posix extensions

Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15 02:38:08 -05:00