a trivial patch that replaces all use of snprintf with scnprintf.
scnprintf() is generally seen as a safer function to use than
snprintf for many use cases.
In our case, there is no actual difference between the two since we never
look at the return value. Thus we did not have any of the bugs that
scnprintf protects against and the patch does nothing.
However, for people reading our code it will be a receipt that we
have done our due dilligence and checked our code for this type of bugs.
See the presentation "Making C Less Dangerous In The Linux Kernel"
at this years LCA
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The request buffers are freed right before copying the pointers.
Use the func args instead which are identical and still valid.
Simple reproducer (requires KASAN enabled) on a cifs mount:
echo foo > foo ; tail -f foo & rm foo
Cc: <stable@vger.kernel.org> # 4.20
Fixes: 179e44d49c ("smb3: add tracepoint for sending lease break responses to server")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Currently we log success once we send an async IO request to
the server. Instead we need to analyse a response and then log
success or failure for a particular command. Also fix argument
list for read logging.
Cc: <stable@vger.kernel.org> # 4.18
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If we don't receive a response we can't assume that the server
granted one credit. Assume zero credits in such cases.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The call to SMB2_queary_acl can allocate memory to pntsd and also
return a failure via a call to SMB2_query_acl (and then query_info).
This occurs when query_info allocates the structure and then in
query_info the call to smb2_validate_and_copy_iov fails. Currently the
failure just returns without kfree'ing pntsd hence causing a memory
leak.
Currently, *data is allocated if it's not already pointing to a buffer,
so it needs to be kfree'd only if was allocated in query_info, so the
fix adds an allocated flag to track this. Also set *dlen to zero on
an error just to be safe since *data is kfree'd.
Also set errno to -ENOMEM if the allocation of *data fails.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Dan Carpener <dan.carpenter@oracle.com>
This addresses some compile warnings that you can
see depending on configuration settings.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently for MTU requests we allocate maximum possible credits
in advance and then adjust them according to the request size.
While we were adjusting the number of credits belonging to the
server, we were skipping adjustment of credits belonging to the
request. This patch fixes it by setting request credits to
CreditCharge field value of SMB2 packet header.
Also ask 1 credit more for async read and write operations to
increase parallelism and match the behavior of other operations.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
SMB3.1.1 dialect has additional security (among other) features
and should be requested when mounting to modern servers so it
can be used if the server supports it.
Add SMB3.1.1 to the default list of dialects requested.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
After a successful failover in cifs_reconnect(), the smb2_reconnect()
function will make sure to reconnect every tcon to new target server.
For SMB2+.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes gcc '-Wunused-but-set-variable' warning:
fs/cifs/smb2pdu.c: In function 'smb311_posix_mkdir':
fs/cifs/smb2pdu.c:2040:26: warning:
variable 'server' set but not used [-Wunused-but-set-variable]
fs/cifs/smb2pdu.c: In function 'build_qfs_info_req':
fs/cifs/smb2pdu.c:4067:26: warning:
variable 'server' set but not used [-Wunused-but-set-variable]
The first 'server' never used since commit bea851b8ba ("smb3: Fix mode on
mkdir on smb311 mounts")
And the second not used since commit 1fc6ad2f10 ("cifs: remove
header_preamble_size where it is always 0")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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>
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>
Change these free functions to allow passing NULL as the argument and
treat it as a no-op just like free(NULL) would.
Or, if rqst->rq_iov is NULL.
The second scenario could happen for smb2_queryfs() if the call
to SMB2_query_info_init() fails and we go to qfs_exit to clean up
and free all resources.
In that case we have not yet assigned rqst[2].rq_iov and thus
the rq_iov dereference in SMB2_close_free() will cause a NULL pointer
dereference.
Fixes: 1eb9fb5204 ("cifs: create SMB2_open_init()/SMB2_open_free() helpers")
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
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>
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>
In some error conditions, resp_buftype can be passed uninitialised to
free_rsp_buf(), potentially resulting in a spurious debug message.
If resp_buftype randomly had the value 1 (CIFS_SMALL_BUFFER) then this
would log a debug message.
The rsp pointer is initialised to NULL so there is no other side-effect.
Detected by CoverityScan, CID 1438585 ("Uninitialized scalar variable")
Detected by CoverityScan, CID 1438667 ("Uninitialized scalar variable")
Detected by CoverityScan, CID 1438764 ("Uninitialized scalar variable")
Signed-off-by: Garry McNulty <garrmcnu@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Be able to log a ftrace message on success and/or failure of
sending a lease break response to the server.
Example output:
TASK-PID CPU# |||| TIMESTAMP FUNCTION
| | | |||| | |
kworker/1:1-5681 [001] .... 11123.530457: smb3_lease_done: sid=0x291e3e0f tid=0x8ba43071 lease_key=0x1852ca0d3ecd9b55847750a86716fde lease_state=0x0
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Get rid of smb2_open_op_close() as all operations are now migrated
to smb2_compound_op().
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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>
Cuts number of network roundtrips significantly for some common syscalls
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This and previous patches drop the number of roundtrips we need for rmdir()
from 6 to 2.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
so that we can use these later for compounded set-info calls.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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>
Use kmemdup rather than duplicating its implementation
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The "le32_to_cpu(rsp->OutputOffset) + *plen" addition can overflow and
wrap around to a smaller value which looks like it would lead to an
information leak.
Fixes: 4a72dafa19 ("SMB2 FSCTL and IOCTL worker function")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
The problem is that "entryptr + next_offset" and "entryptr + len + size"
can wrap. I ended up changing the type of "entryptr" because it makes
the math easier when we don't have to do so much casting.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
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>
mounting with the "snapshots=" mount parm allows a read-only
view of a previous version of a file system (see MS-SMB2
and "timewarp" tokens, section 2.2.13.2.6) based on the timestamp
passed in on the snapshots mount parm.
Add processing to optionally send this create context.
Example output:
/mnt1 is mounted with "snapshots=..." and will see an earlier
version of the directory, with three fewer files than /mnt2
the current version of the directory.
root@Ubuntu-17-Virtual-Machine:~/cifs-2.6# cat /proc/mounts | grep cifs
//172.22.149.186/public /mnt1 cifs
ro,relatime,vers=default,cache=strict,username=smfrench,uid=0,noforceuid,gid=0,noforcegid,addr=172.22.149.186,file_mode=0755,dir_mode=0755,soft,nounix,mapposix,rsize=1048576,wsize=1048576,echo_interval=60,snapshot=131748608570000000,actimeo=1
//172.22.149.186/public /mnt2 cifs
rw,relatime,vers=default,cache=strict,username=smfrench,uid=0,noforceuid,gid=0,noforcegid,addr=172.22.149.186,file_mode=0755,dir_mode=0755,soft,nounix,mapposix,rsize=1048576,wsize=1048576,echo_interval=60,actimeo=1
root@Ubuntu-17-Virtual-Machine:~/cifs-2.6# ls /mnt1
EmptyDir newerdir
root@Ubuntu-17-Virtual-Machine:~/cifs-2.6# ls /mnt1/newerdir
root@Ubuntu-17-Virtual-Machine:~/cifs-2.6# ls /mnt2
EmptyDir file newerdir newestdir timestamp-trace.cap
root@Ubuntu-17-Virtual-Machine:~/cifs-2.6# ls /mnt2/newerdir
new-file-not-in-snapshot
Snapshots are extremely useful for comparing previous versions of files or directories,
and recovering from data corruptions or mistakes.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
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>
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>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
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>
For SMB2/SMB3 the number of requests sent was not displayed
in /proc/fs/cifs/Stats unless CONFIG_CIFS_STATS2 was
enabled (only number of failed requests displayed). As
with earlier dialects, we should be displaying these
counters if CONFIG_CIFS_STATS is enabled. They
are important for debugging.
e.g. when you cat /proc/fs/cifs/Stats (before the patch)
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: 690 maximum at one time: 2
1) \\localhost\test
SMBs: 975
Negotiates: 0 sent 0 failed
SessionSetups: 0 sent 0 failed
Logoffs: 0 sent 0 failed
TreeConnects: 0 sent 0 failed
TreeDisconnects: 0 sent 0 failed
Creates: 0 sent 2 failed
Closes: 0 sent 0 failed
Flushes: 0 sent 0 failed
Reads: 0 sent 0 failed
Writes: 0 sent 0 failed
Locks: 0 sent 0 failed
IOCTLs: 0 sent 1 failed
Cancels: 0 sent 0 failed
Echos: 0 sent 0 failed
QueryDirectories: 0 sent 63 failed
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
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>
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>
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>
also fixes error code in smb311_posix_mkdir() (where
the error assignment needs to go before the goto)
a typo that Dan Carpenter and Paulo and Gustavo
pointed out.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.
So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.
Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().
Here's an example of how to trigger that:
$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard
(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 0.0 0.0 12892 1008 pts/0 S 12:24 0:00 stat -f
/mnt/test
$ kill -9 2511
(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 83.2 0.0 12892 1008 pts/0 R 12:24 30:01 stat -f
/mnt/test
By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Now that we have the plumbing to pass request without an rfc1002
header all the way down to the point we write to the socket we no
longer need the smb2_send_recv() function.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Move the generation of the 4 byte length field down the stack and
generate it immediately before we start writing the data to the socket.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Compared to other clients the Linux smb3 client ramps up
credits very slowly, taking more than 128 operations before a
maximum size write could be sent (since the number of credits
requested is only 2 per small operation, causing the credit
limit to grow very slowly).
This lack of credits initially would impact large i/o performance,
when large i/o is tried early before enough credits are built up.
Signed-off-by: Steve French <stfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
