Make sure that we do not share tcp sessions of dfs mounts when
mounting regular shares that connect to same server. DFS connections
rely on a single instance of tcp in order to do failover properly in
cifs_reconnect().
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
We recently fixed DNS resolution of the server hostname during reconnect.
However, server IP address may change, even when the old one continues
to server (although sub-optimally).
We should schedule the next DNS resolution based on the TTL of
the DNS record used for the last resolution. This way, we resolve the
server hostname again when a DNS record expires.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: Steve French <stfrench@microsoft.com>
Support for faster packet signing (using GMAC instead of CMAC) can
now be negotiated to some newer servers, including Windows.
See MS-SMB2 section 2.2.3.17.
This patch adds support for sending the new negotiate context
with the first of three supported signing algorithms (AES-CMAC)
and decoding the response. A followon patch will add support
for sending the other two (including AES-GMAC, which is fastest)
and changing the signing algorithm used based on what was
negotiated.
To allow the client to request GMAC signing set module parameter
"enable_negotiate_signing" to 1.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
There were three places where we were not taking the spinlock
around updates to server->tcpStatus when it was being modified.
To be consistent (also removes Coverity warning) and to remove
possibility of race best to lock all places where it is updated.
Two of the three were in initialization of the field and can't
race - but added lock around the other.
Addresses-Coverity: 1399512 ("Data race condition")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
There was one place where we weren't locking CurrentMid, and although
likely to be safe since even without the lock since it is during
negotiate protocol, it is more consistent to lock it in this last remaining
place, and avoids confusing Coverity warning.
Addresses-Coverity: 1486665 ("Data race condition")
Signed-off-by: Steve French <stfrench@microsoft.com>
In the other places where we update ses->status we protect the
updates via GlobalMid_Lock. So to be consistent add the same
locking around it in cifs_put_smb_ses where it was missing.
Addresses-Coverity: 1268904 ("Data race condition")
Signed-off-by: Steve French <stfrench@microsoft.com>
Add SPDX license identifier and replace license boilerplate.
Corrects various checkpatch errors with the older format for
noting the LGPL license.
Signed-off-by: Steve French <stfrench@microsoft.com>
Convert all dfs paths to dfs cache's local codepage (@cache_cp) and
avoid mixing them with different charsets.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When smb2 lease parameter is disabled on server. Server grants
batch oplock instead of RHW lease by default on open, inode page cache
needs to be zapped immediatley upon close as cache is not valid.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Removed oplock_break_received flag which was added to achieve
synchronization between oplock handler and open handler by earlier commit.
It is not needed because there is an existing lock open_file_lock to achieve
the same. find_readable_file takes open_file_lock and then traverses the
openFileList. Similarly, cifs_oplock_break while closing the deferred
handle (i.e cifsFileInfo_put) takes open_file_lock and then sends close
to the server.
Added comments for better readability.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When file is closed, SMB2 close request is not sent to server
immediately and is deferred for acregmax defined interval. When file is
reopened by same process for read or write, the file handle
is reused if an oplock is held.
When client receives a oplock/lease break, file is closed immediately
if reference count is zero, else oplock is downgraded.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
and clear the timestamp when we receive a lease break.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We need to hold both a reference for the root/superblock as well as the directory that we
are caching. We need to drop these references before we call kill_anon_sb().
At this point, the root and the cached dentries are always the same but this will change
once we start caching other directories as well.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
While reviewing a patch clarifying locks and locking hierarchy I
realized some locks were unused.
This commit removes old data and code that isn't actually used
anywhere, or hidden in ifdefs which cannot be enabled from the kernel
config.
* The uid/gid trees and associated locks are left-overs from when
uid/sid mapping had an extra caching layer on top of the keyring and
are now unused.
See commit faa65f07d2 ("cifs: simplify id_to_sid and sid_to_id mapping code")
from 2012.
* cifs_oplock_break_ops is a left-over from when slow_work was remplaced
by regular workqueue and is now unused.
See commit 9b64697246 ("cifs: use workqueue instead of slow-work")
from 2010.
* CIFSSMBSetAttrLegacy is SMB1 cruft dealing with some legacy
NT4/Win9x behaviour.
* Remove CONFIG_CIFS_DNOTIFY_EXPERIMENTAL left-overs. This was already
partially removed in 392e1c5dc9 ("cifs: rename and clarify CIFS_ASYNC_OP and CIFS_NO_RESP")
from 2019. Kill it completely.
* Another candidate that was considered but spared is
CONFIG_CIFS_NFSD_EXPORT which has an empty implementation and cannot
be enabled by a config option (although it is listed but disabled with
"BROKEN" as a dep). It's unclear whether this could even function
today in its current form but it has it's own .c file and Kconfig
entry which is a bit more involved to remove and might make a come
back?
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
struct cifs_writedata is declared twice.
One is declared at 209th line.
And struct cifs_writedata is defined blew.
The declaration hear is not needed. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit doesn't change the logic of SWN.
Add dummy implementation of SWN functions when SWN is disabled instead
of using ifdef sections.
The dummy functions get optimized out, this leads to clearer code and
compile time type-checking regardless of config options with no
runtime penalty.
Leave the simple ifdefs section as-is.
A single bitfield (bool foo:1) on its own will use up one int. Move
tcon->use_witness out of ifdefs with the other tcon bitfields.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Samuel Cabrero <scabrero@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
A few of the semaphores had been removed, and one additional one
needed to be noted in the comments.
Signed-off-by: Steve French <stfrench@microsoft.com>
struct cifs_readdata is declared twice. One is declared
at 208th line.
And struct cifs_readdata is defined blew.
The declaration here is not needed. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For AES256 encryption (GCM and CCM), we need to adjust the size of a few
fields to 32 bytes instead of 16 to accommodate the larger keys.
Also, the L value supplied to the key generator needs to be changed from
to 256 when these algorithms are used.
Keeping the ioctl struct for dumping keys of the same size for now.
Will send out a different patch for that one.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Steve French <stfrench@microsoft.com>
In case of interrupted syscalls, prevent sending CLOSE commands for
compound CREATE+CLOSE requests by introducing an
CIFS_CP_CREATE_CLOSE_OP flag to indicate lower layers that it should
not send a CLOSE command to the MIDs corresponding the compound
CREATE+CLOSE request.
A simple reproducer:
#!/bin/bash
mount //server/share /mnt -o username=foo,password=***
tc qdisc add dev eth0 root netem delay 450ms
stat -f /mnt &>/dev/null & pid=$!
sleep 0.01
kill $pid
tc qdisc del dev eth0 root
umount /mnt
Before patch:
...
6 0.256893470 192.168.122.2 → 192.168.122.15 SMB2 402 Create Request File: ;GetInfo Request FS_INFO/FileFsFullSizeInformation;Close Request
7 0.257144491 192.168.122.15 → 192.168.122.2 SMB2 498 Create Response File: ;GetInfo Response;Close Response
9 0.260798209 192.168.122.2 → 192.168.122.15 SMB2 146 Close Request File:
10 0.260841089 192.168.122.15 → 192.168.122.2 SMB2 130 Close Response, Error: STATUS_FILE_CLOSED
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
When server returns error STATUS_NETWORK_NAME_DELETED, TCON
must be marked for reconnect. So, subsequent IO does the tree
connect again.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
ses->serverName is not the server name, but the string form
of the ip address of the server. Change the name to ip_addr
to avoid confusion (and fix the array length to match
maximum length of ipv6 address).
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Introduced a new field conn_id in TCP_Server_Info structure.
This is a non-persistent unique identifier maintained by the client
for a connection to a file server. For this, a global counter named
tcpSesNextId is maintained. On allocating a new TCP_Server_Info,
this counter is incremented and assigned.
Changed the dynamic tracepoints related to reconnects and
crediting to be more informative (with conn_id printed).
Debugging a crediting issue helped me understand the
important things to print here.
Always call dynamic tracepoints outside the scope of spinlocks.
To do this, copy out the credits and in_flight fields of the
server struct before dropping the lock.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We used to share the CIFS_NEG_OP flag between negotiate and
session authentication. There was an assumption in the code that
CIFS_NEG_OP is used by negotiate only. So introcuded CIFS_SESS_OP
and used it for session setup optypes.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add SYSTEM_SECURITY access flag and use with smb2 when opening
files for getting/setting SACLs. Add "system.cifs_ntsd_full"
extended attribute to allow user-space access to the functionality.
Avoid multiple server calls when setting owner, DACL, and SACL.
Signed-off-by: Boris Protopopov <pboris@amazon.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This message is sent to tell a client to close its current connection
and connect to the specified address.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add 'witness' mount option to register for witness notifications.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Harmonize and change all such variables to 'ctx', where possible.
No changes to actual logic.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This and related patches which move mount related
code to fs_context.c has the advantage of
shriking the code in fs/cifs/connect.c (which had
the second most lines of code of any of the files
in cifs.ko and was getting harder to read due
to its size) and will also make it easier to
switch over to the new mount API in the future.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add new module load parameter enable_gcm_256. If set, then add
AES-256-GCM (strongest encryption type) to the list of encryption
types requested. Put it in the list as the second choice (since
AES-128-GCM is faster and much more broadly supported by
SMB3 servers). To make this stronger encryption type, GCM-256,
required (the first and only choice, you would use module parameter
"require_gcm_256."
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add new module load parameter require_gcm_256. If set, then only
request AES-256-GCM (strongest encryption type).
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently STATUS_IO_TIMEOUT is not treated as retriable error.
It is currently mapped to ETIMEDOUT and returned to userspace
for most system calls. STATUS_IO_TIMEOUT is returned by server
in case of unavailability or throttling errors.
This patch will map the STATUS_IO_TIMEOUT to EAGAIN, so that it
can be retried. Also, added a check to drop the connection to
not overload the server in case of ongoing unavailability.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For SMB1, the DFS flag should be checked against tcon->Flags rather
than tcon->share_flags. While at it, add an is_tcon_dfs() helper to
check for DFS capability in a more generic way.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
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Merge tag '5.9-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs updates from Steve French:
"16 cifs/smb3 fixes, about half DFS related, two fixes for stable.
Still working on and testing an additional set of fixes (including
updates to mount, and some fallocate scenario improvements) for later
in the merge window"
* tag '5.9-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6:
cifs: document and cleanup dfs mount
cifs: only update prefix path of DFS links in cifs_tree_connect()
cifs: fix double free error on share and prefix
cifs: handle RESP_GET_DFS_REFERRAL.PathConsumed in reconnect
cifs: handle empty list of targets in cifs_reconnect()
cifs: rename reconn_inval_dfs_target()
cifs: reduce number of referral requests in DFS link lookups
cifs: merge __{cifs,smb2}_reconnect[_tcon]() into cifs_tree_connect()
cifs: convert to use be32_add_cpu()
cifs: delete duplicated words in header files
cifs: Remove the superfluous break
cifs: smb1: Try failing back to SetFileInfo if SetPathInfo fails
cifs`: handle ERRBaduid for SMB1
cifs: remove unused variable 'server'
smb3: warn on confusing error scenario with sec=krb5
cifs: Fix leak when handling lease break for cached root fid
Drop repeated words in multiple comments.
(be, use, the, See)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Link: https://lore.kernel.org/r/20200627103125.71828-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This code is more organized and robust.
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add a cifs_chan pointer in struct cifs_ses that points to the channel
currently being bound if ses->binding is true.
Previously it was always the channel past the established count.
This will make reconnecting (and rebinding) a channel easier later on.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move the channel (TCP_Server_Info*) selection from the tranport
layer to higher in the call stack so that:
- credit handling is done with the server that will actually be used
to send.
* ->wait_mtu_credit
* ->set_credits / set_credits
* ->add_credits / add_credits
* add_credits_and_wake_if
- potential reconnection (smb2_reconnect) done when initializing a
request is checked and done with the server that will actually be
used to send.
To do this:
- remove the cifs_pick_channel() call out of compound_send_recv()
- select channel and pass it down by adding a cifs_pick_channel(ses)
call in:
- smb311_posix_mkdir
- SMB2_open
- SMB2_ioctl
- __SMB2_close
- query_info
- SMB2_change_notify
- SMB2_flush
- smb2_async_readv (if none provided in context param)
- SMB2_read (if none provided in context param)
- smb2_async_writev (if none provided in context param)
- SMB2_write (if none provided in context param)
- SMB2_query_directory
- send_set_info
- SMB2_oplock_break
- SMB311_posix_qfs_info
- SMB2_QFS_info
- SMB2_QFS_attr
- smb2_lockv
- SMB2_lease_break
- smb2_compound_op
- smb2_set_ea
- smb2_ioctl_query_info
- smb2_query_dir_first
- smb2_query_info_comound
- smb2_query_symlink
- cifs_writepages
- cifs_write_from_iter
- cifs_send_async_read
- cifs_read
- cifs_readpages
- add TCP_Server_Info *server param argument to:
- cifs_send_recv
- compound_send_recv
- SMB2_open_init
- SMB2_query_info_init
- SMB2_set_info_init
- SMB2_close_init
- SMB2_ioctl_init
- smb2_iotcl_req_init
- SMB2_query_directory_init
- SMB2_notify_init
- SMB2_flush_init
- build_qfs_info_req
- smb2_hdr_assemble
- smb2_reconnect
- fill_small_buf
- smb2_plain_req_init
- __smb2_plain_req_init
The read/write codepath is different than the rest as it is using
pages, io iterators and async calls. To deal with those we add a
server pointer in the cifs_writedata/cifs_readdata/cifs_io_parms
context struct and set it in:
- cifs_writepages (wdata)
- cifs_write_from_iter (wdata)
- cifs_readpages (rdata)
- cifs_send_async_read (rdata)
The [rw]data->server pointer is eventually copied to
cifs_io_parms->server to pass it down to SMB2_read/SMB2_write.
If SMB2_read/SMB2_write is called from a different place that doesn't
set the server field it will pick a channel.
Some places do not pick a channel and just use ses->server or
cifs_ses_server(ses). All cifs_ses_server(ses) calls are in codepaths
involving negprot/sess.setup.
- SMB2_negotiate (binding channel)
- SMB2_sess_alloc_buffer (binding channel)
- SMB2_echo (uses provided one)
- SMB2_logoff (uses master)
- SMB2_tdis (uses master)
(list not exhaustive)
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to handle workloads where it is important to make sure that
a buggy app did not delete content on the drive, the new mount option
"nodelete" allows standard permission checks on the server to work,
but prevents on the client any attempts to unlink a file or delete
a directory on that mount point. This can be helpful when running
a little understood app on a network mount that contains important
content that should not be deleted.
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Add experimental support for allowing a swap file to be on an SMB3
mount. There are use cases where swapping over a secure network
filesystem is preferable. In some cases there are no local
block devices large enough, and network block devices can be
hard to setup and secure. And in some cases there are no
local block devices at all (e.g. with the recent addition of
remote boot over SMB3 mounts).
There are various enhancements that can be added later e.g.:
- doing a mandatory byte range lock over the swapfile (until
the Linux VFS is modified to notify the file system that an open
is for a swapfile, when the file can be opened "DENY_ALL" to prevent
others from opening it).
- pinning more buffers in the underlying transport to minimize memory
allocations in the TCP stack under the fs
- documenting how to create ACLs (on the server) to secure the
swapfile (or adding additional tools to cifs-utils to make it easier)
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CIFS uses pre-allocated crypto structures to calculate signatures for both
incoming and outgoing packets. In this way it doesn't need to allocate crypto
structures for every packet, but it requires a lock to prevent concurrent
access to crypto structures.
Remove the lock by allocating crypto structures on the fly for
incoming packets. At the same time, we can still use pre-allocated crypto
structures for outgoing packets, as they are already protected by transport
lock srv_mutex.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
To rename a file in SMB2 we open it with the DELETE access and do a
special SetInfo on it. If the handle is missing the DELETE bit the
server will fail the SetInfo with STATUS_ACCESS_DENIED.
We currently try to reuse any existing opened handle we have with
cifs_get_writable_path(). That function looks for handles with WRITE
access but doesn't check for DELETE, making rename() fail if it finds
a handle to reuse. Simple reproducer below.
To select handles with the DELETE bit, this patch adds a flag argument
to cifs_get_writable_path() and find_writable_file() and the existing
'bool fsuid_only' argument is converted to a flag.
The cifsFileInfo struct only stores the UNIX open mode but not the
original SMB access flags. Since the DELETE bit is not mapped in that
mode, this patch stores the access mask in cifs_fid on file open,
which is accessible from cifsFileInfo.
Simple reproducer:
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define E(s) perror(s), exit(1)
int main(int argc, char *argv[])
{
int fd, ret;
if (argc != 3) {
fprintf(stderr, "Usage: %s A B\n"
"create&open A in write mode, "
"rename A to B, close A\n", argv[0]);
return 0;
}
fd = openat(AT_FDCWD, argv[1], O_WRONLY|O_CREAT|O_SYNC, 0666);
if (fd == -1) E("openat()");
ret = rename(argv[1], argv[2]);
if (ret) E("rename()");
ret = close(fd);
if (ret) E("close()");
return ret;
}
$ gcc -o bugrename bugrename.c
$ ./bugrename /mnt/a /mnt/b
rename(): Permission denied
Fixes: 8de9e86c67 ("cifs: create a helper to find a writeable handle by path name")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
A commonly used SMB3 feature is change notification, allowing an
app to be notified about changes to a directory. The SMB3
Notify request blocks until the server detects a change to that
directory or its contents that matches the completion flags
that were passed in and the "watch_tree" flag (which indicates
whether subdirectories under this directory should be also
included). See MS-SMB2 2.2.35 for additional detail.
To use this simply pass in the following structure to ioctl:
struct __attribute__((__packed__)) smb3_notify {
uint32_t completion_filter;
bool watch_tree;
} __packed;
using CIFS_IOC_NOTIFY 0x4005cf09
or equivalently _IOW(CIFS_IOCTL_MAGIC, 9, struct smb3_notify)
SMB3 change notification is supported by all major servers.
The ioctl will block until the server detects a change to that
directory or its subdirectories (if watch_tree is set).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag was missing from
some of the operations.
Change all operations to use the macro cifs_create_options() to
set the backup intent flag if needed.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When listing a directory with thounsands of files and most of them are
reparse points, we simply marked all those dentries for revalidation
and then sending additional (compounded) create/getinfo/close requests
for each of them.
Instead, upon receiving a response from an SMB2_QUERY_DIRECTORY
(FileIdFullDirectoryInformation) command, the directory entries that
have a file attribute of FILE_ATTRIBUTE_REPARSE_POINT will contain an
EaSize field with a reparse tag in it, so we parse it and mark the
dentry for revalidation only if it is a DFS or a symlink.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
