Commit Graph

3609 Commits

Author SHA1 Message Date
Steve French
adbb2dafe7 cifs: minor fix to two debug messages
Joe Perches pointed out that we were missing a newline
at the end of two debug messages

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Joe Perches
a0a3036b81 cifs: Standardize logging output
Use pr_fmt to standardize all logging for fs/cifs.

Some logging output had no CIFS: specific prefix.

Now all output has one of three prefixes:

o CIFS:
o CIFS: VFS:
o Root-CIFS:

Miscellanea:

o Convert printks to pr_<level>
o Neaten macro definitions
o Remove embedded CIFS: prefixes from formats
o Convert "illegal" to "invalid"
o Coalesce formats
o Add missing '\n' format terminations
o Consolidate multiple cifs_dbg continuations into single calls
o More consistent use of upper case first word output logging
o Multiline statement argument alignment and wrapping

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Steve French
82e9367c43 smb3: Add new parm "nodelete"
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>
2020-06-01 00:10:18 -05:00
Ronnie Sahlberg
b2ca6c2c9e cifs: move some variables off the stack in smb2_ioctl_query_info
Move some large data structures off the stack and into dynamically
allocated memory in the function smb2_ioctl_query_info

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Ronnie Sahlberg
a7d5c29462 cifs: reduce stack use in smb2_compound_op
Move a lot of structures and arrays off the stack and into a dynamically
allocated structure instead.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Paulo Alcantara
baf3f08ef4 cifs: get rid of unused parameter in reconn_setup_dfs_targets()
The target iterator parameter "it" is not used in
reconn_setup_dfs_targets(), so just remove it.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Paulo Alcantara
e4af35fa55 cifs: handle hostnames that resolve to same ip in failover
In order to support reconnect to hostnames that resolve to same ip
address, besides relying on the currently set hostname to match DFS
targets, attempt to resolve the targets and then match their addresses
with the reconnected server ip address.

For instance, if we have two hostnames "FOO" and "BAR", and both
resolve to the same ip address, we would be able to handle failover in
DFS paths like

    \\FOO\dfs\link1 -> [ \BAZ\share2 (*), \BAR\share1 ]
    \\FOO\dfs\link2 -> [ \BAZ\share2 (*), \FOO\share1 ]

so when "BAZ" is no longer accessible, link1 and link2 would get
reconnected despite having different target hostnames.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Paulo Alcantara
aaa3aef34d cifs: set up next DFS target before generic_ip_connect()
If we mount a very specific DFS link

    \\FS0.FOO.COM\dfs\link -> \FS0\share1, \FS1\share2

where its target list contains NB names ("FS0" & "FS1") rather than
FQDN ones ("FS0.FOO.COM" & "FS1.FOO.COM"), we end up connecting to
\FOO\share1 but server->hostname will have "FOO.COM".  The reason is
because both "FS0" and "FS0.FOO.COM" resolve to same IP address and
they share same TCP server connection, but "FS0.FOO.COM" was the first
hostname set -- which is OK.

However, if the echo thread timeouts and we still have a good
connection to "FS0", in cifs_reconnect()

    rc = generic_ip_connect(server) -> success
    if (rc) {
            ...
            reconn_inval_dfs_target(server, cifs_sb, &tgt_list,
	                            &tgt_it);
            ...
     }
     ...

it successfully reconnects to "FS0" server but does not set up next
DFS target - which should be the same target server "\FS0\share1" -
and server->hostname remains set to "FS0.FOO.COM" rather than "FS0",
as reconn_inval_dfs_target() would have it set to "FS0" if called
earlier.

Finally, in __smb2_reconnect(), the reconnect of tcons would fail
because tcon->ses->server->hostname (FS0.FOO.COM) does not match DFS
target's hostname (FS0).

Fix that by calling reconn_inval_dfs_target() before
generic_ip_connect() so server->hostname will get updated correctly
prior to reconnecting its tcons in __smb2_reconnect().

With "cifs: handle hostnames that resolve to same ip in failover"
patch

    - The above problem would not occur.
    - We could save an DNS query to find out that they both resolve to
      the same ip address.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Colin Ian King
136a5dc330 cifs: remove redundant initialization of variable rc
The variable rc is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Kenneth D'souza
8fd6e1d694 cifs: handle "nolease" option for vers=1.0
The "nolease" mount option is only supported for SMB2+ mounts.
Fail with appropriate error message if vers=1.0 option is passed.

Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:17 -05:00
Christoph Hellwig
12abc5ee78 tcp: add tcp_sock_set_nodelay
Add a helper to directly set the TCP_NODELAY sockopt from kernel space
without going through a fake uaccess.  Cleanup the callers to avoid
pointless wrappers now that this is a simple function call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:45 -07:00
Christoph Hellwig
db10538a4b tcp: add tcp_sock_set_cork
Add a helper to directly set the TCP_CORK sockopt from kernel space
without going through a fake uaccess.  Cleanup the callers to avoid
pointless wrappers now that this is a simple function call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:45 -07:00
Adam McCoy
a481379960 cifs: fix leaked reference on requeued write
Failed async writes that are requeued may not clean up a refcount
on the file, which can result in a leaked open. This scenario arises
very reliably when using persistent handles and a reconnect occurs
while writing.

cifs_writev_requeue only releases the reference if the write fails
(rc != 0). The server->ops->async_writev operation will take its own
reference, so the initial reference can always be released.

Signed-off-by: Adam McCoy <adam@forsedomani.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-05-14 17:47:01 -05:00
Steve French
9bd21d4b1a cifs: Fix null pointer check in cifs_read
Coverity scan noted a redundant null check

Coverity-id: 728517
Reported-by: Coverity <scan-admin@coverity.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
2020-05-14 10:30:03 -05:00
Geert Uytterhoeven
3dc58df0e2 CIFS: Spelling s/EACCESS/EACCES/
As per POSIX, the correct spelling is EACCES:

include/uapi/asm-generic/errno-base.h:#define EACCES 13 /* Permission denied */

Fixes: b8f7442bc4 ("CIFS: refactor cifs_get_inode_info()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-05-06 10:21:40 -05:00
Paulo Alcantara
0fe0781f29 cifs: fix uninitialised lease_key in open_shroot()
SMB2_open_init() expects a pre-initialised lease_key when opening a
file with a lease, so set pfid->lease_key prior to calling it in
open_shroot().

This issue was observed when performing some DFS failover tests and
the lease key was never randomly generated.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2020-04-22 20:29:11 -05:00
Paulo Alcantara
3786f4bddc cifs: ensure correct super block for DFS reconnect
This patch is basically fixing the lookup of tcons (DFS specific) during
reconnect (smb2pdu.c:__smb2_reconnect) to update their prefix paths.

Previously, we relied on the TCP_Server_Info pointer
(misc.c:tcp_super_cb) to determine which tcon to update the prefix path

We could not rely on TCP server pointer to determine which super block
to update the prefix path when reconnecting tcons since it might map
to different tcons that share same TCP connection.

Instead, walk through all cifs super blocks and compare their DFS full
paths with the tcon being updated to.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-04-22 20:27:30 -05:00
Paulo Alcantara
65303de829 cifs: do not share tcons with DFS
This disables tcon re-use for DFS shares.

tcon->dfs_path stores the path that the tcon should connect to when
doing failing over.

If that tcon is used multiple times e.g. 2 mounts using it with
different prefixpath, each will need a different dfs_path but there is
only one tcon. The other solution would be to split the tcon in 2
tcons during failover but that is much harder.

tcons could not be shared with DFS in cifs.ko because in a
DFS namespace like:

          //domain/dfsroot -> /serverA/dfsroot, /serverB/dfsroot

          //serverA/dfsroot/link -> /serverA/target1/aa/bb

          //serverA/dfsroot/link2 -> /serverA/target1/cc/dd

you can see that link and link2 are two DFS links that both resolve to
the same target share (/serverA/target1), so cifs.ko will only contain a
single tcon for both link and link2.

The problem with that is, if we (auto)mount "link" and "link2", cifs.ko
will only contain a single tcon for both DFS links so we couldn't
perform failover or refresh the DFS cache for both links because
tcon->dfs_path was set to either "link" or "link2", but not both --
which is wrong.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-22 20:22:08 -05:00
Steve French
d92c7ce41e cifs: minor update to comments around the cifs_tcp_ses_lock mutex
Update comment to note that it protects server->dstaddr

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-21 23:51:18 -05:00
Ronnie Sahlberg
fada37f6f6 cifs: protect updating server->dstaddr with a spinlock
We use a spinlock while we are reading and accessing the destination address for a server.
We need to also use this spinlock to protect when we are modifying this address from
reconn_set_ipaddr().

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-21 09:57:56 -05:00
Steve French
9692ea9d32 smb3: remove overly noisy debug line in signing errors
A dump_stack call for signature related errors can be too noisy
and not of much value in debugging such problems.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
2020-04-16 12:23:40 -05:00
Jones Syue
1f641d9410 cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
Found a read performance issue when linux kernel page size is 64KB.
If linux kernel page size is 64KB and mount options cache=strict &
vers=2.1+, it does not support cifs_readpages(). Instead, it is using
cifs_readpage() and cifs_read() with maximum read IO size 16KB, which is
much slower than read IO size 1MB when negotiated SMB 2.1+. Since modern
SMB server supported SMB 2.1+ and Max Read Size can reach more than 64KB
(for example 1MB ~ 8MB), this patch check max_read instead of maxBuf to
determine whether server support readpages() and improve read performance
for page size 64KB & cache=strict & vers=2.1+, and for SMB1 it is more
cleaner to initialize server->max_read to server->maxBuf.

The client is a linux box with linux kernel 4.2.8,
page size 64KB (CONFIG_ARM64_64K_PAGES=y),
cpu arm 1.7GHz, and use mount.cifs as smb client.
The server is another linux box with linux kernel 4.2.8,
share a file '10G.img' with size 10GB,
and use samba-4.7.12 as smb server.

The client mount a share from the server with different
cache options: cache=strict and cache=none,
mount -tcifs //<server_ip>/Public /cache_strict -overs=3.0,cache=strict,username=<xxx>,password=<yyy>
mount -tcifs //<server_ip>/Public /cache_none -overs=3.0,cache=none,username=<xxx>,password=<yyy>

The client download a 10GbE file from the server across 1GbE network,
dd if=/cache_strict/10G.img of=/dev/null bs=1M count=10240
dd if=/cache_none/10G.img of=/dev/null bs=1M count=10240

Found that cache=strict (without patch) is slower read throughput and
smaller read IO size than cache=none.
cache=strict (without patch): read throughput 40MB/s, read IO size is 16KB
cache=strict (with patch): read throughput 113MB/s, read IO size is 1MB
cache=none: read throughput 109MB/s, read IO size is 1MB

Looks like if page size is 64KB,
cifs_set_ops() would use cifs_addr_ops_smallbuf instead of cifs_addr_ops,

	/* check if server can support readpages */
	if (cifs_sb_master_tcon(cifs_sb)->ses->server->maxBuf <
			PAGE_SIZE + MAX_CIFS_HDR_SIZE)
		inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
	else
		inode->i_data.a_ops = &cifs_addr_ops;

maxBuf is came from 2 places, SMB2_negotiate() and CIFSSMBNegotiate(),
(SMB2_MAX_BUFFER_SIZE is 64KB)
SMB2_negotiate():
	/* set it to the maximum buffer size value we can send with 1 credit */
	server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize),
			       SMB2_MAX_BUFFER_SIZE);
CIFSSMBNegotiate():
	server->maxBuf = le32_to_cpu(pSMBr->MaxBufferSize);

Page size 64KB and cache=strict lead to read_pages() use cifs_readpage()
instead of cifs_readpages(), and then cifs_read() using maximum read IO
size 16KB, which is much slower than maximum read IO size 1MB.
(CIFSMaxBufSize is 16KB by default)

	/* FIXME: set up handlers for larger reads and/or convert to async */
	rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Jones Syue <jonessyue@qnap.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-15 21:15:11 -05:00
Ronnie Sahlberg
f560cda91b cifs: dump the session id and keys also for SMB2 sessions
We already dump these keys for SMB3, lets also dump it for SMB2
sessions so that we can use the session key in wireshark to check and validate
that the signatures are correct.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-04-15 21:15:03 -05:00
Steve French
4e8aea30f7 smb3: enable swap on SMB3 mounts
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>
2020-04-10 13:32:32 -05:00
Steve French
1dc94b7381 smb3: change noisy error message to FYI
The noisy posix error message in readdir was supposed
to be an FYI (not enabled by default)
  CIFS VFS: XXX dev 66306, reparse 0, mode 755

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-04-09 13:28:24 -05:00
Steve French
2bcb4fd6ba smb3: smbdirect support can be configured by default
smbdirect support (SMB3 over RDMA) should be enabled by
default in many configurations.

It is not experimental and is stable enough and has enough
performance benefits to recommend that it be configured by
default.  Change the  "If unsure N" to "If unsure Y" in
the description of the configuration parameter.

Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 13:39:00 -05:00
Long Li
044b541c11 cifs: smbd: Do not schedule work to send immediate packet on every receive
Immediate packets should only be sent to peer when there are new
receive credits made available. New credits show up on freeing
receive buffer, not on receiving data.

Fix this by avoid unnenecessary work schedules.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 12:41:16 -05:00
Long Li
f1b7b862bf cifs: smbd: Properly process errors on ib_post_send
When processing errors from ib_post_send(), the transport state needs to be
rolled back to the condition before the error.

Refactor the old code to make it easy to roll back on IB errors, and fix this.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 12:41:16 -05:00
Long Li
eda1c54f14 cifs: Allocate crypto structures on the fly for calculating signatures of incoming packets
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>
2020-04-07 12:41:16 -05:00
Long Li
d4e5160d1a cifs: smbd: Update receive credits before sending and deal with credits roll back on failure before sending
Recevie credits should be updated before sending the packet, not
before a work is scheduled. Also, the value needs roll back if
something fails and cannot send.

Signed-off-by: Long Li <longli@microsoft.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 12:41:16 -05:00
Long Li
3ffbe78aff cifs: smbd: Check send queue size before posting a send
Sometimes the remote peer may return more send credits than the send queue
depth. If all the send credits are used to post senasd, we may overflow the
send queue.

Fix this by checking the send queue size before posting a send.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 12:41:16 -05:00
Long Li
072a14ec63 cifs: smbd: Merge code to track pending packets
As an optimization, SMBD tries to track two types of packets: packets with
payload and without payload. There is no obvious benefit or performance gain
to separately track two types of packets.

Just treat them as pending packets and merge the tracking code.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-07 12:41:16 -05:00
Aurelien Aptel
e79b0332ae cifs: ignore cached share root handle closing errors
Fix tcon use-after-free and NULL ptr deref.

Customer system crashes with the following kernel log:

[462233.169868] CIFS VFS: Cancelling wait for mid 4894753 cmd: 14       => a QUERY DIR
[462233.228045] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.305922] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.306205] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347060] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347107] CIFS VFS: Close unmatched open
[462233.347113] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
...
    [exception RIP: cifs_put_tcon+0xa0] (this is doing tcon->ses->server)
 #6 [...] smb2_cancelled_close_fid at ... [cifs]
 #7 [...] process_one_work at ...
 #8 [...] worker_thread at ...
 #9 [...] kthread at ...

The most likely explanation we have is:

* When we put the last reference of a tcon (refcount=0), we close the
  cached share root handle.
* If closing a handle is interrupted, SMB2_close() will
  queue a SMB2_close() in a work thread.
* The queued object keeps a tcon ref so we bump the tcon
  refcount, jumping from 0 to 1.
* We reach the end of cifs_put_tcon(), we free the tcon object despite
  it now having a refcount of 1.
* The queued work now runs, but the tcon, ses & server was freed in
  the meantime resulting in a crash.

THREAD 1
========
cifs_put_tcon                 => tcon refcount reach 0
  SMB2_tdis
   close_shroot_lease
    close_shroot_lease_locked => if cached root has lease && refcount = 0
     smb2_close_cached_fid    => if cached root valid
      SMB2_close              => retry close in a thread if interrupted
       smb2_handle_cancelled_close
        __smb2_handle_cancelled_close    => !! tcon refcount bump 0 => 1 !!
         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
         queue_work(cifsiod_wq, &cancelled->work) => queue work
 tconInfoFree(tcon);    ==> freed!
 cifs_put_smb_ses(ses); ==> freed!

THREAD 2 (workqueue)
========
smb2_cancelled_close_fid
  SMB2_close(0, cancelled->tcon, ...); => use-after-free of tcon
  cifs_put_tcon(cancelled->tcon);      => tcon refcount reach 0 second time
  *CRASH*

Fixes: d919131935 ("CIFS: Close cached root handle only if it has a lease")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-04-07 12:40:40 -05:00
Steve French
f460c50274 cifs: update internal module version number
To 2.26

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-29 16:59:31 -05:00
Long Li
3946d0d04b cifs: Allocate encryption header through kmalloc
When encryption is used, smb2_transform_hdr is defined on the stack and is
passed to the transport. This doesn't work with RDMA as the buffer needs to
be DMA'ed.

Fix it by using kmalloc.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-29 16:42:54 -05:00
Long Li
4ebb8795a7 cifs: smbd: Check and extend sender credits in interrupt context
When a RDMA packet is received and server is extending send credits, we should
check and unblock senders immediately in IRQ context. Doing it in a worker
queue causes unnecessary delay and doesn't save much CPU on the receive path.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-29 16:42:36 -05:00
Long Li
f7950cb05d cifs: smbd: Calculate the correct maximum packet size for segmented SMBDirect send/receive
The packet size needs to take account of SMB2 header size and possible
encryption header size. This is only done when signing is used and it is for
RDMA send/receive, not read/write.

Also remove the dead SMBD code in smb2_negotiate_r(w)size.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-29 16:41:49 -05:00
Steve French
edad734c74 smb3: use SMB2_SIGNATURE_SIZE define
It clarifies the code slightly to use SMB2_SIGNATURE_SIZE
define rather than 16.

Suggested-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-27 12:47:41 -05:00
Yilu Lin
97adda8b3a CIFS: Fix bug which the return value by asynchronous read is error
This patch is used to fix the bug in collect_uncached_read_data()
that rc is automatically converted from a signed number to an
unsigned number when the CIFS asynchronous read fails.
It will cause ctx->rc is error.

Example:
Share a directory and create a file on the Windows OS.
Mount the directory to the Linux OS using CIFS.
On the CIFS client of the Linux OS, invoke the pread interface to
deliver the read request.

The size of the read length plus offset of the read request is greater
than the maximum file size.

In this case, the CIFS server on the Windows OS returns a failure
message (for example, the return value of
smb2.nt_status is STATUS_INVALID_PARAMETER).

After receiving the response message, the CIFS client parses
smb2.nt_status to STATUS_INVALID_PARAMETER
and converts it to the Linux error code (rdata->result=-22).

Then the CIFS client invokes the collect_uncached_read_data function to
assign the value of rdata->result to rc, that is, rc=rdata->result=-22.

The type of the ctx->total_len variable is unsigned integer,
the type of the rc variable is integer, and the type of
the ctx->rc variable is ssize_t.

Therefore, during the ternary operation, the value of rc is
automatically converted to an unsigned number. The final result is
ctx->rc=4294967274. However, the expected result is ctx->rc=-22.

Signed-off-by: Yilu Lin <linyilu@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-22 22:49:10 -05:00
Murphy Zhou
ef4a632ccc CIFS: check new file size when extending file by fallocate
xfstests generic/228 checks if fallocate respect RLIMIT_FSIZE.
After fallocate mode 0 extending enabled, we can hit this failure.
Fix this by check the new file size with vfs helper, return
error if file size is larger then RLIMIT_FSIZE(ulimit -f).

This patch has been tested by LTP/xfstests aginst samba and
Windows server.

Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-03-22 22:49:10 -05:00
Steve French
8895c66f2b SMB3: Minor cleanup of protocol definitions
And add one missing define (COMPRESSION_TRANSFORM_ID) and
flag (TRANSFORM_FLAG_ENCRYPTED)

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:10 -05:00
Steve French
8f23343131 SMB3: Additional compression structures
New transform header structures. See recent updates
to MS-SMB2 adding section 2.2.42.1 and 2.2.42.2

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-22 22:49:10 -05:00
Steve French
2fe4f62de4 SMB3: Add new compression flags
Additional compression capabilities can now be negotiated and a
new compression algorithm.  Add the flags for these.

See newly updated MS-SMB2 sections 3.1.4.4.1 and 2.2.3.1.3

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-22 22:49:10 -05:00
Gustavo A. R. Silva
cff2def598 cifs: smb2pdu.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:10 -05:00
Eric Biggers
dc920277f1 cifs: clear PF_MEMALLOC before exiting demultiplex thread
Leaving PF_MEMALLOC set when exiting a kthread causes it to remain set
during do_exit().  That can confuse things.  For example, if BSD process
accounting is enabled and the accounting file has FS_SYNC_FL set and is
located on an ext4 filesystem without a journal, then do_exit() can end
up calling ext4_write_inode().  That triggers the
WARN_ON_ONCE(current->flags & PF_MEMALLOC) there, as it assumes
(appropriately) that inodes aren't written when allocating memory.

This was originally reported for another kernel thread, xfsaild() [1].
cifs_demultiplex_thread() also exits with PF_MEMALLOC set, so it's
potentially subject to this same class of issue -- though I haven't been
able to reproduce the WARN_ON_ONCE() via CIFS, since unlike xfsaild(),
cifs_demultiplex_thread() is sent SIGKILL before exiting, and that
interrupts the write to the BSD process accounting file.

Either way, leaving PF_MEMALLOC set is potentially problematic.  Let's
clean this up by properly saving and restoring PF_MEMALLOC.

[1] https://lore.kernel.org/r/0000000000000e7156059f751d7b@google.com

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:10 -05:00
Gustavo A. R. Silva
266b9fecc5 cifs: cifspdu.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:10 -05:00
Steve French
ba55344f36 CIFS: Warn less noisily on default mount
The warning we print on mount about how to use less secure dialects
(when the user does not specify a version on mount) is useful
but is noisy to print on every default mount, and can be changed
to a warn_once.  Slightly updated the warning text as well to note
SMB3.1.1 which has been the default which is typically negotiated
(for a few years now) by most servers.

      "No dialect specified on mount. Default has changed to a more
       secure dialect, SMB2.1 or later (e.g. SMB3.1.1), from CIFS
       (SMB1). To use the less secure SMB1 dialect to access old
       servers which do not support SMB3.1.1 (or even SMB3 or SMB2.1)
       specify vers=1.0 on mount."

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-22 22:49:09 -05:00
Qiujun Huang
f2d67931fd fs/cifs: fix gcc warning in sid_to_id
fix warning [-Wunused-but-set-variable] at variable 'rc',
keeping the code readable.

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Murphy Zhou
0667059d0b cifs: allow unlock flock and OFD lock across fork
Since commit d0677992d2 ("cifs: add support for flock") added
support for flock, LTP/flock03[1] testcase started to fail.

This testcase is testing flock lock and unlock across fork.
The parent locks file and starts the child process, in which
it unlock the same fd and lock the same file with another fd
again. All the lock and unlock operation should succeed.

Now the child process does not actually unlock the file, so
the following lock fails. Fix this by allowing flock and OFD
lock go through the unlock routine, not skipping if the unlock
request comes from another process.

Patch has been tested by LTP/xfstests on samba and Windows
server, v3.11, with or without cache=none mount option.

[1] https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/syscalls/flock/flock03.c
Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-03-22 22:49:09 -05:00
Steve French
c7e9f78f7b cifs: do d_move in rename
See commit 349457ccf2
"Allow file systems to manually d_move() inside of ->rename()"

Lessens possibility of race conditions in rename

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Aurelien Aptel
69dda3059e cifs: add SMB2_open() arg to return POSIX data
allows SMB2_open() callers to pass down a POSIX data buffer that will
trigger requesting POSIX create context and parsing the response into
the provided buffer.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-03-22 22:49:09 -05:00
Aurelien Aptel
3d519bd126 cifs: plumb smb2 POSIX dir enumeration
* add code to request POSIX info level
* parse dir entries and fill cifs_fattr to get correct inode data

since the POSIX payload is variable size the number of entries in a
FIND response needs to be computed differently.

Dirs and regular files are properly reported along with mode bits,
hardlink number, c/m/atime. No special files yet (see below).

Current experimental version of Samba with the extension unfortunately
has issues with wildcards and needs the following patch:

> --- i/source3/smbd/smb2_query_directory.c
> +++ w/source3/smbd/smb2_query_directory.c
> @@ -397,9 +397,7 @@ smbd_smb2_query_directory_send(TALLOC_CTX
> *mem_ctx,
> 		}
> 	}
>
> -       if (!state->smbreq->posix_pathnames) {
> 		wcard_has_wild = ms_has_wild(state->in_file_name);
> -       }
>
> 	/* Ensure we've canonicalized any search path if not a wildcard. */
> 	if (!wcard_has_wild) {
>

Also for special files despite reporting them as reparse point samba
doesn't set the reparse tag field. This patch will mark them as needing
re-evaluation but the re-evaluate code doesn't deal with it yet.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Aurelien Aptel
349e13ad30 cifs: add smb2 POSIX info level
* add new info level and structs for SMB2 posix extension
* add functions to parse and validate it

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Aurelien Aptel
2e8af978d9 cifs: rename posix create rsp
little progress on the posix create response.

* rename struct to create_posix_rsp to match with the request
  create_posix context
* make struct packed
* pass smb info struct for parse_posix_ctxt to fill
* use smb info struct as param
* update TODO

What needs to be done:

SMB2_open() has an optional smb info out argument that it will fill.
Callers making use of this are:

- smb3_query_mf_symlink (need to investigate)
- smb2_open_file

Callers of smb2_open_file (via server->ops->open) are passing an
smbinfo struct but that struct cannot hold POSIX information. All the
call stack needs to be changed for a different info type. Maybe pass
SMB generic struct like cifs_fattr instead.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Steve French
8fe0c2c2cb cifs: print warning mounting with vers=1.0
We really, really don't want people using insecure dialects
unless they realize what they are doing ...

Add mount warning if mounting with vers=1.0 (older SMB1/CIFS
dialect) instead of the default (SMB2.1 or later, typically
SMB3.1.1).

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-03-22 22:49:09 -05:00
Steve French
cf5371ae46 smb3: fix performance regression with setting mtime
There are cases when we don't want to send the SMB2 flush operation
(e.g. when user specifies mount parm "nostrictsync") and it can be
a very expensive operation on the server.  In most cases in order
to set mtime, we simply need to flush (write) the dirtry pages from
the client and send the writes to the server not also send a flush
protocol operation to the server.

Fixes: aa081859b1 ("cifs: flush before set-info if we have writeable handles")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Stefan Metzmacher
864138cb31 cifs: make use of cap_unix(ses) in cifs_reconnect_tcon()
cap_unix(ses) defaults to false for SMB2.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Stefan Metzmacher
b08484d715 cifs: use mod_delayed_work() for &server->reconnect if already queued
mod_delayed_work() is safer than queue_delayed_work() if there's a
chance that the work is already in the queue.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Stefan Metzmacher
e2e87519bd cifs: call wake_up(&server->response_q) inside of cifs_reconnect()
This means it's consistently called and the callers don't need to
care about it.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Paulo Alcantara (SUSE)
bacd704a95 cifs: handle prefix paths in reconnect
For the case where we have a DFS path like below and we're currently
connected to targetA:

    //dfsroot/link -> //targetA/share/foo, //targetB/share/bar

after failover, we should make sure to update cifs_sb->prepath so the
next operations will use the new prefix path "/bar".

Besides, in order to simplify the use of different prefix paths,
enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to
revalidate the root dentry every time we set a new prefix path.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Steve French
ffdec8d642 cifs: do not ignore the SYNC flags in getattr
Check the AT_STATX_FORCE_SYNC flag and force an attribute
revalidation if requested by the caller, and if the caller
specificies AT_STATX_DONT_SYNC only revalidate cached attributes
if required.  In addition do not flush writes in getattr (which
can be expensive) if size or timestamps not requested by the
caller.

Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00
Linus Torvalds
cd607737f3 three small smb3 fixes, 2 for stable
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Merge tag '5.6-rc6-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three small smb3 fixes, two for stable"

* tag '5.6-rc6-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: fiemap: do not return EINVAL if get nothing
  CIFS: Increment num_remote_opens stats counter even in case of smb2_query_dir_first
  cifs: potential unintitliazed error code in cifs_getattr()
2020-03-19 10:19:11 -07:00
Linus Torvalds
dcf23ac3e8 locks: reinstate locks_delete_block optimization
There is measurable performance impact in some synthetic tests due to
commit 6d390e4b5d (locks: fix a potential use-after-free problem when
wakeup a waiter). Fix the race condition instead by clearing the
fl_blocker pointer after the wake_up, using explicit acquire/release
semantics.

This does mean that we can no longer use the clearing of fl_blocker as
the wait condition, so switch the waiters over to checking whether the
fl_blocked_member list_head is empty.

Reviewed-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Fixes: 6d390e4b5d (locks: fix a potential use-after-free problem when wakeup a waiter)
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-18 13:03:38 -07:00
Murphy Zhou
979a2665eb CIFS: fiemap: do not return EINVAL if get nothing
If we call fiemap on a truncated file with none blocks allocated,
it makes sense we get nothing from this call. No output means
no blocks have been counted, but the call succeeded. It's a valid
response.

Simple example reproducer:
xfs_io -f 'truncate 2M' -c 'fiemap -v' /cifssch/testfile
xfs_io: ioctl(FS_IOC_FIEMAP) ["/cifssch/testfile"]: Invalid argument

Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-03-17 13:27:06 -05:00
Shyam Prasad N
1be1fa42eb CIFS: Increment num_remote_opens stats counter even in case of smb2_query_dir_first
The num_remote_opens counter keeps track of the number of open files which must be
maintained by the server at any point. This is a per-tree-connect counter, and the value
of this counter gets displayed in the /proc/fs/cifs/Stats output as a following...

Open files: 0 total (local), 1 open on server
                             ^^^^^^^^^^^^^^^^
As a thumb-rule, we want to increment this counter for each open/create that we
successfully execute on the server. Similarly, we should decrement the counter when
we successfully execute a close.

In this case, an increment was being missed in case of smb2_query_dir_first,
in case of successful open. As a result, we would underflow the counter and we
could even see the counter go to negative after sufficient smb2_query_dir_first calls.

I tested the stats counter for a bunch of filesystem operations with the fix.
And it looks like the counter looks correct to me.

I also check if we missed the increments and decrements elsewhere. It does not
seem so. Few other cases where an open is done and we don't increment the counter are
the compound calls where the corresponding close is also sent in the request.

Signed-off-by: Shyam Prasad N <nspmangalore@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-03-17 13:27:03 -05:00
Dan Carpenter
39946886fc cifs: potential unintitliazed error code in cifs_getattr()
Smatch complains that "rc" could be uninitialized.

    fs/cifs/inode.c:2206 cifs_getattr() error: uninitialized symbol 'rc'.

Changing it to "return 0;" improves readability as well.

Fixes: cc1baf98c8f6 ("cifs: do not ignore the SYNC flags in getattr")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-17 13:26:26 -05:00
Linus Torvalds
807f030b44 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "A couple of fixes for old crap in ->atomic_open() instances"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  cifs_atomic_open(): fix double-put on late allocation failure
  gfs2_atomic_open(): fix O_EXCL|O_CREAT handling on cold dcache
2020-03-12 15:51:26 -07:00
Al Viro
d9a9f4849f cifs_atomic_open(): fix double-put on late allocation failure
several iterations of ->atomic_open() calling conventions ago, we
used to need fput() if ->atomic_open() failed at some point after
successful finish_open().  Now (since 2016) it's not needed -
struct file carries enough state to make fput() work regardless
of the point in struct file lifecycle and discarding it on
failure exits in open() got unified.  Unfortunately, I'd missed
the fact that we had an instance of ->atomic_open() (cifs one)
that used to need that fput(), as well as the stale comment in
finish_open() demanding such late failure handling.  Trivially
fixed...

Fixes: fe9ec8291f "do_last(): take fput() on error after opening to out:"
Cc: stable@kernel.org # v4.7+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-12 18:25:20 -04:00
Joe Perches
fb4b5f1346 cifs: Use #define in cifs_dbg
All other uses of cifs_dbg use defines so change this one.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-24 14:20:38 -06:00
Aurelien Aptel
86f740f2ae cifs: fix rename() by ensuring source handle opened with DELETE bit
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>
2020-02-24 14:20:38 -06:00
Steve French
ec57010acd cifs: add missing mount option to /proc/mounts
We were not displaying the mount option "signloosely" in /proc/mounts
for cifs mounts which some users found confusing recently

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-24 14:20:38 -06:00
Paulo Alcantara (SUSE)
1542552338 cifs: fix potential mismatch of UNC paths
Ensure that full_path is an UNC path that contains '\\' as delimiter,
which is required by cifs_build_devname().

The build_path_from_dentry_optional_prefix() function may return a
path with '/' as delimiter when using SMB1 UNIX extensions, for
example.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-02-24 14:20:38 -06:00
Ronnie Sahlberg
fc513fac56 cifs: don't leak -EAGAIN for stat() during reconnect
If from cifs_revalidate_dentry_attr() the SMB2/QUERY_INFO call fails with an
error, such as STATUS_SESSION_EXPIRED, causing the session to be reconnected
it is possible we will leak -EAGAIN back to the application even for
system calls such as stat() where this is not a valid error.

Fix this by re-trying the operation from within cifs_revalidate_dentry_attr()
if cifs_get_inode_info*() returns -EAGAIN.

This fixes stat() and possibly also other system calls that uses
cifs_revalidate_dentry*().

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: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2020-02-24 14:20:38 -06:00
Ronnie Sahlberg
85db6b7ae6 cifs: make sure we do not overflow the max EA buffer size
RHBZ: 1752437

Before we add a new EA we should check that this will not overflow
the maximum buffer we have available to read the EAs back.
Otherwise we can get into a situation where the EAs are so big that
we can not read them back to the client and thus we can not list EAs
anymore or delete them.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-02-14 11:10:24 -06:00
Steve French
2c6251ad91 cifs: enable change notification for SMB2.1 dialect
It was originally enabled only for SMB3 or later dialects, but
had requests to add it to SMB2.1 mounts as well given the
large number of systems at that dialect level.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: L Walsh <cifs@tlinx.org>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-02-14 11:10:06 -06:00
Frank Sorenson
f52aa79df4 cifs: Fix mode output in debugging statements
A number of the debug statements output file or directory mode
in hex.  Change these to print using octal.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-12 22:24:26 -06:00
Petr Pavlu
3f6166aaf1 cifs: fix mount option display for sec=krb5i
Fix display for sec=krb5i which was wrongly interleaved by cruid,
resulting in string "sec=krb5,cruid=<...>i" instead of
"sec=krb5i,cruid=<...>".

Fixes: 96281b9e46 ("smb3: for kerberos mounts display the credential uid used")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-10 08:32:30 -06:00
Linus Torvalds
d1ea35f4cd 13 cifs/smb3 patches most from testing at the SMB3 plugfest this week
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Merge tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "13 cifs/smb3 patches, most from testing at the SMB3 plugfest this week:

   - Important fix for multichannel and for modefromsid mounts.

   - Two reconnect fixes

   - Addition of SMB3 change notify support

   - Backup tools fix

   - A few additional minor debug improvements (tracepoints and
     additional logging found useful during testing this week)"

* tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: Add defines for new information level, FileIdInformation
  smb3: print warning once if posix context returned on open
  smb3: add one more dynamic tracepoint missing from strict fsync path
  cifs: fix mode bits from dir listing when mounted with modefromsid
  cifs: fix channel signing
  cifs: add SMB3 change notification support
  cifs: make multichannel warning more visible
  cifs: fix soft mounts hanging in the reconnect code
  cifs: Add tracepoints for errors on flush or fsync
  cifs: log warning message (once) if out of disk space
  cifs: fail i/o on soft mounts if sessionsetup errors out
  smb3: fix problem with null cifs super block with previous patch
  SMB3: Backup intent flag missing from some more ops
2020-02-09 13:27:17 -08:00
Steve French
51d92d69f7 smb3: Add defines for new information level, FileIdInformation
See MS-FSCC 2.4.43.  Valid to be quried from most
Windows servers (among others).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-06 17:32:24 -06:00
Steve French
ab3459d8f0 smb3: print warning once if posix context returned on open
SMB3.1.1 POSIX Context processing is not complete yet - so print warning
(once) if server returns it on open.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-06 17:31:56 -06:00
Steve French
2391ca41b4 smb3: add one more dynamic tracepoint missing from strict fsync path
We didn't have a dynamic trace point for catching errors in
file_write_and_wait_range error cases in cifs_strict_fsync.

Since not all apps check for write behind errors, it can be
important for debugging to be able to trace these error
paths.

Suggested-and-reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-06 17:21:23 -06:00
Aurelien Aptel
e3e056c351 cifs: fix mode bits from dir listing when mounted with modefromsid
When mounting with -o modefromsid, the mode bits are stored in an
ACE. Directory enumeration (e.g. ls -l /mnt) triggers an SMB Query Dir
which does not include ACEs in its response. The mode bits in this
case are silently set to a default value of 755 instead.

This patch marks the dentry created during the directory enumeration
as needing re-evaluation (i.e. additional Query Info with ACEs) so
that the mode bits can be properly extracted.

Quick repro:

$ mount.cifs //win19.test/data /mnt -o ...,modefromsid
$ touch /mnt/foo && chmod 751 /mnt/foo
$ stat /mnt/foo
  # reports 751 (OK)
$ sleep 2
  # dentry older than 1s by default get invalidated
$ ls -l /mnt
  # since dentry invalid, ls does a Query Dir
  # and reports foo as 755 (WRONG)

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-06 17:19:38 -06:00
Aurelien Aptel
cc95b67727 cifs: fix channel signing
The server var was accidentally used as an iterator over the global
list of connections, thus overwritten the passed argument. This
resulted in the wrong signing key being returned for extra channels.

Fix this by using a separate var to iterate.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-06 12:42:36 -06:00
Steve French
d26c2ddd33 cifs: add SMB3 change notification support
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>
2020-02-06 09:14:28 -06:00
Aurelien Aptel
343a1b777a cifs: make multichannel warning more visible
When no interfaces are returned by the server we cannot open multiple
channels. Make it more obvious by reporting that to the user at the
VFS log level.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-06 09:12:16 -06:00
Ronnie Sahlberg
09c40b1535 cifs: fix soft mounts hanging in the reconnect code
RHBZ: 1795423

This is the SMB1 version of a patch we already have for SMB2

In recent DFS updates we have a new variable controlling how many times we will
retry to reconnect the share.
If DFS is not used, then this variable is initialized to 0 in:

static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
{
        return tl ? tl->tl_numtgts : 0;
}

This means that in the reconnect loop in smb2_reconnect() we will immediately wrap retries to -1
and never actually get to pass this conditional:

                if (--retries)
                        continue;

The effect is that we no longer reach the point where we fail the commands with -EHOSTDOWN
and basically the kernel threads are virtually hung and unkillable.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-02-06 09:12:00 -06:00
Steve French
f2bf09e97b cifs: Add tracepoints for errors on flush or fsync
Makes it easier to debug errors on writeback that happen later,
and are being returned on flush or fsync

For example:
  writetest-17829 [002] .... 13583.407859: cifs_flush_err: ino=90 rc=-28

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-05 18:24:19 -06:00
Steve French
d6fd41905e cifs: log warning message (once) if out of disk space
We ran into a confusing problem where an application wasn't checking
return code on close and so user didn't realize that the application
ran out of disk space.  log a warning message (once) in these
cases. For example:

  [ 8407.391909] Out of space writing to \\oleg-server\small-share

Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Oleg Kravtsov <oleg@tuxera.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-02-05 17:58:52 -06:00
Ronnie Sahlberg
b0dd940e58 cifs: fail i/o on soft mounts if sessionsetup errors out
RHBZ: 1579050

If we have a soft mount we should fail commands for session-setup
failures (such as the password having changed/ account being deleted/ ...)
and return an error back to the application.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2020-02-05 06:32:41 -06:00
Steve French
87f93d82e0 smb3: fix problem with null cifs super block with previous patch
Add check for null cifs_sb to create_options helper

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-02-05 06:32:19 -06:00
Linus Torvalds
bddea11b1b Merge branch 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs timestamp updates from Al Viro:
 "More 64bit timestamp work"

* 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  kernfs: don't bother with timestamp truncation
  fs: Do not overload update_time
  fs: Delete timespec64_trunc()
  fs: ubifs: Eliminate timespec64_trunc() usage
  fs: ceph: Delete timespec64_trunc() usage
  fs: cifs: Delete usage of timespec64_trunc
  fs: fat: Eliminate timespec64_trunc() usage
  utimes: Clamp the timestamps in notify_change()
2020-02-05 05:02:42 +00:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Amir Goldstein
0f060936e4 SMB3: Backup intent flag missing from some more ops
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>
2020-02-03 16:12:47 -06:00
Steve French
b581098482 cifs: update internal module version number
To 2.25

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-31 15:13:22 -06:00
Ronnie Sahlberg
c54849ddd8 cifs: fix soft mounts hanging in the reconnect code
RHBZ: 1795429

In recent DFS updates we have a new variable controlling how many times we will
retry to reconnect the share.
If DFS is not used, then this variable is initialized to 0 in:

static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
{
        return tl ? tl->tl_numtgts : 0;
}

This means that in the reconnect loop in smb2_reconnect() we will immediately wrap retries to -1
and never actually get to pass this conditional:

                if (--retries)
                        continue;

The effect is that we no longer reach the point where we fail the commands with -EHOSTDOWN
and basically the kernel threads are virtually hung and unkillable.

Fixes: a3a53b7603 (cifs: Add support for failover in smb2_reconnect())
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
2020-01-30 15:23:55 -06:00
Vincent Whitchurch
f1f27ad745 CIFS: Fix task struct use-after-free on reconnect
The task which created the MID may be gone by the time cifsd attempts to
call the callbacks on MIDs from cifs_reconnect().

This leads to a use-after-free of the task struct in cifs_wake_up_task:

 ==================================================================
 BUG: KASAN: use-after-free in __lock_acquire+0x31a0/0x3270
 Read of size 8 at addr ffff8880103e3a68 by task cifsd/630

 CPU: 0 PID: 630 Comm: cifsd Not tainted 5.5.0-rc6+ #119
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
 Call Trace:
  dump_stack+0x8e/0xcb
  print_address_description.constprop.5+0x1d3/0x3c0
  ? __lock_acquire+0x31a0/0x3270
  __kasan_report+0x152/0x1aa
  ? __lock_acquire+0x31a0/0x3270
  ? __lock_acquire+0x31a0/0x3270
  kasan_report+0xe/0x20
  __lock_acquire+0x31a0/0x3270
  ? __wake_up_common+0x1dc/0x630
  ? _raw_spin_unlock_irqrestore+0x4c/0x60
  ? mark_held_locks+0xf0/0xf0
  ? _raw_spin_unlock_irqrestore+0x39/0x60
  ? __wake_up_common_lock+0xd5/0x130
  ? __wake_up_common+0x630/0x630
  lock_acquire+0x13f/0x330
  ? try_to_wake_up+0xa3/0x19e0
  _raw_spin_lock_irqsave+0x38/0x50
  ? try_to_wake_up+0xa3/0x19e0
  try_to_wake_up+0xa3/0x19e0
  ? cifs_compound_callback+0x178/0x210
  ? set_cpus_allowed_ptr+0x10/0x10
  cifs_reconnect+0xa1c/0x15d0
  ? generic_ip_connect+0x1860/0x1860
  ? rwlock_bug.part.0+0x90/0x90
  cifs_readv_from_socket+0x479/0x690
  cifs_read_from_socket+0x9d/0xe0
  ? cifs_readv_from_socket+0x690/0x690
  ? mempool_resize+0x690/0x690
  ? rwlock_bug.part.0+0x90/0x90
  ? memset+0x1f/0x40
  ? allocate_buffers+0xff/0x340
  cifs_demultiplex_thread+0x388/0x2a50
  ? cifs_handle_standard+0x610/0x610
  ? rcu_read_lock_held_common+0x120/0x120
  ? mark_lock+0x11b/0xc00
  ? __lock_acquire+0x14ed/0x3270
  ? __kthread_parkme+0x78/0x100
  ? lockdep_hardirqs_on+0x3e8/0x560
  ? lock_downgrade+0x6a0/0x6a0
  ? lockdep_hardirqs_on+0x3e8/0x560
  ? _raw_spin_unlock_irqrestore+0x39/0x60
  ? cifs_handle_standard+0x610/0x610
  kthread+0x2bb/0x3a0
  ? kthread_create_worker_on_cpu+0xc0/0xc0
  ret_from_fork+0x3a/0x50

 Allocated by task 649:
  save_stack+0x19/0x70
  __kasan_kmalloc.constprop.5+0xa6/0xf0
  kmem_cache_alloc+0x107/0x320
  copy_process+0x17bc/0x5370
  _do_fork+0x103/0xbf0
  __x64_sys_clone+0x168/0x1e0
  do_syscall_64+0x9b/0xec0
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 Freed by task 0:
  save_stack+0x19/0x70
  __kasan_slab_free+0x11d/0x160
  kmem_cache_free+0xb5/0x3d0
  rcu_core+0x52f/0x1230
  __do_softirq+0x24d/0x962

 The buggy address belongs to the object at ffff8880103e32c0
  which belongs to the cache task_struct of size 6016
 The buggy address is located 1960 bytes inside of
  6016-byte region [ffff8880103e32c0, ffff8880103e4a40)
 The buggy address belongs to the page:
 page:ffffea000040f800 refcount:1 mapcount:0 mapping:ffff8880108da5c0
 index:0xffff8880103e4c00 compound_mapcount: 0
 raw: 4000000000010200 ffffea00001f2208 ffffea00001e3408 ffff8880108da5c0
 raw: ffff8880103e4c00 0000000000050003 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff8880103e3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880103e3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 >ffff8880103e3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                           ^
  ffff8880103e3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880103e3b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

This can be reliably reproduced by adding the below delay to
cifs_reconnect(), running find(1) on the mount, restarting the samba
server while find is running, and killing find during the delay:

  	spin_unlock(&GlobalMid_Lock);
  	mutex_unlock(&server->srv_mutex);

 +	msleep(10000);
 +
  	cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
  	list_for_each_safe(tmp, tmp2, &retry_list) {
  		mid_entry = list_entry(tmp, struct mid_q_entry, qhead);

Fix this by holding a reference to the task struct until the MID is
freed.

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00
Chen Zhou
050d2a8b69 cifs: use PTR_ERR_OR_ZERO() to simplify code
PTR_ERR_OR_ZERO contains if(IS_ERR(...)) + PTR_ERR, just use
PTR_ERR_OR_ZERO directly.

Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-01-26 19:24:17 -06:00
Ronnie Sahlberg
8bd0d70144 cifs: add support for fallocate mode 0 for non-sparse files
RHBZ 1336264

When we extend a file we must also force the size to be updated.

This fixes an issue with holetest in xfs-tests which performs the following
sequence :
1, create a new file
2, use fallocate mode==0 to populate the file
3, mmap the file
4, touch each page by reading the mmapped region.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
Ronnie Sahlberg
fe12926863 cifs: fix NULL dereference in match_prepath
RHBZ: 1760879

Fix an oops in match_prepath() by making sure that the prepath string is not
NULL before we pass it into strcmp().

This is similar to other checks we make for example in cifs_root_iget()

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26 19:24:17 -06:00
Steve French
643fbceef4 smb3: fix default permissions on new files when mounting with modefromsid
When mounting with "modefromsid" mount parm most servers will require
that some default permissions are given to users in the ACL on newly
created files, files created with the new 'sd context' - when passing in
an sd context on create, permissions are not inherited from the parent
directory, so in addition to the ACE with the special SID which contains
the mode, we also must pass in an ACE allowing users to access the file
(GENERIC_ALL for authenticated users seemed like a reasonable default,
although later we could allow a mount option or config switch to make
it GENERIC_ALL for EVERYONE special sid).

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-By: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00