We had cases in the previous patch where we were sending the security
descriptor context on SMB3 open (file create) in cases when we hadn't
mounted with with "modefromsid" mount option.

Add check for that mount flag before calling ad_sd_context in
open init.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

When using the special SID to store the mode bits in an ACE (See
http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx)
which is enabled with mount parm "modefromsid" we were not
passing in the mode via SMB3 create (although chmod was enabled).
SMB3 create allows a security descriptor context to be passed
in (which is more atomic and thus preferable to setting the mode
bits after create via a setinfo).

This patch enables setting the mode bits on create when using
modefromsid mount option. In addition it fixes an endian
error in the definition of the Control field flags in the SMB3
security descriptor. It also makes the ACE type of the special
SID better match the documentation (and behavior of servers
which use this to store mode bits in SMB3 ACLs).

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

iface[0] was accessed regardless of the count value and without
locking.

* check count before accessing any ifaces
* make copy of iface list (it's a simple POD array) and use it without
locking.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>

With the addition of SMB session channels, we introduced new TCP
server pointers that have no sessions or tcons associated with them.

In this case, when we started looking for TCP connections, we might
end up picking session channel rather than the master connection,
hence failing to get either a session or a tcon.

In order to fix that, this patch introduces a new "is_channel" field
to TCP_Server_Info structure so we can skip session channels during
lookup of connections.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Since timestamps on files on most servers can be updated at
close, and since timestamps on our dentries default to one
second we can have stale timestamps in some common cases
(e.g. open, write, close, stat, wait one second, stat - will
show different mtime for the first and second stat).

The SMB2/SMB3 protocol allows querying timestamps at close
so add the code to request timestamp and attr information
(which is cheap for the server to provide) to be returned
when a file is closed (it is not needed for the many
paths that call SMB2_close that are from compounded
query infos and close nor is it needed for some of
the cases where a directory close immediately follows a
directory open.

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

close was relayered to allow passing in an async flag which
is no longer needed in this path. Remove the unneeded parameter
"flags" passed in on close.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>

The pointer pneg_ctxt is being initialized with a value that is never
read and it is being updated later with a new value. The assignment
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>

According to the comment in the code and commit log, some apps
expect atime >= mtime; but the introduced code results in
atime==mtime. Fix the comparison to guard against atime<mtime.

Fixes: 9b9c5bea0b96 ("cifs: do not return atime less than mtime")
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: stfrench@microsoft.com
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

Currently when the client creates a cifsFileInfo structure for
a newly opened file, it allocates a list of byte-range locks
with a pointer to the new cfile and attaches this list to the
inode's lock list. The latter happens before initializing all
other fields, e.g. cfile->tlink. Thus a partially initialized
cifsFileInfo structure becomes available to other threads that
walk through the inode's lock list. One example of such a thread
may be an oplock break worker thread that tries to push all
cached byte-range locks. This causes NULL-pointer dereference
in smb2_push_mandatory_locks() when accessing cfile->tlink:

[598428.945633] BUG: kernel NULL pointer dereference, address: 0000000000000038
...
[598428.945749] Workqueue: cifsoplockd cifs_oplock_break [cifs]
[598428.945793] RIP: 0010:smb2_push_mandatory_locks+0xd6/0x5a0 [cifs]
...
[598428.945834] Call Trace:
[598428.945870] ? cifs_revalidate_mapping+0x45/0x90 [cifs]
[598428.945901] cifs_oplock_break+0x13d/0x450 [cifs]
[598428.945909] process_one_work+0x1db/0x380
[598428.945914] worker_thread+0x4d/0x400
[598428.945921] kthread+0x104/0x140
[598428.945925] ? process_one_work+0x380/0x380
[598428.945931] ? kthread_park+0x80/0x80
[598428.945937] ret_from_fork+0x35/0x40

Fix this by reordering initialization steps of the cifsFileInfo
structure: initialize all the fields first and then add the new
byte-range lock list to the inode's lock list.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Pull cifs updates from Steve French:
"Various smb3 fixes (including 12 for stable) and also features
(addition of multichannel support)"

* tag '5.5-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (41 commits)
CIFS: fix a white space issue in cifs_get_inode_info()
cifs: update internal module version number
cifs: Always update signing key of first channel
cifs: Fix retrieval of DFS referrals in cifs_mount()
cifs: Fix potential softlockups while refreshing DFS cache
cifs: Fix lookup of root ses in DFS referral cache
cifs: Fix use-after-free bug in cifs_reconnect()
cifs: dump channel info in DebugData
smb3: dump in_send and num_waiters stats counters by default
cifs: try harder to open new channels
CIFS: Properly process SMB3 lease breaks
cifs: move cifsFileInfo_put logic into a work-queue
cifs: try opening channels after mounting
CIFS: refactor cifs_get_inode_info()
cifs: switch servers depending on binding state
cifs: add server param
cifs: add multichannel mount options and data structs
cifs: sort interface list by speed
CIFS: Fix SMB2 oplock break processing
cifs: don't use 'pre:' for MODULE_SOFTDEP
...

Pull f2fs updates from Jaegeuk Kim:
"In this round, we've introduced fairly small number of patches as below.

Enhancements:
- improve the in-place-update IO flow
- allocate segment to guarantee no GC for pinned files

Bug fixes:
- fix updatetime in lazytime mode
- potential memory leak in f2fs_listxattr
- record parent inode number in rename2 correctly
- fix deadlock in f2fs_gc along with atomic writes
- avoid needless data migration in GC"

* tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: stop GC when the victim becomes fully valid
f2fs: expose main_blkaddr in sysfs
f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
f2fs: show f2fs instance in printk_ratelimited
f2fs: fix potential overflow
f2fs: fix to update dir's i_pino during cross_rename
f2fs: support aligned pinned file
f2fs: avoid kernel panic on corruption test
f2fs: fix wrong description in document
f2fs: cache global IPU bio
f2fs: fix to avoid memory leakage in f2fs_listxattr
f2fs: check total_segments from devices in raw_super
f2fs: update multi-dev metadata in resize_fs
f2fs: mark recovery flag correctly in read_raw_super_block()
f2fs: fix to update time in lazytime mode

We accidentally messed up the indenting on this if statement.

Fixes: 16c696a6c300 ("CIFS: refactor cifs_get_inode_info()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Pull AFS updates from David Howells:
"Minor cleanups and fix:

- Minor fix to make some debugging statements display information
from the correct iov_iter.

- Rename some members and variables to make things more obvious or
consistent.

- Provide a helper to wrap increments of the usage count on the
afs_read struct.

- Use scnprintf() to print into a stack buffer rather than sprintf().

- Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Remove set but not used variable 'ret'
afs: Remove set but not used variables 'before', 'after'
afs: xattr: use scnprintf
afs: Introduce an afs_get_read() refcount helper
afs: Rename desc -> req in afs_fetch_data()
afs: Switch the naming of call->iter and call->_iter
afs: Use call->_iter not &call->iter in debugging statements