linux-toradex.git/fs/cifs/smb2misc.c, branch v4.4.124

Handle mismatched open calls

2017-05-08T05:46:01+00:00

commit 38bd49064a1ecb67baad33598e3d824448ab11ec upstream.

A signal can interrupt a SendReceive call which result in incoming
responses to the call being ignored. This is a problem for calls such as
open which results in the successful response being ignored. This
results in an open file resource on the server.

The patch looks into responses which were cancelled after being sent and
in case of successful open closes the open fids.

For this patch, the check is only done in SendReceive2()

RH-bz: 1403319

Signed-off-by: Sachin Prabhu 
Reviewed-by: Pavel Shilovsky 
Acked-by: Sachin Prabhu 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Greg Kroah-Hartman

Clarify locking of cifs file and tcon structures and make more granular

2016-10-28T07:01:32+00:00

commit 3afca265b5f53a0b15b79531c13858049505582d upstream.

Remove the global file_list_lock to simplify cifs/smb3 locking and
have spinlocks that more closely match the information they are
protecting.

Add new tcon->open_file_lock and file->file_info_lock spinlocks.
Locks continue to follow a heirachy,
	cifs_socket --> cifs_ses --> cifs_tcon --> cifs_file
where global tcp_ses_lock still protects socket and cifs_ses, while the
the newer locks protect the lower level structure's information
(tcon and cifs_file respectively).

Signed-off-by: Steve French 
Signed-off-by: Pavel Shilovsky 
Reviewed-by: Aurelien Aptel 
Reviewed-by: Germano Percossi 
Signed-off-by: Greg Kroah-Hartman

VFS: normal filesystems (and lustre): d_inode() annotations

2015-04-15T19:06:57+00:00

that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells 
Signed-off-by: Al Viro

Fix coverity warning

2015-04-01T05:01:47+00:00

Coverity reports a warning for referencing the beginning of the
SMB2/SMB3 frame using the ProtocolId field as an array. Although
it works the same either way, this patch should quiet the warning
and might be a little clearer.

Reported by Coverity (CID 741269)

Signed-off-by: Steve French 
Acked-by: Shirish Pargaonkar 
Acked-by: Sachin Prabhu 
Reviewed-by: Jeff Layton

Convert MessageID in smb2_hdr to LE

2014-12-14T20:55:45+00:00

We have encountered failures when When testing smb2 mounts on ppc64
machines when using both Samba as well as Windows 2012.

On poking around, the problem was determined to be caused by the
high endian MessageID passed in the header for smb2. On checking the
corresponding MID for smb1 is converted to LE before being sent on the
wire.

We have tested this patch successfully on a ppc64 machine.

Signed-off-by: Sachin Prabhu

fs/cifs: remove obsolete __constant

2014-12-11T01:41:02+00:00

Replace all __constant_foo to foo() except in smb2status.h (1700 lines to
update).

Signed-off-by: Fabian Frederick 
Cc: Steve French 
Cc: Jeff Layton 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Allow conversion of characters in Mac remap range (part 2)

2014-10-16T20:20:20+00:00

The previous patch allowed remapping reserved characters from directory
listenings, this patch adds conversion the other direction, allowing
opening of files with any of the seven reserved characters.

Signed-off-by: Steve French 
Reviewed-by: Shirish Pargaonkar

[CIFS] Workaround MacOS server problem with SMB2.1 write

2014-08-16T04:49:01+00:00

 response

Writes fail to Mac servers with SMB2.1 mounts (works with cifs though) due
to them sending an incorrect RFC1001 length for the SMB2.1 Write response.
Workaround this problem. MacOS server sends a write response with 3 bytes
of pad beyond the end of the SMB itself.  The RFC1001 length is 3 bytes
more than the sum of the SMB2.1 header length + the write reponse.

Incorporate feedback from Jeff and JRA to allow servers to send
a tcp frame that is even more than three bytes too long
(ie much longer than the SMB2/SMB3 request that it contains) but
we do log it once now. In the earlier version of the patch I had
limited how far off the length field could be before we fail the request.

Signed-off-by: Steve French

[CIFS] Fix incorrect hex vs. decimal in some debug print statements

2014-08-03T02:16:48+00:00

Joe Perches and Hans Wennborg noticed that various places in the
kernel were printing decimal numbers with 0x prefix.
    printk("0x%d") or equivalent
This fixes the instances of this in the cifs driver.

CC: Hans Wennborg 
CC: Joe Perches 
Signed-off-by: Steve French

cifs: Wait for writebacks to complete before attempting write.

2014-04-16T18:51:46+00:00

Problem reported in Red Hat bz 1040329 for strict writes where we cache
only when we hold oplock and write direct to the server when we don't.

When we receive an oplock break, we first change the oplock value for
the inode in cifsInodeInfo->oplock to indicate that we no longer hold
the oplock before we enqueue a task to flush changes to the backing
device. Once we have completed flushing the changes, we return the
oplock to the server.

There are 2 ways here where we can have data corruption
1) While we flush changes to the backing device as part of the oplock
break, we can have processes write to the file. These writes check for
the oplock, find none and attempt to write directly to the server.
These direct writes made while we are flushing from cache could be
overwritten by data being flushed from the cache causing data
corruption.
2) While a thread runs in cifs_strict_writev, the machine could receive
and process an oplock break after the thread has checked the oplock and
found that it allows us to cache and before we have made changes to the
cache. In that case, we end up with a dirty page in cache when we
shouldn't have any. This will be flushed later and will overwrite all
subsequent writes to the part of the file represented by this page.

Before making any writes to the server, we need to confirm that we are
not in the process of flushing data to the server and if we are, we
should wait until the process is complete before we attempt the write.
We should also wait for existing writes to complete before we process
an oplock break request which changes oplock values.

We add a version specific  downgrade_oplock() operation to allow for
differences in the oplock values set for the different smb versions.

Cc: stable@vger.kernel.org
Signed-off-by: Sachin Prabhu 
Reviewed-by: Jeff Layton 
Reviewed-by: Pavel Shilovsky 
Signed-off-by: Steve French