linux-toradex.git/fs/cifs, branch v3.14.4

cifs: mask off top byte in get_rfc1002_length()

2014-02-28T20:01:14+00:00

The rfc1002 length actually includes a type byte, which we aren't
masking off. In most cases, it's not a problem since the
RFC1002_SESSION_MESSAGE type is 0, but when doing a RFC1002 session
establishment, the type is non-zero and that throws off the returned
length.

Signed-off-by: Jeff Layton 
Tested-by: Sachin Prabhu 
Signed-off-by: Steve French

cifs: sanity check length of data to send before sending

2014-02-24T02:55:07+00:00

We had a bug discovered recently where an upper layer function
(cifs_iovec_write) could pass down a smb_rqst with an invalid amount of
data in it. The length of the SMB frame would be correct, but the rqst
struct would cause smb_send_rqst to send nearly 4GB of data.

This should never be the case. Add some sanity checking to the beginning
of smb_send_rqst that ensures that the amount of data we're going to
send agrees with the length in the RFC1002 header. If it doesn't, WARN()
and return -EIO to the upper layers.

Signed-off-by: Jeff Layton 
Acked-by: Sachin Prabhu 
Reviewed-by: Pavel Shilovsky 
Signed-off-by: Steve French

CIFS: Fix wrong pos argument of cifs_find_lock_conflict

2014-02-24T02:54:50+00:00

and use generic_file_aio_write rather than __generic_file_aio_write
in cifs_writev.

Signed-off-by: Pavel Shilovsky 
Reported-by: Al Viro 
Signed-off-by: Steve French

Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6

2014-02-17T21:50:11+00:00

Pull CIFS fixes from Steve French:
 "Three cifs fixes, the most important fixing the problem with passing
  bogus pointers with writev (CVE-2014-0069).

  Two additional cifs fixes are still in review (including the fix for
  an append problem which Al also discovered)"

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix too big maxBuf size for SMB3 mounts
  cifs: ensure that uncached writes handle unmapped areas correctly
  [CIFS] Fix cifsacl mounts over smb2 to not call cifs

CIFS: Fix too big maxBuf size for SMB3 mounts

2014-02-14T22:50:47+00:00

SMB3 servers can respond with MaxTransactSize of more than 4M
that can cause a memory allocation error returned from kmalloc
in a lock codepath. Also the client doesn't support multicredit
requests now and allows buffer sizes of 65536 bytes only. Set
MaxTransactSize to this maximum supported value.

Cc: stable@vger.kernel.org # 3.7+
Signed-off-by: Pavel Shilovsky 
Acked-by: Jeff Layton 
Signed-off-by: Steve French

cifs: ensure that uncached writes handle unmapped areas correctly

2014-02-14T22:46:15+00:00

It's possible for userland to pass down an iovec via writev() that has a
bogus user pointer in it. If that happens and we're doing an uncached
write, then we can end up getting less bytes than we expect from the
call to iov_iter_copy_from_user. This is CVE-2014-0069

cifs_iovec_write isn't set up to handle that situation however. It'll
blindly keep chugging through the page array and not filling those pages
with anything useful. Worse yet, we'll later end up with a negative
number in wdata->tailsz, which will confuse the sending routines and
cause an oops at the very least.

Fix this by having the copy phase of cifs_iovec_write stop copying data
in this situation and send the last write as a short one. At the same
time, we want to avoid sending a zero-length write to the server, so
break out of the loop and set rc to -EFAULT if that happens. This also
allows us to handle the case where no address in the iovec is valid.

[Note: Marking this for stable on v3.4+ kernels, but kernels as old as
       v2.6.38 may have a similar problem and may need similar fix]

Cc:  # v3.4+
Reviewed-by: Pavel Shilovsky 
Reported-by: Al Viro 
Signed-off-by: Jeff Layton 
Signed-off-by: Steve French

[CIFS] Fix cifsacl mounts over smb2 to not call cifs

2014-02-10T20:08:16+00:00

When mounting with smb2/smb3 (e.g. vers=2.1) and cifsacl mount option,
it was trying to get the mode by querying the acl over the cifs
rather than smb2 protocol.  This patch makes that protocol
independent and makes cifsacl smb2 mounts return a more intuitive
operation not supported error (until we add a worker function
for smb2_get_acl).

Note that a previous patch fixed getxattr/setxattr for the CIFSACL xattr
which would unconditionally call cifs_get_acl and cifs_set_acl (even when
mounted smb2). I made those protocol independent last week (new protocol
version operations "get_acl" and "set_acl" but did not add an
smb2_get_acl and smb2_set_acl yet so those now simply return EOPNOTSUPP
which at least is better than sending cifs requests on smb2 mount)

The previous patches did not fix the one remaining case though ie
mounting with "cifsacl" when getting mode from acl would unconditionally
end up calling "cifs_get_acl_from_fid" even for smb2 - so made that protocol
independent but to make that protocol independent had to make sure that the callers
were passing the protocol independent handle structure (cifs_fid) instead
of cifs specific _u16 network file handle (ie cifs_fid instead of cifs_fid->fid)

Now mount with smb2 and cifsacl mount options will return EOPNOTSUP (instead
of timing out) and a future patch will add smb2 operations (e.g. get_smb2_acl)
to enable this.

Signed-off-by: Steve French

Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

2014-02-10T18:33:50+00:00

Pull CIFS fixes from Steve French:
 "Small fix from Jeff for writepages leak, and some fixes for ACLs and
  xattrs when SMB2 enabled.

  Am expecting another fix from Jeff and at least one more fix (for
  mounting SMB2 with cifsacl) in the next week"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  [CIFS] clean up page array when uncached write send fails
  cifs: use a flexarray in cifs_writedata
  retrieving CIFS ACLs when mounted with SMB2 fails dropping session
  Add protocol specific operation for CIFS xattrs

fix O_SYNC|O_APPEND syncing the wrong range on write()

2014-02-09T20:18:09+00:00

It actually goes back to 2004 ([PATCH] Concurrent O_SYNC write support)
when sync_page_range() had been introduced; generic_file_write{,v}() correctly
synced
	pos_after_write - written .. pos_after_write - 1
but generic_file_aio_write() synced
	pos_before_write .. pos_before_write + written - 1
instead.  Which is not the same thing with O_APPEND, obviously.
A couple of years later correct variant had been killed off when
everything switched to use of generic_file_aio_write().

All users of generic_file_aio_write() are affected, and the same bug
has been copied into other instances of ->aio_write().

The fix is trivial; the only subtle point is that generic_write_sync()
ought to be inlined to avoid calculations useless for the majority of
calls.

Signed-off-by: Al Viro

[CIFS] clean up page array when uncached write send fails

2014-02-08T02:47:00+00:00

In the event that a send fails in an uncached write, or we end up
needing to reissue it (-EAGAIN case), we'll kfree the wdata but
the pages currently leak.

Fix this by adding a new kref release routine for uncached writedata
that releases the pages, and have the uncached codepaths use that.

[original patch by Jeff modified to fix minor formatting problems]

Signed-off-by: Jeff Layton 
Reviewed-by: Pavel Shilovsky 
Signed-off-by: Steve French