This patch adds a missing iscsi_reject->ffffffff assignment within
iscsit_send_reject() code to properly follow RFC-3720 Section 10.17
Bytes 16 -> 19 for the PDU format definition of ISCSI_OP_REJECT.

We've not seen any initiators care about this bytes in practice, but
as Ronnie reported this was causing trouble with wireshark packet
decoding lets go ahead and fix this up now.
Reported-by: NRonnie Sahlberg <ronniesahlberg@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In case of error, the function target_fabric_configfs_init() returns
ERR_PTR() not NULL pointer. The NULL test in the return value check
should be replaced with IS_ERR().

dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes error cases within target_core_init_configfs() to
properly set ret = -ENOMEM before jumping to the out_global exception
path.

This was originally discovered with the following Coccinelle semantic
match information:

Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.  A simplified version of the semantic match
that finds this problem is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>
Signed-off-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Yay, all users of transport_kmap_data_sg now check for a zero-length
request and/or a too-small parameter list length.  We can thus go through
the normal emulation path even for such commands.

This means that out-of-bounds reads and writes are now reported correctly
even if they transfer 0 blocks.  Other errors are also reported correctly.

Testcase: sg_raw /dev/sdb 28 00 80 00 00 00 00 00 00 00
    should fail with ILLEGAL REQUEST / LBA OUT OF RANGE sense
    does not fail without the patch
    (still wrong with the patch, but better: the ASC is INVALID FIELD IN CDB)
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

scsi_setup_fs_cmnd does not like to receive requests with no
bios attached to it.  Special-case zero-length reads and writes,
by not submitting any bio.

Testcase: sg_raw /dev/sdb 28 00 00 00 00 00 00 00 00 00
    should not fail
    panics with the rest of the series but not this patch
    behaves correctly without or with this series
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

READ CAPACITY must be subject to the same treatment as INQUIRY,
REQUEST SENSE, and MODE SENSE, but there are no pre-existing bugs
to fix here.  Just use an on-stack buffer, and copy to it after
checking the return value of transport_kmap_data_sg.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The offset was not bumped back to the full size after writing the
header of the MODE SENSE response, so the last 1 or 2 bytes were
not copied.

On top of this, support zero-length requests by checking for the
return value of transport_kmap_data_sg.

Testcase: sg_raw -r20 /dev/sdb 5a 00 0a 00 00 00 00 00 14 00
    last byte should be 0x1e
    it is 0x00 without the patch
    it is correct with the patch
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

INQUIRY processing already uses an on-heap bounce buffer for loopback,
but not for other fabrics.  Switch this to a cheaper on-stack bounce
buffer, similar to the one used by MODE SENSE and REQUEST SENSE, and
use it unconditionally.  With this in place, zero allocation length is
handled simply by checking the return address of transport_kmap_data_sg.

Testcase: sg_raw /dev/sdb 12 00 83 00 00 00
    should fail with ILLEGAL REQUEST / INVALID FIELD IN CDB sense
    does not fail without the patch
    fails correctly with the series
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Using list_move_tail() instead of list_del() + list_add_tail().

spatch with a semantic match is used to found this problem.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There's no need for iscsi_target_init_negotiation() to print

    iSCSI Login negotiation failed.

on failure, since its only caller (__iscsi_target_login_thread())
prints exactly the same message if it gets an error return back.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch drops se_subsystem_api->[write_cache,fua_write]_emulated flags
set by viritual FILEIO/IBLOCK/RD_MCP backend drivers in favor of explict
TRANSPORT_PLUGIN_PHBA_PDEV checks to know when to fail if userspace is
attempting to set virtual emulation bits for an pSCSI (passthrough)
backend device.
Reported-by: NChristoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Remove including <generated/utsrelease.h> that don't need it.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Remove including <generated/utsrelease.h> that don't need it.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing rd_mcp_template->write_cache_emulated=1 bit to
optionally allow WriteCacheEnabled=1 (WCE) to be enabled for the built-in
TCM/rd_mcp backend driver.

Tested on v3.6-rc[0,2] code with loopback+tcm_vhost fabric ports.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Following commit dbc6e022 from Al Viro for fileio, go ahead and make
Opt_udev_path within iblock_set_configfs_dev_params use match_strlcpy
instead of the match_strdup -> snprintf -> kfree equivalent.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Correct spelling typo in printk and comment within drivers/target.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2.  However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().

So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core.  Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.

(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
      change transport_get_sense_buffer to follow v3.6-rc6 code w/o
      ->set_fabric_sense_len usage)
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

There are no callers of se_tfo->get_fabric_sense_len(), so we should
stop having every fabric driver implement it.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

It's always set, and controls whether uppercase A-F are allowed hex values.
I don't see a reason not to accept these.
Signed-off-by: NAndy Grover <agrover@redhat.com>
Cc: Chris Boot <bootc@bootc.net>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Move static into function body from file scope.

Remove extraneous return statement
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

It is no longer a supported module.
Signed-off-by: NAndy Grover <agrover@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Now that spc_emulate_request_sense has been taught to process zero-length
REQUEST SENSE correctly, drop the special handling of unit attention
conditions from transport_generic_new_cmd.  However, for now REQUEST SENSE
will be the only command that goes through emulation for zero lengths.

(nab: Fix up zero-length check in transport_generic_new_cmd)
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Similar to INQUIRY and MODE SENSE, construct the sense data in a
buffer and later copy it to the scatterlist.  Do not do anything,
but still clear a pending unit attention condition, if the allocation
length is zero.

However, SPC tells us that "If a REQUEST SENSE command is terminated with
CHECK CONDITION status [and] the REQUEST SENSE command was received on
an I_T nexus with a pending unit attention condition (i.e., before the
device server reports CHECK CONDITION status), then the device server
shall not clear the pending unit attention condition."  Do the
transport_kmap_data_sg early to detect this case.

It also tells us "Device servers shall not adjust the additional sense
length to reflect truncation if the allocation length is less than the
sense data available", so do not do that!  Note that the err variable
is write-only.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

In order to support zero-size allocation lengths, do not assert
that we have a scatterlist until after checking cmd->data_length.

But once we do this, we can have two cases of transport_kmap_data_sg
returning NULL: a zero-size allocation length, or an out-of-memory
condition.  Report the latter using sense codes, so that the SCSI
command that triggered it will fail.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

SPC says:

"The ALLOCATION LENGTH field is defined in 4.3.5.6. The allocation length
should be at least 16.  Device servers compliant with SPC return CHECK
CONDITION status, with the sense key set to ILLEGAL REQUEST, and the
additional sense code set to INVALID FIELD IN CDB when the allocation
length is less than 16 bytes".

Testcase: sg_raw -r8 /dev/sdb a0 00 00 00 00 00 00 00 00 08 00 00
    should fail with ILLEGAL REQUEST / INVALID FIELD IN CDB sense
    does not fail without the patch
    fails correctly with the patch
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Several places were not checking that the parameter list length
was large enough, and thus accessing invalid memory.  Zero-length
parameter lists are just a special case of this.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Right now, commands with a zero-size payload are skipped completely.
This is wrong; such commands should be passed down to the device and
processed normally.

For physical backends, this ignores completely things such as START
STOP UNIT.  For virtual backends, we have a hack in place to clear a
unit attention state on a zero-size REQUEST SENSE, but we still do
not report errors properly on zero-length commands---out-of-bounds
0-block reads and writes, too small parameter list lengths, etc.

This patch fixes this for PSCSI.  Uses of transport_kmap_data_sg are
guarded with a check for non-zero cmd->data_length; for all other
commands a zero length is handled properly in pscsi_execute_cmd.
The sole exception will be for now REPORT LUNS, which is handled
through the normal SPC emulation.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The pointer to the sense buffer is fetched by transport_get_sense_data,
but this is called by target_complete_ok_work long after pscsi_req_done
has freed the struct that contains it.

Pass instead the fabric's sense buffer to transport_complete,
and copy the data to it directly in transport_complete.  Setting
SCF_TRANSPORT_TASK_SENSE also becomes a duty of transport_complete.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

The error conditions in transport_get_sense_data are superfluous
and complicate the code unnecessarily:

* SCF_TRANSPORT_TASK_SENSE is checked in the caller;

* it's simply part of the invariants of dev->transport->get_sense_buffer
  that it must be there if transport_complete ever returns 1, and that
  it must not return NULL.  Besides, the entire callback will disappear
  with the next patch.

* similarly in the caller we can expect that sense data is only sent
  for non-zero cmd->scsi_status.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

We will be calling it from transport_complete_cmd, avoid forward
declarations.  No semantic change.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch updates iscsi_login_zero_tsih_s1() usage for generating
iscsi_session->session_index to properly check the return value from
idr_get_new(), and reject the iSCSI login attempt with exception
status ISCSI_LOGIN_STATUS_NO_RESOURCES in the event of a failure.
Signed-off-by: NBenjamin Wang <cpwang2009@gmail.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a long-standing bug with SCSI overflow handling
where se_cmd->data_length was incorrectly being re-assigned to
the larger CDB extracted allocation length, resulting in a number
of fabric level errors that would end up causing a session reset
in most cases.  So instead now:

 - Only re-assign se_cmd->data_length durining UNDERFLOW (to use the
   smaller value)
 - Use existing se_cmd->data_length for OVERFLOW (to use the smaller
   value)

This fix has been tested with the following CDB to generate an
SCSI overflow:

  sg_raw -r512 /dev/sdc 28 0 0 0 0 0 0 0 9 0

Tested using iscsi-target, tcm_qla2xxx, loopback and tcm_vhost fabric
ports.  Here is a bit more detail on each case:

 - iscsi-target: Bug with open-iscsi with overflow, sg_raw returns
                 -3584 bytes of data.
 - tcm_qla2xxx: Working as expected, returnins 512 bytes of data
 - loopback: sg_raw returns CHECK_CONDITION, from overflow rejection
             in transport_generic_map_mem_to_cmd()
 - tcm_vhost: Same as loopback
Reported-by: NRoland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This was originally for helping fabrics to determine overflow/underflow
status, and has been superceeded by SCF_OVERFLOW_BIT + SCF_UNDERFLOW_BIT.
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Use rcu_dereference_protected in order to prevent lockdep
complaint. Sequel of the patch 863555be

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NDenis Efremov <yefremov.denis@gmail.com>
Acked-by: NMark D. Rustad <mark.d.rustad@intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a regression bug with the handling of zero-length
data CDBs within transport_generic_new_cmd() code.  The bug was introduced
with the following commit as part of the single task conversion work:

  commit 4101f0a8
  Author: Christoph Hellwig <hch@infradead.org>
  Date:   Tue Apr 24 00:25:03 2012 -0400

      target: always allocate a single task

where the zero-length check for SCF_SCSI_DATA_SG_IO_CDB was incorrectly
changed to SCF_SCSI_CONTROL_SG_IO_CDB because of the seperate comment
in transport_generic_new_cmd() wrt to control CDBs zero-length handling
introduced in:

  commit 91ec1d35
  Author: Nicholas Bellinger <nab@linux-iscsi.org>
  Date:   Fri Jan 13 12:01:34 2012 -0800

      target: Add workaround for zero-length control CDB handling

So go ahead and change transport_generic_new_cmd() to handle control+data
zero-length CDBs in the same manner for this special case.

Tested with iscsi-target + loopback fabric port LUNs on 3.6-rc0 code.

This patch will also need to be picked up for 3.5-stable.

(hch: Add proper comment in transport_generic_new_cmd)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a regression bug in pscsi_transport_complete() callback
code where *pt was being NULL dereferenced during REPORT_LUNS handling,
that was introduced with the spc/sbc refactoring in:

commit 1fd032ee
Author: Christoph Hellwig <hch@infradead.org>
Date:   Sun May 20 11:59:15 2012 -0400

    target: move code for CDB emulation

As this is a special case for pscsi_parse_cdb() to call spc_parse_cdb() to
allow TCM to handle REPORT_LUN emulation, pscsi_plugin_task will have not
been allocated..

So now in pscsi_transport_complete() just check for existence of *pt and
return for this special case.
Reported-by: NAlex Elsayed <eternaleye+usenet@gmail.com>
Cc: Alex Elsayed <eternaleye+usenet@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

I am hitting this bug when the target is low in memory that fails the
alloc_page() for the newly submitted command. This is a sort of off-by-one
bug causing NULL pointer dereference in __free_page() since 'i' here is
really the counter of total pages that have been successfully allocated here.
Signed-off-by: NYi Zou <yi.zou@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Open-FCoE.org <devel@open-fcoe.org>
Cc: stable@vger.kernel.org
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Stop doing a pile of work related to debugging messages when
the ft_debug_logging flag is not set. Use unlikely to add the
check in a way that the check can be inlined without inlining the
whole thing.
Signed-off-by: NMark Rustad <mark.d.rustad@intel.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>