linux-stable.git/drivers/target, branch v4.4.263

scsi: target: Fix XCOPY NAA identifier lookup

2021-01-17T12:55:13+00:00

[ Upstream commit 2896c93811e39d63a4d9b63ccf12a8fbc226e5e4 ]

When attempting to match EXTENDED COPY CSCD descriptors with corresponding
se_devices, target_xcopy_locate_se_dev_e4() currently iterates over LIO's
global devices list which includes all configured backstores.

This change ensures that only initiator-accessible backstores are
considered during CSCD descriptor lookup, according to the session's
se_node_acl LUN list.

To avoid LUN removal race conditions, device pinning is changed from being
configfs based to instead using the se_node_acl lun_ref.

Reference: CVE-2020-28374
Fixes: cbf031f425fd ("target: Add support for EXTENDED_COPY copy offload emulation")
Reviewed-by: Lee Duncan 
Signed-off-by: David Disseldorp 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

xcopy: loop over devices using idr helper

2021-01-17T12:55:13+00:00

[ Upstream commit 6906d008b4b06e42cad393ac25bec76fbf31fabd ]

This converts the xcopy code to use the idr helper. The next patch
will drop the g_device_list and make g_device_mutex local to the
target_core_device.c file.

Signed-off-by: Mike Christie 
Reviewed-by: Bart Van Assche 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Sasha Levin

target: use XCOPY segment descriptor CSCD IDs

2021-01-17T12:55:12+00:00

[ Upstream commit 66640d35c1e4ef3c96ba5edb3c5e2ff8ab812e7a ]

The XCOPY specification in SPC4r37 states that the XCOPY source and
destination device(s) should be derived from the copy source and copy
destination (CSCD) descriptor IDs in the XCOPY segment descriptor.

The CSCD IDs are generally (for block -> block copies), indexes into
the corresponding CSCD descriptor list, e.g.
=================================
EXTENDED COPY Header
=================================
CSCD Descriptor List
- entry 0
  + LU ID <--------------<------------------\
- entry 1                                   |
  + LU ID <______________<_____________     |
=================================      |    |
Segment Descriptor List                |    |
- segment 0                            |    |
  + src CSCD ID = 0 --------->---------+----/
  + dest CSCD ID = 1 ___________>______|
  + len
  + src lba
  + dest lba
=================================

Currently LIO completely ignores the src and dest CSCD IDs in the
Segment Descriptor List, and instead assumes that the first entry in the
CSCD list corresponds to the source, and the second to the destination.

This commit removes this assumption, by ensuring that the Segment
Descriptor List is parsed prior to processing the CSCD Descriptor List.
CSCD Descriptor List processing is modified to compare the current list
index with the previously obtained src and dest CSCD IDs.

Additionally, XCOPY requests where the src and dest CSCD IDs refer to
the CSCD Descriptor List entry can now be successfully processed.

Fixes: cbf031f ("target: Add support for EXTENDED_COPY copy offload")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191381
Signed-off-by: David Disseldorp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Bart Van Assche 
Signed-off-by: Sasha Levin

target: simplify XCOPY wwn->se_dev lookup helper

2021-01-17T12:55:12+00:00

[ Upstream commit 94aae4caacda89a1bdb7198b260f4ca3595b7ed7 ]

target_xcopy_locate_se_dev_e4() is used to locate an se_dev, based on
the WWN provided with the XCOPY request. Remove a couple of unneeded
arguments, and rely on the caller for the src/dst test.

Signed-off-by: David Disseldorp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Bart Van Assche 
Signed-off-by: Sasha Levin

target: bounds check XCOPY segment descriptor list

2021-01-17T12:55:12+00:00

[ Upstream commit af9f62c1686268c0517b289274d38f3a03bebd2a ]

Check the length of the XCOPY request segment descriptor list against
the value advertised via the MAXIMUM SEGMENT DESCRIPTOR COUNT field in
the RECEIVE COPY OPERATING PARAMETERS response.

spc4r37 6.4.3.5 states:
  If the number of segment descriptors exceeds the allowed number, the
  copy manager shall terminate the command with CHECK CONDITION status,
  with the sense key set to ILLEGAL REQUEST, and the additional sense
  code set to TOO MANY SEGMENT DESCRIPTORS.

This functionality is testable using the libiscsi
ExtendedCopy.DescrLimits test.

Signed-off-by: David Disseldorp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Bart Van Assche 
Signed-off-by: Sasha Levin

target: add XCOPY target/segment desc sense codes

2021-01-17T12:55:12+00:00

[ Upstream commit e864212078ded276bdb272b2e0ee6a979357ca8a ]

As defined in http://www.t10.org/lists/asc-num.htm. To be used during
validation of XCOPY target and segment descriptor lists.

Signed-off-by: David Disseldorp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Bart Van Assche 
Signed-off-by: Sasha Levin

scsi: target: iscsi: Fix cmd abort fabric stop race

2020-12-02T07:29:28+00:00

[ Upstream commit f36199355c64a39fe82cfddc7623d827c7e050da ]

Maurizio found a race where the abort and cmd stop paths can race as
follows:

 1. thread1 runs iscsit_release_commands_from_conn and sets
    CMD_T_FABRIC_STOP.

 2. thread2 runs iscsit_aborted_task and then does __iscsit_free_cmd. It
    then returns from the aborted_task callout and we finish
    target_handle_abort and do:

    target_handle_abort -> transport_cmd_check_stop_to_fabric ->
	lio_check_stop_free -> target_put_sess_cmd

    The cmd is now freed.

 3. thread1 now finishes iscsit_release_commands_from_conn and runs
    iscsit_free_cmd while accessing a command we just released.

In __target_check_io_state we check for CMD_T_FABRIC_STOP and set the
CMD_T_ABORTED if the driver is not cleaning up the cmd because of a session
shutdown. However, iscsit_release_commands_from_conn only sets the
CMD_T_FABRIC_STOP and does not check to see if the abort path has claimed
completion ownership of the command.

This adds a check in iscsit_release_commands_from_conn so only the abort or
fabric stop path cleanup the command.

Link: https://lore.kernel.org/r/1605318378-9269-1-git-send-email-michael.christie@oracle.com
Reported-by: Maurizio Lombardi 
Reviewed-by: Maurizio Lombardi 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: target: iscsi: Fix hang in iscsit_access_np() when getting tpg->np_login_sem

2020-09-23T06:44:25+00:00

commit ed43ffea78dcc97db3f561da834f1a49c8961e33 upstream.

The iSCSI target login thread might get stuck with the following stack:

cat /proc/`pidof iscsi_np`/stack
[<0>] down_interruptible+0x42/0x50
[<0>] iscsit_access_np+0xe3/0x167
[<0>] iscsi_target_locate_portal+0x695/0x8ac
[<0>] __iscsi_target_login_thread+0x855/0xb82
[<0>] iscsi_target_login_thread+0x2f/0x5a
[<0>] kthread+0xfa/0x130
[<0>] ret_from_fork+0x1f/0x30

This can be reproduced via the following steps:

1. Initiator A tries to log in to iqn1-tpg1 on port 3260. After finishing
   PDU exchange in the login thread and before the negotiation is finished
   the the network link goes down. At this point A has not finished login
   and tpg->np_login_sem is held.

2. Initiator B tries to log in to iqn2-tpg1 on port 3260. After finishing
   PDU exchange in the login thread the target expects to process remaining
   login PDUs in workqueue context.

3. Initiator A' tries to log in to iqn1-tpg1 on port 3260 from a new
   socket. A' will wait for tpg->np_login_sem with np->np_login_timer
   loaded to wait for at most 15 seconds. The lock is held by A so A'
   eventually times out.

4. Before A' got timeout initiator B gets negotiation failed and calls
   iscsi_target_login_drop()->iscsi_target_login_sess_out().  The
   np->np_login_timer is canceled and initiator A' will hang forever.
   Because A' is now in the login thread, no new login requests can be
   serviced.

Fix this by moving iscsi_stop_login_thread_timer() out of
iscsi_target_login_sess_out(). Also remove iscsi_np parameter from
iscsi_target_login_sess_out().

Link: https://lore.kernel.org/r/20200729130343.24976-1-houpu@bytedance.com
Cc: stable@vger.kernel.org
Reviewed-by: Mike Christie 
Signed-off-by: Hou Pu 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: target: tcmu: Fix crash on ARM during cmd completion

2020-09-03T09:19:23+00:00

[ Upstream commit 5a0c256d96f020e4771f6fd5524b80f89a2d3132 ]

If tcmu_handle_completions() has to process a padding shorter than
sizeof(struct tcmu_cmd_entry), the current call to
tcmu_flush_dcache_range() with sizeof(struct tcmu_cmd_entry) as length
param is wrong and causes crashes on e.g. ARM, because
tcmu_flush_dcache_range() in this case calls
flush_dcache_page(vmalloc_to_page(start)); with start being an invalid
address above the end of the vmalloc'ed area.

The fix is to use the minimum of remaining ring space and sizeof(struct
tcmu_cmd_entry) as the length param.

The patch was tested on kernel 4.19.118.

See https://bugzilla.kernel.org/show_bug.cgi?id=208045#c10

Link: https://lore.kernel.org/r/20200629093756.8947-1-bstroesser@ts.fujitsu.com
Tested-by: JiangYu 
Acked-by: Mike Christie 
Signed-off-by: Bodo Stroesser 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

target: Fix a memory leak in target_dev_lba_map_store()

2020-05-10T08:26:14+00:00

commit f0a8afecb29ad0005e7e946228a0ef5422058b85 upstream.

strsep() modifies its first argument. Make the pointer passed to kfree()
match the return value of kmalloc().

Fixes: 229d4f112fd6 (commit "target_core_alua: Referrals configfs integration")
Signed-off-by: Bart Van Assche 
Cc: Hannes Reinecke 
Cc: Christoph Hellwig 
Cc: Andy Grover 
Cc: Sagi Grimberg 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman