linux-stable.git/include/scsi, branch linux-5.12.y

scsi: iscsi: Fix conn use after free during resets

2021-07-20T14:02:07+00:00

[ Upstream commit ec29d0ac29be366450a7faffbcf8cba3a6a3b506 ]

If we haven't done a unbind target call we can race where
iscsi_conn_teardown wakes up the EH thread and then frees the conn while
those threads are still accessing the conn ehwait.

We can only do one TMF per session so this just moves the TMF fields from
the conn to the session. We can then rely on the
iscsi_session_teardown->iscsi_remove_session->__iscsi_unbind_session call
to remove the target and it's devices, and know after that point there is
no device or scsi-ml callout trying to access the session.

Link: https://lore.kernel.org/r/20210525181821.7617-14-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: iscsi: Add iscsi_cls_conn refcount helpers

2021-07-20T14:02:07+00:00

[ Upstream commit b1d19e8c92cfb0ded180ef3376c20e130414e067 ]

There are a couple places where we could free the iscsi_cls_conn while it's
still in use. This adds some helpers to get/put a refcount on the struct
and converts an exiting user. Subsequent commits will then use the helpers
to fix 2 bugs in the eh code.

Link: https://lore.kernel.org/r/20210525181821.7617-11-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: fc: Correct RHBA attributes length

2021-07-14T15:00:29+00:00

commit 40445fd2c9fa427297acdfcc2c573ff10493f209 upstream.

As per the FC-GS-5 specification, attribute lengths of node_name and
manufacturer should in range of "4 to 64 Bytes" only.

Link: https://lore.kernel.org/r/20210603101404.7841-2-jhasan@marvell.com
Fixes: e721eb0616f6 ("scsi: scsi_transport_fc: Match HBA Attribute Length with HBAAPI V2.0 definitions")
CC: stable@vger.kernel.org
Reviewed-by: Himanshu Madhani 
Signed-off-by: Javed Hasan 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman

scsi: iscsi: Fix in-kernel conn failure handling

2021-07-14T15:00:17+00:00

[ Upstream commit 23d6fefbb3f6b1cc29794427588b470ed06ff64e ]

Commit 0ab710458da1 ("scsi: iscsi: Perform connection failure entirely in
kernel space") has the following regressions/bugs that this patch fixes:

1. It can return cmds to upper layers like dm-multipath where that can
retry them. After they are successful the fs/app can send new I/O to the
same sectors, but we've left the cmds running in FW or in the net layer.
We need to be calling ep_disconnect if userspace is not up.

This patch only fixes the issue for offload drivers. iscsi_tcp will be
fixed in separate commit because it doesn't have a ep_disconnect call.

2. The drivers that implement ep_disconnect expect that it's called before
conn_stop. Besides crashes, if the cleanup_task callout is called before
ep_disconnect it might free up driver/card resources for session1 then they
could be allocated for session2. But because the driver's ep_disconnect is
not called it has not cleaned up the firmware so the card is still using
the resources for the original cmd.

3. The stop_conn_work_fn can run after userspace has done its recovery and
we are happily using the session. We will then end up with various bugs
depending on what is going on at the time.

We may also run stop_conn_work_fn late after userspace has called stop_conn
and ep_disconnect and is now going to call start/bind conn. If
stop_conn_work_fn runs after bind but before start, we would leave the conn
in a unbound but sort of started state where IO might be allowed even
though the drivers have been set in a state where they no longer expect
I/O.

4. Returning -EAGAIN in iscsi_if_destroy_conn if we haven't yet run the in
kernel stop_conn function is breaking userspace. We should have been doing
this for the caller.

Link: https://lore.kernel.org/r/20210525181821.7617-8-michael.christie@oracle.com
Fixes: 0ab710458da1 ("scsi: iscsi: Perform connection failure entirely in kernel space")
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: iscsi: Rel ref after iscsi_lookup_endpoint()

2021-07-14T15:00:16+00:00

[ Upstream commit 9e5fe1700896c85040943fdc0d3fee0dd3e0d36f ]

Subsequent commits allow the kernel to do ep_disconnect. In that case we
will have to get a proper refcount on the ep so one thread does not delete
it from under another.

Link: https://lore.kernel.org/r/20210525181821.7617-7-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: iscsi: Stop queueing during ep_disconnect

2021-07-14T15:00:16+00:00

[ Upstream commit 891e2639deae721dc43764a44fa255890dc34313 ]

During ep_disconnect we have been doing iscsi_suspend_tx/queue to block new
I/O but every driver except cxgbi and iscsi_tcp can still get I/O from
__iscsi_conn_send_pdu() if we haven't called iscsi_conn_failure() before
ep_disconnect. This could happen if we were terminating the session, and
the logout timed out before it was even sent to libiscsi.

Fix the issue by adding a helper which reverses the bind_conn call that
allows new I/O to be queued. Drivers implementing ep_disconnect can use this
to make sure new I/O is not queued to them when handling the disconnect.

Link: https://lore.kernel.org/r/20210525181821.7617-3-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

Fix misc new gcc warnings

2021-05-12T06:39:59+00:00

commit e7c6e405e171fb33990a12ecfd14e6500d9e5cf2 upstream.

It seems like Fedora 34 ends up enabling a few new gcc warnings, notably
"-Wstringop-overread" and "-Warray-parameter".

Both of them cause what seem to be valid warnings in the kernel, where
we have array size mismatches in function arguments (that are no longer
just silently converted to a pointer to element, but actually checked).

This fixes most of the trivial ones, by making the function declaration
match the function definition, and in the case of intel_pm.c, removing
the over-specified array size from the argument declaration.

At least one 'stringop-overread' warning remains in the i915 driver, but
that one doesn't have the same obvious trivial fix, and may or may not
actually be indicative of a bug.

[ It was a mistake to upgrade one of my machines to Fedora 34 while
  being busy with the merge window, but if this is the extent of the
  compiler upgrade problems, things are better than usual    - Linus ]

Signed-off-by: Linus Torvalds 
Cc: Andrey Zhizhikin 
Signed-off-by: Greg Kroah-Hartman

scsi: iscsi: Fix race condition between login and sync thread

2021-03-30T01:17:45+00:00

A kernel panic was observed due to a timing issue between the sync thread
and the initiator processing a login response from the target. The session
reopen can be invoked both from the session sync thread when iscsid
restarts and from iscsid through the error handler. Before the initiator
receives the response to a login, another reopen request can be sent from
the error handler/sync session. When the initial login response is
subsequently processed, the connection has been closed and the socket has
been released.

To fix this a new connection state, ISCSI_CONN_BOUND, is added:

 - Set the connection state value to ISCSI_CONN_DOWN upon
   iscsi_if_ep_disconnect() and iscsi_if_stop_conn()

 - Set the connection state to the newly created value ISCSI_CONN_BOUND
   after bind connection (transport->bind_conn())

 - In iscsi_set_param(), return -ENOTCONN if the connection state is not
   either ISCSI_CONN_BOUND or ISCSI_CONN_UP

Link: https://lore.kernel.org/r/20210325093248.284678-1-gulam.mohamed@oracle.com
Reviewed-by: Mike Christie 
Signed-off-by: Gulam Mohamed 
Signed-off-by: Martin K. Petersen 

index 91074fd97f64..f4bf62b007a0 100644

scsi: libiscsi: Add helper to calculate max SCSI cmds per session

2021-02-09T03:39:04+00:00

This patch just breaks out the code that calculates the number of SCSI cmds
that will be used for a SCSI session. It also adds a check that we don't go
over the host's can_queue value.

Link: https://lore.kernel.org/r/20210207044608.27585-6-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: libiscsi: Drop taskqueuelock

2021-02-09T03:39:03+00:00

The purpose of the taskqueuelock was to handle the issue where a bad target
decides to send a R2T and before its data has been sent decides to send a
cmd response to complete the cmd. The following patches fix up the
frwd/back locks so they are taken from the queue/xmit (frwd) and completion
(back) paths again. To get there this patch removes the taskqueuelock which
for iSCSI xmit wq based drivers was taken in the queue, xmit and completion
paths.

Instead of the lock, we just make sure we have a ref to the task when we
queue a R2T, and then we always remove the task from the requeue list in
the xmit path or the forced cleanup paths.

Link: https://lore.kernel.org/r/20210207044608.27585-3-michael.christie@oracle.com
Reviewed-by: Lee Duncan 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen