kernel/linux.git/include/scsi/scsi_transport_iscsi.h, branch v6.1.165

scsi: iscsi: Fix multiple iSCSI session unbind events sent to userspace

2023-02-01T07:34:27+00:00

[ Upstream commit a3be19b91ea7121d388084e8c07f5b1b982eb40c ] It was observed that the kernel would potentially send ISCSI_KEVENT_UNBIND_SESSION multiple times. Introduce 'target_state' in iscsi_cls_session() to make sure session will send only one unbind session event. This introduces a regression wrt. the issue fixed in commit 13e60d3ba287 ("scsi: iscsi: Report unbind session event when the target has been removed"). If iscsid dies for any reason after sending an unbind session to kernel, once iscsid is restarted, the kernel's ISCSI_KEVENT_UNBIND_SESSION event is lost and userspace is then unable to logout. However, the session is actually in invalid state (its target_id is INVALID) so iscsid should not sync this session during restart. Consequently we need to check the session's target state during iscsid restart. If session is in unbound state, do not sync this session and perform session teardown. This is OK because once a session is unbound, we can not recover it any more (mainly because its target id is INVALID). Signed-off-by: Wenchao Hao Link: https://lore.kernel.org/r/20221126010752.231917-1-haowenchao@huawei.com Reviewed-by: Mike Christie Reviewed-by: Wu Bo Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: iscsi: Add helper to remove a session from the kernel

2022-06-22T01:14:54+00:00

During qedi shutdown we need to stop the iSCSI layer from sending new nops as pings and from responding to target ones and make sure there is no running connection cleanups. Commit d1f2ce77638d ("scsi: qedi: Fix host removal with running sessions") converted the driver to use the libicsi helper to drive session removal, so the above issues could be handled. The problem is that during system shutdown iscsid will not be running so when we try to remove the root session we will hang waiting for userspace to reply. Add a helper that will drive the destruction of sessions like these during system shutdown. Link: https://lore.kernel.org/r/20220616222738.5722-5-michael.christie@oracle.com Tested-by: Nilesh Javali Reviewed-by: Nilesh Javali Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Make iscsi_unregister_transport() return void

2022-06-17T02:11:18+00:00

This function always returns 0. We can make it return void to simplify the code. Also, no caller ever checks the return value of this function. Link: https://lore.kernel.org/r/20220616080210.18531-1-mgurtovoy@nvidia.com Reviewed-by: Mike Christie Signed-off-by: Max Gurtovoy Signed-off-by: Martin K. Petersen

scsi: iscsi: Fix conn cleanup and stop race during iscsid restart

2022-04-12T02:09:34+00:00

If iscsid is doing a stop_conn at the same time the kernel is starting error recovery we can hit a race that allows the cleanup work to run on a valid connection. In the race, iscsi_if_stop_conn sees the cleanup bit set, but it calls flush_work on the clean_work before iscsi_conn_error_event has queued it. The flush then returns before the queueing and so the cleanup_work can run later and disconnect/stop a conn while it's in a connected state. The patch: Commit 0ab710458da1 ("scsi: iscsi: Perform connection failure entirely in kernel space") added the late stop_conn call bug originally, and the patch: Commit 23d6fefbb3f6 ("scsi: iscsi: Fix in-kernel conn failure handling") attempted to fix it but only fixed the normal EH case and left the above race for the iscsid restart case. For the normal EH case we don't hit the race because we only signal userspace to start recovery after we have done the queueing, so the flush will always catch the queued work or see it completed. For iscsid restart cases like boot, we can hit the race because iscsid will call down to the kernel before the kernel has signaled any error, so both code paths can be running at the same time. This adds a lock around the setting of the cleanup bit and queueing so they happen together. Link: https://lore.kernel.org/r/20220408001314.5014-6-michael.christie@oracle.com Fixes: 0ab710458da1 ("scsi: iscsi: Perform connection failure entirely in kernel space") Tested-by: Manish Rangankar Reviewed-by: Lee Duncan Reviewed-by: Chris Leech Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Release endpoint ID when its freed

2022-04-12T02:09:34+00:00

We can't release the endpoint ID until all references to the endpoint have been dropped or it could be allocated while in use. This has us use an idr instead of looping over all conns to find a free ID and then free the ID when all references have been dropped instead of when the device is only deleted. Link: https://lore.kernel.org/r/20220408001314.5014-4-michael.christie@oracle.com Tested-by: Manish Rangankar Reviewed-by: Lee Duncan Reviewed-by: Chris Leech Reviewed-by: Wu Bo Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: libiscsi: Teardown iscsi_cls_conn gracefully

2022-03-15T04:20:16+00:00

Commit 1b8d0300a3e9 ("scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown()") fixed an UAF in iscsi_conn_get_param() and introduced 2 tmp_xxx varibles. We can gracefully fix this UAF with the help of device_del(). Calling iscsi_remove_conn() at the beginning of iscsi_conn_teardown would make userspace unable to see iscsi_cls_conn. This way we we can free memory safely. Remove iscsi_destroy_conn() since it is no longer used. Link: https://lore.kernel.org/r/20220310015759.3296841-4-haowenchao@huawei.com Reviewed-by: Mike Christie Signed-off-by: Wenchao Hao Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen

scsi: libiscsi: Add iscsi_cls_conn to sysfs after initialization

2022-03-15T04:19:50+00:00

iscsi_create_conn() exposed iscsi_cls_conn to sysfs prior to initialization of iscsi_conn's dd_data. When userspace tried to access an attribute such as the connect address, a NULL pointer dereference was observed. Do not add iscsi_cls_conn to sysfs until it has been initialized. Remove iscsi_create_conn() since it is no longer used. Link: https://lore.kernel.org/r/20220310015759.3296841-3-haowenchao@huawei.com Reviewed-by: Mike Christie Signed-off-by: Wenchao Hao Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen

scsi: iscsi: Add helper functions to manage iscsi_cls_conn

2022-03-15T04:19:50+00:00

- iscsi_alloc_conn(): Allocate and initialize iscsi_cls_conn - iscsi_add_conn(): Expose iscsi_cls_conn to userspace via sysfs - iscsi_remove_conn(): Remove iscsi_cls_conn from sysfs Link: https://lore.kernel.org/r/20220310015759.3296841-2-haowenchao@huawei.com Reviewed-by: Mike Christie Signed-off-by: Wenchao Hao Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen

scsi: iscsi: ql4xxx: Use per-session workqueue for unbinding

2022-03-02T04:56:28+00:00

We currently allocate a workqueue per host and only use it for removing the target. For the session per host case we could be using this workqueue to be able to do recoveries (block, unblock, timeout handling) in parallel. To also allow offload drivers to do their session recoveries in parallel, this drops the per host workqueue and replaces it with a per session one. Link: https://lore.kernel.org/r/20220226230435.38733-5-michael.christie@oracle.com Reviewed-by: Lee Duncan Reviewed-by: Chris Leech Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Remove iscsi_scan_finished()

2022-03-02T04:56:28+00:00

qla4xxx does not use iscsi_scan_finished() anymore so remove it. Link: https://lore.kernel.org/r/20220226230435.38733-4-michael.christie@oracle.com Reviewed-by: Lee Duncan Reviewed-by: Chris Leech Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen