Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "This is the final round of mostly small fixes in our initial submit.

  It's mostly minor fixes and driver updates. The only change of note is
  adding a virt_boundary_mask to the SCSI host and host template to
  parametrise this for NVMe devices instead of having them do a call in
  slave_alloc. It's a fairly straightforward conversion except in the
  two NVMe handling drivers that didn't set it who now have a virtual
  infinity parameter added"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (24 commits)
  scsi: megaraid_sas: set an unlimited max_segment_size
  scsi: mpt3sas: set an unlimited max_segment_size for SAS 3.0 HBAs
  scsi: IB/srp: set virt_boundary_mask in the scsi host
  scsi: IB/iser: set virt_boundary_mask in the scsi host
  scsi: storvsc: set virt_boundary_mask in the scsi host template
  scsi: ufshcd: set max_segment_size in the scsi host template
  scsi: core: take the DMA max mapping size into account
  scsi: core: add a host / host template field for the virt boundary
  scsi: core: Fix race on creating sense cache
  scsi: sd_zbc: Fix compilation warning
  scsi: libfc: fix null pointer dereference on a null lport
  scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitialized
  scsi: zfcp: fix request object use-after-free in send path causing wrong traces
  scsi: zfcp: fix request object use-after-free in send path causing seqno errors
  scsi: megaraid_sas: Update driver version to 07.710.50.00
  scsi: megaraid_sas: Add module parameter for FW Async event logging
  scsi: megaraid_sas: Enable msix_load_balance for Invader and later controllers
  scsi: megaraid_sas: Fix calculation of target ID
  scsi: lpfc: reduce stack size with CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE
  scsi: devinfo: BLIST_TRY_VPD_PAGES for SanDisk Cruzer Blade
  ...

2 files changed, 55 insertions, 7 deletions

diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index e8fc28dba8df..96f0d34e9459 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kthread.h>
+#include <linux/bug.h>
 #include "zfcp_ext.h"
 #include "zfcp_reqlist.h"
 
@@ -217,6 +218,12 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(enum zfcp_erp_act_type need,
 	struct zfcp_erp_action *erp_action;
 	struct zfcp_scsi_dev *zfcp_sdev;
 
+	if (WARN_ON_ONCE(need != ZFCP_ERP_ACTION_REOPEN_LUN &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT_FORCED &&
+			 need != ZFCP_ERP_ACTION_REOPEN_ADAPTER))
+		return NULL;
+
 	switch (need) {
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		zfcp_sdev = sdev_to_zfcp(sdev);
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index d94496ee6883..296bbc3c4606 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/blktrace_api.h>
+#include <linux/types.h>
 #include <linux/slab.h>
 #include <scsi/fc/fc_els.h>
 #include "zfcp_ext.h"
@@ -741,6 +742,7 @@ static struct zfcp_fsf_req *zfcp_fsf_req_create(struct zfcp_qdio *qdio,
 
 static int zfcp_fsf_req_send(struct zfcp_fsf_req *req)
 {
+	const bool is_srb = zfcp_fsf_req_is_status_read_buffer(req);
 	struct zfcp_adapter *adapter = req->adapter;
 	struct zfcp_qdio *qdio = adapter->qdio;
 	int req_id = req->req_id;
@@ -757,8 +759,20 @@ static int zfcp_fsf_req_send(struct zfcp_fsf_req *req)
 		return -EIO;
 	}
 
+	/*
+	 * NOTE: DO NOT TOUCH ASYNC req PAST THIS POINT.
+	 *	 ONLY TOUCH SYNC req AGAIN ON req->completion.
+	 *
+	 * The request might complete and be freed concurrently at any point
+	 * now. This is not protected by the QDIO-lock (req_q_lock). So any
+	 * uncontrolled access after this might result in an use-after-free bug.
+	 * Only if the request doesn't have ZFCP_STATUS_FSFREQ_CLEANUP set, and
+	 * when it is completed via req->completion, is it safe to use req
+	 * again.
+	 */
+
 	/* Don't increase for unsolicited status */
-	if (!zfcp_fsf_req_is_status_read_buffer(req))
+	if (!is_srb)
 		adapter->fsf_req_seq_no++;
 	adapter->req_no++;
 
@@ -805,6 +819,7 @@ int zfcp_fsf_status_read(struct zfcp_qdio *qdio)
 	retval = zfcp_fsf_req_send(req);
 	if (retval)
 		goto failed_req_send;
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 
 	goto out;
 
@@ -914,8 +929,10 @@ struct zfcp_fsf_req *zfcp_fsf_abort_fcp_cmnd(struct scsi_cmnd *scmnd)
 	req->qtcb->bottom.support.req_handle = (u64) old_req_id;
 
 	zfcp_fsf_start_timer(req, ZFCP_FSF_SCSI_ER_TIMEOUT);
-	if (!zfcp_fsf_req_send(req))
+	if (!zfcp_fsf_req_send(req)) {
+		/* NOTE: DO NOT TOUCH req, UNTIL IT COMPLETES! */
 		goto out;
+	}
 
 out_error_free:
 	zfcp_fsf_req_free(req);
@@ -1098,6 +1115,7 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port,
 	ret = zfcp_fsf_req_send(req);
 	if (ret)
 		goto failed_send;
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 
 	goto out;
 
@@ -1198,6 +1216,7 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id,
 	ret = zfcp_fsf_req_send(req);
 	if (ret)
 		goto failed_send;
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 
 	goto out;
 
@@ -1243,6 +1262,7 @@ int zfcp_fsf_exchange_config_data(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1279,8 +1299,10 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_qdio *qdio,
 	zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
 	retval = zfcp_fsf_req_send(req);
 	spin_unlock_irq(&qdio->req_q_lock);
-	if (!retval)
+	if (!retval) {
+		/* NOTE: ONLY TOUCH SYNC req AGAIN ON req->completion. */
 		wait_for_completion(&req->completion);
+	}
 
 	zfcp_fsf_req_free(req);
 	return retval;
@@ -1330,6 +1352,7 @@ int zfcp_fsf_exchange_port_data(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1372,8 +1395,10 @@ int zfcp_fsf_exchange_port_data_sync(struct zfcp_qdio *qdio,
 	retval = zfcp_fsf_req_send(req);
 	spin_unlock_irq(&qdio->req_q_lock);
 
-	if (!retval)
+	if (!retval) {
+		/* NOTE: ONLY TOUCH SYNC req AGAIN ON req->completion. */
 		wait_for_completion(&req->completion);
+	}
 
 	zfcp_fsf_req_free(req);
 
@@ -1493,6 +1518,7 @@ int zfcp_fsf_open_port(struct zfcp_erp_action *erp_action)
 		erp_action->fsf_req_id = 0;
 		put_device(&port->dev);
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1557,6 +1583,7 @@ int zfcp_fsf_close_port(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1600,6 +1627,7 @@ int zfcp_fsf_open_wka_port(struct zfcp_fc_wka_port *wka_port)
 {
 	struct zfcp_qdio *qdio = wka_port->adapter->qdio;
 	struct zfcp_fsf_req *req;
+	unsigned long req_id = 0;
 	int retval = -EIO;
 
 	spin_lock_irq(&qdio->req_q_lock);
@@ -1622,14 +1650,17 @@ int zfcp_fsf_open_wka_port(struct zfcp_fc_wka_port *wka_port)
 	hton24(req->qtcb->bottom.support.d_id, wka_port->d_id);
 	req->data = wka_port;
 
+	req_id = req->req_id;
+
 	zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
 	retval = zfcp_fsf_req_send(req);
 	if (retval)
 		zfcp_fsf_req_free(req);
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	if (!retval)
-		zfcp_dbf_rec_run_wka("fsowp_1", wka_port, req->req_id);
+		zfcp_dbf_rec_run_wka("fsowp_1", wka_port, req_id);
 	return retval;
 }
 
@@ -1655,6 +1686,7 @@ int zfcp_fsf_close_wka_port(struct zfcp_fc_wka_port *wka_port)
 {
 	struct zfcp_qdio *qdio = wka_port->adapter->qdio;
 	struct zfcp_fsf_req *req;
+	unsigned long req_id = 0;
 	int retval = -EIO;
 
 	spin_lock_irq(&qdio->req_q_lock);
@@ -1677,14 +1709,17 @@ int zfcp_fsf_close_wka_port(struct zfcp_fc_wka_port *wka_port)
 	req->data = wka_port;
 	req->qtcb->header.port_handle = wka_port->handle;
 
+	req_id = req->req_id;
+
 	zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
 	retval = zfcp_fsf_req_send(req);
 	if (retval)
 		zfcp_fsf_req_free(req);
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	if (!retval)
-		zfcp_dbf_rec_run_wka("fscwp_1", wka_port, req->req_id);
+		zfcp_dbf_rec_run_wka("fscwp_1", wka_port, req_id);
 	return retval;
 }
 
@@ -1776,6 +1811,7 @@ int zfcp_fsf_close_physical_port(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1899,6 +1935,7 @@ int zfcp_fsf_open_lun(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -1987,6 +2024,7 @@ int zfcp_fsf_close_lun(struct zfcp_erp_action *erp_action)
 		zfcp_fsf_req_free(req);
 		erp_action->fsf_req_id = 0;
 	}
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 out:
 	spin_unlock_irq(&qdio->req_q_lock);
 	return retval;
@@ -2299,6 +2337,7 @@ int zfcp_fsf_fcp_cmnd(struct scsi_cmnd *scsi_cmnd)
 	retval = zfcp_fsf_req_send(req);
 	if (unlikely(retval))
 		goto failed_scsi_cmnd;
+	/* NOTE: DO NOT TOUCH req PAST THIS POINT! */
 
 	goto out;
 
@@ -2373,8 +2412,10 @@ struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *sdev,
 	zfcp_fc_fcp_tm(fcp_cmnd, sdev, tm_flags);
 
 	zfcp_fsf_start_timer(req, ZFCP_FSF_SCSI_ER_TIMEOUT);
-	if (!zfcp_fsf_req_send(req))
+	if (!zfcp_fsf_req_send(req)) {
+		/* NOTE: DO NOT TOUCH req, UNTIL IT COMPLETES! */
 		goto out;
+	}
 
 	zfcp_fsf_req_free(req);
 	req = NULL;