[PATCH v2 10/27] hpsa: fix hpsa_adjust_hpsa_scsi_table

Don Brace
2015-11-04T21:54:48Z

Fix a NULL pointer issue in the driver when devices are removed
during a reset.

Signed-off-by: Don Brace <don.brace@pmcs.com>
---
drivers/scsi/hpsa.c | 16 ++++++++++++++++
drivers/scsi/hpsa.h | 1 +
2 files changed, 17 insertions(+)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index ae9968b..382cb5d 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -1663,6 +1663,15 @@ static void adjust_hpsa_scsi_table(struct ctlr_info *h,
int nadded, nremoved;
struct Scsi_Host *sh = NULL;

+ /*
+ * A reset can cause a device status to change
+ * re-schedule the scan to see what happened.
+ */
+ if (h->reset_in_progress) {
+ h->drv_req_rescan = 1;
+ return;
+ }
+
added = kzalloc(sizeof(*added) * HPSA_MAX_DEVICES, GFP_KERNEL);
removed = kzalloc(sizeof(*removed) * HPSA_MAX_DEVICES, GFP_KERNEL);

@@ -1771,6 +1780,10 @@ static void adjust_hpsa_scsi_table(struct ctlr_info *h,
goto free_and_out;

sh = h->scsi_host;
+ if (sh == NULL) {
+ dev_warn(&h->pdev->dev, "%s: scsi_host is null\n", __func__);
+ goto free_and_out;
+ }
/* Notify scsi mid layer of any removed devices */
for (i = 0; i < nremoved; i++) {
if (removed[i] == NULL)
@@ -5234,12 +5247,15 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd)

hpsa_show_dev_msg(KERN_WARNING, h, dev, "resetting");

+ h->reset_in_progress = 1;
+
/* send a reset to the SCSI LUN which the command was sent to */
rc = hpsa_do_reset(h, dev, dev->scsi3addr, HPSA_RESET_TYPE_LUN,
DEFAULT_REPLY_QUEUE);
snprintf(msg, sizeof(msg), "reset %s",
rc == 0 ? "completed successfully" : "failed");
hpsa_show_dev_msg(KERN_WARNING, h, dev, msg);
+ h->reset_in_progress = 0;
return rc == 0 ? SUCCESS : FAILED;
}

diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h
index b173c0e..dc113c1a 100644
--- a/drivers/scsi/hpsa.h
+++ b/drivers/scsi/hpsa.h
@@ -271,6 +271,7 @@ struct ctlr_info {
wait_queue_head_t abort_cmd_wait_queue;
wait_queue_head_t event_sync_wait_queue;
struct mutex reset_mutex;
+ u8 reset_in_progress;
};

struct offline_device_entry {