Since the fw_event deletes itself from the list, cleanup_queue() can
walk onto garbage pointers or walk off into freed memory.
This refactors the code in _scsih_fw_event_cleanup_queue() to not
iterate over the fw_event_list without a lock.
Signed-off-by: Calvin Owens <calvinow...@fb.com>
---
drivers/scsi/mpt2sas/mpt2sas_scsih.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 8d8c814..f504e28 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -2939,6 +2939,23 @@ mpt2sas_port_enable_complete(struct MPT2SAS_ADAPTER *ioc)
fw_event_work_put(fw_event);
}
+static struct fw_event_work *dequeue_next_fw_event(struct MPT2SAS_ADAPTER *ioc)
+{
+ unsigned long flags;
+ struct fw_event_work *fw_event = NULL;
+
+ spin_lock_irqsave(&ioc->fw_event_lock, flags);
+ if (!list_empty(&ioc->fw_event_list)) {
+ fw_event = list_first_entry(&ioc->fw_event_list,
+ struct fw_event_work, list);
+ list_del_init(&fw_event->list);
+ fw_event_work_get(fw_event);
+ }
+ spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
+
+ return fw_event;
+}
+
/**
* _scsih_fw_event_cleanup_queue - cleanup event queue
* @ioc: per adapter object
@@ -2951,17 +2968,18 @@ mpt2sas_port_enable_complete(struct MPT2SAS_ADAPTER
*ioc)
static void
_scsih_fw_event_cleanup_queue(struct MPT2SAS_ADAPTER *ioc)
{
- struct fw_event_work *fw_event, *next;
+ struct fw_event_work *fw_event;
if (list_empty(&ioc->fw_event_list) ||
!ioc->firmware_event_thread || in_interrupt())
return;
- list_for_each_entry_safe(fw_event, next, &ioc->fw_event_list, list) {
+ while ((fw_event = dequeue_next_fw_event(ioc))) {
if (cancel_delayed_work_sync(&fw_event->delayed_work)) {
_scsih_fw_event_free(ioc, fw_event);
continue;
}
+ fw_event_work_put(fw_event);
}
}
--
1.8.1
--
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