[PATCH] scsi: elx: libefc: potential use after free in efc_nport_vport_del()

[Dan Carpenter]

The kref_put() function will call nport->release if the refcount drops
to zero.  The nport->release release function is _efc_nport_free() which
frees "nport".  But then we dereference "nport" on the next line which
is a use after free.  Re-order these lines to avoid the use after free.

Fixes: fcd427303eb9 ("scsi: elx: libefc: SLI and FC PORT state machine interfaces")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
>From static analysis.  Untested.  But it seems low risk.
---
 drivers/scsi/elx/libefc/efc_nport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/elx/libefc/efc_nport.c b/drivers/scsi/elx/libefc/efc_nport.c
index 2e83a667901f..1a7437f4328e 100644
--- a/drivers/scsi/elx/libefc/efc_nport.c
+++ b/drivers/scsi/elx/libefc/efc_nport.c
@@ -705,9 +705,9 @@ efc_nport_vport_del(struct efc *efc, struct efc_domain *domain,
 	spin_lock_irqsave(&efc->lock, flags);
 	list_for_each_entry(nport, &domain->nport_list, list_entry) {
 		if (nport->wwpn == wwpn && nport->wwnn == wwnn) {
-			kref_put(&nport->ref, nport->release);
 			/* Shutdown this NPORT */
 			efc_sm_post_event(&nport->sm, EFC_EVT_SHUTDOWN, NULL);
+			kref_put(&nport->ref, nport->release);
 			break;
 		}
 	}
-- 
2.43.0