[PATCH 4.9 169/271] scsi: libfc: fix null pointer dereference on a null lport

From: Greg Kroah-Hartman
Date: Tue Jan 28 2020 - 09:21:46 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

[ Upstream commit 41a6bf6529edd10a6def42e3b2c34a7474bcc2f5 ]

Currently if lport is null then the null lport pointer is dereference when
printing out debug via the FC_LPORT_DB macro. Fix this by using the more
generic FC_LIBFC_DBG debug macro instead that does not use lport.

Addresses-Coverity: ("Dereference after null check")
Fixes: 7414705ea4ae ("libfc: Add runtime debugging with debug_logging module parameter")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/libfc/fc_exch.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 16ca31ad5ec0a..d0a86ef806522 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -2506,7 +2506,7 @@ void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp)

/* lport lock ? */
if (!lport || lport->state == LPORT_ST_DISABLED) {
- FC_LPORT_DBG(lport, "Receiving frames for an lport that "
+ FC_LIBFC_DBG("Receiving frames for an lport that "
"has not been initialized correctly\n");
fc_frame_free(fp);
return;
--
2.20.1