[PATCH] scsi: lpfc: Fix potential NULL pointer dereference in lpfc_nvme_fcp_io_submit

From: Gustavo A. R. Silva
Date: Mon Nov 27 2017 - 08:52:44 EST


pnvme_lport is being dereferenced before it is null checked, hence there
is a potential null pointer dereference.

Fix this by null checking pnvme_lport before it is dereferenced.

Addresses-Coverity-ID: 1423709 ("Dereference before null check")
Fixes: b7672ae681f8 ("scsi: lpfc: Fix crash in lpfc_nvme_fcp_io_submit during LIP")
Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
---
Also, I wonder if the right pointer to check at line:

if (!pnvme_rport || !freqpriv) {

is pnvme_fcreq instead of freqpriv

drivers/scsi/lpfc/lpfc_nvme.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c
index 517ae57..68cba7d 100644
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -1251,6 +1251,11 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
uint64_t start = 0;
#endif

+ if (!pnvme_lport) {
+ ret = -ENODEV;
+ goto out_fail;
+ }
+
lport = (struct lpfc_nvme_lport *)pnvme_lport->private;
vport = lport->vport;
phba = vport->phba;
@@ -1261,7 +1266,7 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
}

/* Validate pointers. */
- if (!pnvme_lport || !pnvme_rport || !freqpriv) {
+ if (!pnvme_rport || !freqpriv) {
lpfc_printf_vlog(vport, KERN_INFO, LOG_NVME_IOERR | LOG_NODE,
"6117 No Send:IO submit ptrs NULL, lport %p, "
"rport %p fcreq_priv %p\n",
--
2.7.4