[PATCH 4.19 057/306] RDMA/bnxt_re: Avoid NULL check after accessing the pointer

From: Greg Kroah-Hartman
Date: Wed Nov 27 2019 - 16:27:36 EST


From: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>

[ Upstream commit eae4ad1b0c9a77ef0cbac212d58d46976eaacfc1 ]

This is reported by smatch check. rcfw->creq_bar_reg_iomem is accessed in
bnxt_qplib_rcfw_stop_irq and this variable check afterwards doesn't make
sense. Also, rcfw->creq_bar_reg_iomem will never be NULL. So Removing
this check.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Fixes: 6e04b1035689 ("RDMA/bnxt_re: Fix broken RoCE driver due to recent L2 driver changes")
Signed-off-by: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/hw/bnxt_re/qplib_rcfw.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
index 6637df77d2365..8b3b5fdc19bbb 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
@@ -614,13 +614,8 @@ void bnxt_qplib_disable_rcfw_channel(struct bnxt_qplib_rcfw *rcfw)

bnxt_qplib_rcfw_stop_irq(rcfw, true);

- if (rcfw->cmdq_bar_reg_iomem)
- iounmap(rcfw->cmdq_bar_reg_iomem);
- rcfw->cmdq_bar_reg_iomem = NULL;
-
- if (rcfw->creq_bar_reg_iomem)
- iounmap(rcfw->creq_bar_reg_iomem);
- rcfw->creq_bar_reg_iomem = NULL;
+ iounmap(rcfw->cmdq_bar_reg_iomem);
+ iounmap(rcfw->creq_bar_reg_iomem);

indx = find_first_bit(rcfw->cmdq_bitmap, rcfw->bmap_size);
if (indx != rcfw->bmap_size)
@@ -629,6 +624,8 @@ void bnxt_qplib_disable_rcfw_channel(struct bnxt_qplib_rcfw *rcfw)
kfree(rcfw->cmdq_bitmap);
rcfw->bmap_size = 0;

+ rcfw->cmdq_bar_reg_iomem = NULL;
+ rcfw->creq_bar_reg_iomem = NULL;
rcfw->aeq_handler = NULL;
rcfw->vector = 0;
}
@@ -714,6 +711,8 @@ int bnxt_qplib_enable_rcfw_channel(struct pci_dev *pdev,
dev_err(&rcfw->pdev->dev,
"QPLIB: CREQ BAR region %d mapping failed",
rcfw->creq_bar_reg);
+ iounmap(rcfw->cmdq_bar_reg_iomem);
+ rcfw->cmdq_bar_reg_iomem = NULL;
return -ENOMEM;
}
rcfw->creq_qp_event_processed = 0;
--
2.20.1