[PATCH 4.4 16/24] IB/mthca: fix return value of error branch in mthca_init_cq()

[Greg Kroah-Hartman]

From: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx>

[ Upstream commit 6830ff853a5764c75e56750d59d0bbb6b26f1835 ]

We return 'err' in the error branch, but this variable may be set as zero
by the above code. Fix it by setting 'err' as a negative value before we
goto the error label.

Fixes: 74c2174e7be5 ("IB uverbs: add mthca user CQ support")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Link: https://lore.kernel.org/r/1605837422-42724-1-git-send-email-wangxiongfeng2@xxxxxxxxxx
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/hw/mthca/mthca_cq.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/hw/mthca/mthca_cq.c b/drivers/infiniband/hw/mthca/mthca_cq.c
index 40ba833381557..59e1f6ea2ede9 100644
--- a/drivers/infiniband/hw/mthca/mthca_cq.c
+++ b/drivers/infiniband/hw/mthca/mthca_cq.c
@@ -811,8 +811,10 @@ int mthca_init_cq(struct mthca_dev *dev, int nent,
 	}
 
 	mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
-	if (IS_ERR(mailbox))
+	if (IS_ERR(mailbox)) {
+		err = PTR_ERR(mailbox);
 		goto err_out_arm;
+	}
 
 	cq_context = mailbox->buf;
 
@@ -854,9 +856,9 @@ int mthca_init_cq(struct mthca_dev *dev, int nent,
 	}
 
 	spin_lock_irq(&dev->cq_table.lock);
-	if (mthca_array_set(&dev->cq_table.cq,
-			    cq->cqn & (dev->limits.num_cqs - 1),
-			    cq)) {
+	err = mthca_array_set(&dev->cq_table.cq,
+			      cq->cqn & (dev->limits.num_cqs - 1), cq);
+	if (err) {
 		spin_unlock_irq(&dev->cq_table.lock);
 		goto err_out_free_mr;
 	}
-- 
2.27.0