Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Luca Coelho <luca@coelho.fi>
To:     kvalo@codeaurora.org
Cc:     luca@coelho.fi, linux-wireless@vger.kernel.org
Date:   Sat, 12 Jun 2021 14:32:39 +0300
Message-Id: <iwlwifi.20210612142637.9aa4f0e3574a.I458b283f203d5f927f00be1bfbd4b8ebf11c5ae4@changeid>
In-Reply-To: <20210612113245.691117-1-luca@coelho.fi>
References: <20210612113245.691117-1-luca@coelho.fi>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Subject: [PATCH 06/12] iwlwifi: pcie: handle pcim_iomap_table() failures better
Precedence: bulk

From: Johannes Berg <johannes.berg@intel.com>

pcim_iomap_table() might return NULL, so we shouldn't unconditionally
dereference the return value by taking the [0] entry.

Handle this better by checking for NULL first, and then separately
checking if the [0] entry is NULL.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index 228baf362474..2152ee95b19e 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -3425,6 +3425,7 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev,
 	struct iwl_trans *trans;
 	int ret, addr_size;
 	const struct iwl_trans_ops *ops = &trans_ops_pcie_gen2;
+	void __iomem * const *table;
 
 	if (!cfg_trans->gen2)
 		ops = &trans_ops_pcie;
@@ -3497,9 +3498,16 @@ struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev,
 		goto out_no_pci;
 	}
 
-	trans_pcie->hw_base = pcim_iomap_table(pdev)[0];
-	if (!trans_pcie->hw_base) {
+	table = pcim_iomap_table(pdev);
+	if (!table) {
 		dev_err(&pdev->dev, "pcim_iomap_table failed\n");
+		ret = -ENOMEM;
+		goto out_no_pci;
+	}
+
+	trans_pcie->hw_base = table[0];
+	if (!trans_pcie->hw_base) {
+		dev_err(&pdev->dev, "couldn't find IO mem in first BAR\n");
 		ret = -ENODEV;
 		goto out_no_pci;
 	}
-- 
2.32.0.rc2