[06/12] iwlwifi: pcie: handle pcim_iomap_table() failures better

Commit Message

Luca Coelho June 12, 2021, 11:32 a.m. UTC

From: Johannes Berg <[e-mail]>

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 <[e-mail]>
Signed-off-by: Luca Coelho <[e-mail]>
---
 drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

Patch

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;
 	}