[PATCH 4.19 313/321] mailbox: mailbox-test: fix null pointer if no mmio

From: Greg Kroah-Hartman
Date: Tue Dec 03 2019 - 17:58:44 EST


From: Fabien Dessenne <fabien.dessenne@xxxxxx>

commit 6899b4f7c99c72968e58e502f96084f74f6e5e86 upstream.

Fix null pointer issue if resource_size is called with no ioresource.

Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
Signed-off-by: Fabien Dessenne <fabien.dessenne@xxxxxx>
Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mailbox/mailbox-test.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -363,22 +363,24 @@ static int mbox_test_probe(struct platfo

/* It's okay for MMIO to be NULL */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- size = resource_size(res);
tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
- if (PTR_ERR(tdev->tx_mmio) == -EBUSY)
+ if (PTR_ERR(tdev->tx_mmio) == -EBUSY) {
/* if reserved area in SRAM, try just ioremap */
+ size = resource_size(res);
tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
- else if (IS_ERR(tdev->tx_mmio))
+ } else if (IS_ERR(tdev->tx_mmio)) {
tdev->tx_mmio = NULL;
+ }

/* If specified, second reg entry is Rx MMIO */
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- size = resource_size(res);
tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
- if (PTR_ERR(tdev->rx_mmio) == -EBUSY)
+ if (PTR_ERR(tdev->rx_mmio) == -EBUSY) {
+ size = resource_size(res);
tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
- else if (IS_ERR(tdev->rx_mmio))
+ } else if (IS_ERR(tdev->rx_mmio)) {
tdev->rx_mmio = tdev->tx_mmio;
+ }

tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
tdev->rx_channel = mbox_test_request_channel(pdev, "rx");