[PATCH v5 1/4] spi: pxa2xx: Validate the correctness of the SSP type

From: Andy Shevchenko
Date: Fri Oct 21 2022 - 15:00:27 EST


Currently we blindly apply the SSP type value from any source of the
information. Increase robustness by validating the value before use.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/spi/spi-pxa2xx.c | 6 ++++--
include/linux/pxa2xx_ssp.h | 1 +
2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index c9f6a3fbe62f..93be7e8ef884 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1460,7 +1460,7 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
struct resource *res;
struct pci_dev *pcidev = dev_is_pci(parent) ? to_pci_dev(parent) : NULL;
const struct pci_device_id *pcidev_id = NULL;
- enum pxa_ssp_type type;
+ enum pxa_ssp_type type = SSP_UNDEFINED;
const void *match;
int status;
u64 uid;
@@ -1473,7 +1473,9 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
type = (enum pxa_ssp_type)match;
else if (pcidev_id)
type = (enum pxa_ssp_type)pcidev_id->driver_data;
- else
+
+ /* Validate the SSP type correctness */
+ if (!(type > SSP_UNDEFINED && type < SSP_MAX))
return ERR_PTR(-EINVAL);

pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
diff --git a/include/linux/pxa2xx_ssp.h b/include/linux/pxa2xx_ssp.h
index a3fec2de512f..cd1973e6ac4b 100644
--- a/include/linux/pxa2xx_ssp.h
+++ b/include/linux/pxa2xx_ssp.h
@@ -229,6 +229,7 @@ enum pxa_ssp_type {
LPSS_SPT_SSP,
LPSS_BXT_SSP,
LPSS_CNL_SSP,
+ SSP_MAX
};

struct ssp_device {
--
2.35.1