On 14.04.2021 17:25, Krzysztof Kozlowski wrote:
On 14/04/2021 17:12, Krzysztof Kozlowski wrote:The driver can be matched by legacy platform way or OF-device matching. In the first case, of_match_node() can return NULL, which immediately would be dereferenced to get the match data. Addresses-Coverity: Dereference null return value Fixes: cd1b00eb24b0 ("mmc: sdhci-s3c: Add device tree support") Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
-#ifdef CONFIG_OF -static const struct of_device_id sdhci_s3c_dt_match[]; -#endif - static inline struct sdhci_s3c_drv_data *sdhci_s3c_get_driver_data( struct platform_device *pdev) { #ifdef CONFIG_OF - if (pdev->dev.of_node) { - const struct of_device_id *match; - match = of_match_node(sdhci_s3c_dt_match, pdev->dev.of_node);Now I have second thoughts whether NULL pointer can actually happen. If device is matched via platform/board files, maybe the pdev->dev.of_node will be NULL thus skipping this branch? Could there be a case where device is matched via platform_device_id() (which has different name than compatible!) and (pdev->dev.of_node) is still assigned? Maybe in case of out of tree DTS?
That seems unlikely, the platform device would need to be initialized via board file and then its of_node assigned somehow. It doesn't make much sense to me. We either use board file or dtb to instantiate devices.
Anyway, the patch makes the code simpler/smaller, so I still think it is reasonable. Just the severity of issue is questionable...
Yes, the patch looks good. Similar cleanups are already done in most of the s3c/s5p/exynos drivers. -- Thanks, Sylwester
