spi: s3c64xx: avoid possible negative array index

The platform id is used as an index into the fifo_lvl_mask array.
Platforms can come with a negative device ID, PLATFORM_DEVID_NONE (-1),
thus we risked a negative array index. Catch such cases and fail to
probe.

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20240207120431.2766269-6-tudor.ambarus@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index f6048345022d6a316edea13bea02ec43b806201d..87b7203f9b1f17614cbac53de30836891f77630d 100644 (file)
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1189,6 +1189,9 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
                                             "Failed to get alias id\n");
                sdd->port_id = ret;
        } else {
+               if (pdev->id < 0)
+                       return dev_err_probe(&pdev->dev, -EINVAL,
+                                            "Negative platform ID is not allowed\n");
                sdd->port_id = pdev->id;
        }