iio: adc: tsc2046: add sanity check to avoid to big allocations

To avoid problematic devicetree configurations. Set allocation limit with error message and suggestion on what can be done to solve this issue. Signed-off-by: Oleksij Rempel <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Cameron <[email protected]>
josf · Jan 23, 2022 · 576434f · 576434f
1 parent b617693
commit 576434f
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/drivers/iio/adc/ti-tsc2046.c b/drivers/iio/adc/ti-tsc2046.c
@@ -679,6 +679,12 @@ static int tsc2046_adc_setup_spi_msg(struct tsc2046_adc_priv *priv)
 	for (ch_idx = 0; ch_idx < priv->dcfg->num_channels; ch_idx++)
 		size += tsc2046_adc_group_set_layout(priv, ch_idx, ch_idx);
 
+	if (size > PAGE_SIZE) {
+		dev_err(&priv->spi->dev,
+			"Calculated scan buffer is too big. Try to reduce spi-max-frequency, settling-time-us or oversampling-ratio\n");
+		return -ENOSPC;
+	}
+
 	priv->tx = devm_kzalloc(&priv->spi->dev, size, GFP_KERNEL);
 	if (!priv->tx)
 		return -ENOMEM;