iio: adc: ad7923: Fix buffer overflow for tx_buf and ring_xfer

The AD7923 was updated to support devices with 8 channels, but the size
of tx_buf and ring_xfer was not increased accordingly, leading to a
potential buffer overflow in ad7923_update_scan_mode().

Fixes: 851644a60d20 ("iio: adc: ad7923: Add support for the ad7908/ad7918/ad7928")
Cc: stable@vger.kernel.org
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Link: https://patch.msgid.link/20241029134637.2261336-1-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/ad7923.c b/drivers/iio/adc/ad7923.c
index 0968001..acc44cb 100644 (file)
--- a/drivers/iio/adc/ad7923.c
+++ b/drivers/iio/adc/ad7923.c
@@ -48,7 +48,7 @@
 
 struct ad7923_state {
        struct spi_device               *spi;
-       struct spi_transfer             ring_xfer[5];
+       struct spi_transfer             ring_xfer[9];
        struct spi_transfer             scan_single_xfer[2];
        struct spi_message              ring_msg;
        struct spi_message              scan_single_msg;
@@ -64,7 +64,7 @@ struct ad7923_state {
         * Length = 8 channels + 4 extra for 8 byte timestamp
         */
        __be16                          rx_buf[12] __aligned(IIO_DMA_MINALIGN);
-       __be16                          tx_buf[4];
+       __be16                          tx_buf[8];
 };
 
 struct ad7923_chip_info {