From: Amelie Delaunay Date: Tue, 27 Jun 2017 15:45:20 +0000 (+0200) Subject: spi: stm32: fix potential dereference null return value X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=7b821a6485c943edc752a94260a29116237f9153;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git spi: stm32: fix potential dereference null return value This patch fixes the usage of rx_dma_desc and tx_dma_desc pointers returned by dmaengine_prep_slave_sg, which can be null. Detected by CoverityScan, CID#1446587 ("Dereference null return value") Reported-by: Colin Ian King Signed-off-by: Amelie Delaunay Signed-off-by: Mark Brown --- diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 8a6bff379b21..75644bcd938b 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -775,9 +775,6 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, xfer->rx_sg.nents, rx_dma_conf.direction, DMA_PREP_INTERRUPT); - - rx_dma_desc->callback = stm32_spi_dma_cb; - rx_dma_desc->callback_param = spi; } tx_dma_desc = NULL; @@ -790,11 +787,6 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, xfer->tx_sg.nents, tx_dma_conf.direction, DMA_PREP_INTERRUPT); - - if (spi->cur_comm == SPI_SIMPLEX_TX) { - tx_dma_desc->callback = stm32_spi_dma_cb; - tx_dma_desc->callback_param = spi; - } } if ((spi->tx_buf && !tx_dma_desc) || @@ -802,6 +794,9 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, goto dma_desc_error; if (rx_dma_desc) { + rx_dma_desc->callback = stm32_spi_dma_cb; + rx_dma_desc->callback_param = spi; + if (dma_submit_error(dmaengine_submit(rx_dma_desc))) { dev_err(spi->dev, "Rx DMA submit failed\n"); goto dma_desc_error; @@ -811,6 +806,11 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi, } if (tx_dma_desc) { + if (spi->cur_comm == SPI_SIMPLEX_TX) { + tx_dma_desc->callback = stm32_spi_dma_cb; + tx_dma_desc->callback_param = spi; + } + if (dma_submit_error(dmaengine_submit(tx_dma_desc))) { dev_err(spi->dev, "Tx DMA submit failed\n"); goto dma_submit_error;