From bdc095631d50f9b61ce4e933d118a6e6654c11c9 Mon Sep 17 00:00:00 2001 From: Aditya Pakki Date: Wed, 13 Mar 2019 11:55:41 -0500 Subject: [PATCH] spi : spi-topcliff-pch: Fix to handle empty DMA buffers [ Upstream commit f37d8e67f39e6d3eaf4cc5471e8a3d21209843c6 ] pch_alloc_dma_buf allocated tx, rx DMA buffers which can fail. Further, these buffers are used without a check. The patch checks for these failures and sends the error upstream. Signed-off-by: Aditya Pakki Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-topcliff-pch.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c index 97d1375..4389ab8 100644 --- a/drivers/spi/spi-topcliff-pch.c +++ b/drivers/spi/spi-topcliff-pch.c @@ -1294,18 +1294,27 @@ static void pch_free_dma_buf(struct pch_spi_board_data *board_dat, dma->rx_buf_virt, dma->rx_buf_dma); } -static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat, +static int pch_alloc_dma_buf(struct pch_spi_board_data *board_dat, struct pch_spi_data *data) { struct pch_spi_dma_ctrl *dma; + int ret; dma = &data->dma; + ret = 0; /* Get Consistent memory for Tx DMA */ dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL); + if (!dma->tx_buf_virt) + ret = -ENOMEM; + /* Get Consistent memory for Rx DMA */ dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL); + if (!dma->rx_buf_virt) + ret = -ENOMEM; + + return ret; } static int pch_spi_pd_probe(struct platform_device *plat_dev) @@ -1382,7 +1391,9 @@ static int pch_spi_pd_probe(struct platform_device *plat_dev) if (use_dma) { dev_info(&plat_dev->dev, "Use DMA for data transfers\n"); - pch_alloc_dma_buf(board_dat, data); + ret = pch_alloc_dma_buf(board_dat, data); + if (ret) + goto err_spi_register_master; } ret = spi_register_master(master); -- 2.7.4