diff options
| author | Fei Shao <fshao@chromium.org> | 2024-03-21 15:08:57 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2024-03-21 11:28:21 +0000 |
| commit | a20ad45008a7c82f1184dc6dee280096009ece55 (patch) | |
| tree | b8c512981fb37efb39ca9643c8d9c16b4984cbeb | |
| parent | 2ff0573e7aff5129d73ec5c3159cd84d862cb1cc (diff) | |
| download | lwn-a20ad45008a7c82f1184dc6dee280096009ece55.tar.gz lwn-a20ad45008a7c82f1184dc6dee280096009ece55.zip | |
spi: spi-mt65xx: Fix NULL pointer access in interrupt handler
The TX buffer in spi_transfer can be a NULL pointer, so the interrupt
handler may end up writing to the invalid memory and cause crashes.
Add a check to trans->tx_buf before using it.
Fixes: 1ce24864bff4 ("spi: mediatek: Only do dma for 4-byte aligned buffers")
Signed-off-by: Fei Shao <fshao@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://msgid.link/r/20240321070942.1587146-2-fshao@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | drivers/spi/spi-mt65xx.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 8d4633b353ee..e4cb22fe0075 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -788,17 +788,19 @@ static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id) mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len); mtk_spi_setup_packet(host); - cnt = mdata->xfer_len / 4; - iowrite32_rep(mdata->base + SPI_TX_DATA_REG, - trans->tx_buf + mdata->num_xfered, cnt); + if (trans->tx_buf) { + cnt = mdata->xfer_len / 4; + iowrite32_rep(mdata->base + SPI_TX_DATA_REG, + trans->tx_buf + mdata->num_xfered, cnt); - remainder = mdata->xfer_len % 4; - if (remainder > 0) { - reg_val = 0; - memcpy(®_val, - trans->tx_buf + (cnt * 4) + mdata->num_xfered, - remainder); - writel(reg_val, mdata->base + SPI_TX_DATA_REG); + remainder = mdata->xfer_len % 4; + if (remainder > 0) { + reg_val = 0; + memcpy(®_val, + trans->tx_buf + (cnt * 4) + mdata->num_xfered, + remainder); + writel(reg_val, mdata->base + SPI_TX_DATA_REG); + } } mtk_spi_enable_transfer(host); |