From: Karen Dombroski <karen.dombroski@xxxxxxxxxxxxxxxxxx> [ Upstream commit 6d5ff8e632a4f2389c331e5554cd1c2a9a28c7aa ] When the number of bytes for the op is greater than one, the read could run off the end of the function stack and cause a crash. This patch restores the behaviour of safely reading out of the original opcode location. Signed-off-by: Karen Dombroski <karen.dombroski@xxxxxxxxxxxxxxxxxx> Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210429053802.17650-3-amit.kumar-mahapatra@xxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/spi/spi-zynq-qspi.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-zynq-qspi.c b/drivers/spi/spi-zynq-qspi.c index 5d8a5ee62fa2..2765289028fa 100644 --- a/drivers/spi/spi-zynq-qspi.c +++ b/drivers/spi/spi-zynq-qspi.c @@ -528,18 +528,17 @@ static int zynq_qspi_exec_mem_op(struct spi_mem *mem, struct zynq_qspi *xqspi = spi_controller_get_devdata(mem->spi->master); int err = 0, i; u8 *tmpbuf; - u8 opcode = op->cmd.opcode; dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n", - opcode, op->cmd.buswidth, op->addr.buswidth, + op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, op->dummy.buswidth, op->data.buswidth); zynq_qspi_chipselect(mem->spi, true); zynq_qspi_config_op(xqspi, mem->spi); - if (op->cmd.nbytes) { + if (op->cmd.opcode) { reinit_completion(&xqspi->data_completion); - xqspi->txbuf = &opcode; + xqspi->txbuf = (u8 *)&op->cmd.opcode; xqspi->rxbuf = NULL; xqspi->tx_bytes = op->cmd.nbytes; xqspi->rx_bytes = op->cmd.nbytes; -- 2.30.2
