Unverified Commit 6d5ff8e6 authored by Karen Dombroski's avatar Karen Dombroski Committed by Mark Brown
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spi: spi-zynq-qspi: Fix stack violation bug 



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: default avatarKaren Dombroski <karen.dombroski@marsbioimaging.com>
Signed-off-by: default avatarAmit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
Link: https://lore.kernel.org/r/20210429053802.17650-3-amit.kumar-mahapatra@xilinx.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 121271f0

drivers/spi/spi-zynq-qspi.c

+3 −4
Original line number Diff line number Diff line
@@ -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;