From: Quanyang Wang quanyang.wang@windriver.com
[ Upstream commit a2c5bedb2d55dd27c642c7b9fb6886d7ad7bdb58 ]
When handling op->addr, it is using the buffer "tmpbuf" which has been freed. This will trigger a use-after-free KASAN warning. Let's use temporary variables to store op->addr.val and op->cmd.opcode to fix this issue.
Fixes: 1c26372e5aa9 ("spi: spi-zynqmp-gqspi: Update driver to use spi-mem framework") Signed-off-by: Quanyang Wang quanyang.wang@windriver.com Link: https://lore.kernel.org/r/20210416004652.2975446-5-quanyang.wang@windriver.c... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-zynqmp-gqspi.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c index d6ac8fe145a1..2a0be16b2eb0 100644 --- a/drivers/spi/spi-zynqmp-gqspi.c +++ b/drivers/spi/spi-zynqmp-gqspi.c @@ -926,8 +926,9 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem, struct zynqmp_qspi *xqspi = spi_controller_get_devdata (mem->spi->master); int err = 0, i; - u8 *tmpbuf; u32 genfifoentry = 0; + u16 opcode = op->cmd.opcode; + u64 opaddr;
dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n", op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, @@ -940,14 +941,8 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem, genfifoentry |= xqspi->genfifobus;
if (op->cmd.opcode) { - tmpbuf = kzalloc(op->cmd.nbytes, GFP_KERNEL | GFP_DMA); - if (!tmpbuf) { - mutex_unlock(&xqspi->op_lock); - return -ENOMEM; - } - tmpbuf[0] = op->cmd.opcode; reinit_completion(&xqspi->data_completion); - xqspi->txbuf = tmpbuf; + xqspi->txbuf = &opcode; xqspi->rxbuf = NULL; xqspi->bytes_to_transfer = op->cmd.nbytes; xqspi->bytes_to_receive = 0; @@ -961,13 +956,12 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem, if (!wait_for_completion_timeout (&xqspi->data_completion, msecs_to_jiffies(1000))) { err = -ETIMEDOUT; - kfree(tmpbuf); goto return_err; } - kfree(tmpbuf); }
if (op->addr.nbytes) { + xqspi->txbuf = &opaddr; for (i = 0; i < op->addr.nbytes; i++) { *(((u8 *)xqspi->txbuf) + i) = op->addr.val >> (8 * (op->addr.nbytes - i - 1));