[PATCH v2] serial: pch_uart: potential dereference of null pointer
From: Jiasheng Jiang <hidden>
Date: 2021-12-16 12:51:46
Also in:
lkml
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
The return value of dma_alloc_coherent() needs to be checked.
To avoid dereference of null pointer in case of the failure of alloc.
Fixes: ab4382d27412 ("tty: move drivers/serial/ to drivers/tty/serial/")
Signed-off-by: Jiasheng Jiang <redacted>
---
Changelog:
v1 -> v2
*Change 1. Add the dev_err when dma_alloc_coherent failed.
---
drivers/tty/serial/pch_uart.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f0351e6f0ef6..d19ed7da24fa 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c@@ -745,6 +745,14 @@ static void pch_request_dma(struct uart_port *port) /* Get Consistent memory for DMA */ priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize, &priv->rx_buf_dma, GFP_KERNEL); + if (!priv->rx_buf_virt) { + dev_err(priv->port.dev, "%s:dma_alloc_coherent FAILS(Rx)\n", + __func__); + dma_release_channel(priv->chan_tx); + priv->chan_tx = NULL; + return; + } + priv->chan_rx = chan; }
--
2.25.1