[PATCH V2 2/2] serial: sprd: Fix DMA buffer leak issue

From: Chunyan Zhang
Date: Wed Jul 12 2023 - 23:20:10 EST


Release DMA buffer when _probe() returns failure to avoid memory leak,
also set rx_dma.virt to NULL after being freed.

Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support")
Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
---
V2:
- Added Baolin's Reviewed-by;
- Add setting rx_dma.virt to NULL after being freed.
---
drivers/tty/serial/sprd_serial.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index 11de338a6122..29d89751b3bb 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -364,7 +364,7 @@ static void sprd_rx_free_buf(struct sprd_uart_port *sp)
if (sp->rx_dma.virt)
dma_free_coherent(sp->port.dev, SPRD_UART_RX_SIZE,
sp->rx_dma.virt, sp->rx_dma.phys_addr);
-
+ sp->rx_dma.virt = NULL;
}

static int sprd_rx_dma_config(struct uart_port *port, u32 burst)
@@ -1203,7 +1203,7 @@ static int sprd_probe(struct platform_device *pdev)
ret = uart_register_driver(&sprd_uart_driver);
if (ret < 0) {
pr_err("Failed to register SPRD-UART driver\n");
- return ret;
+ goto free_rx_buf;
}
}
sprd_ports_num++;
@@ -1222,7 +1222,8 @@ static int sprd_probe(struct platform_device *pdev)
sprd_port[index] = NULL;
sprd_ports_num--;
uart_unregister_driver(&sprd_uart_driver);
- sprd_remove(pdev);
+free_rx_buf:
+ sprd_rx_free_buf(sport);
return ret;
}

--
2.41.0