Fix potential NULL pointer dereference on
'commit 4da22f1418cb ("serial: 8250_fintek: fix the mismatched IRQ mode")'We try to fix IRQ mode mismatch issue and add the following code to detect IRQ Level or Edge mode. struct irq_data *irq_data = irq_get_irq_data(uart->port.irq); bool level_mode = irqd_is_level_type(irq_data); But *irq_data had not any check and pass to irqd_is_level_type(), it may lead to potential NULL pointer dereference. Also modify detecting IRQ mode when fintek chip found. Suggested-by: Ricardo Ribalda Delgado <[email protected]> Signed-off-by: Ji-Ze Hong (Peter Hong) <[email protected]> --- drivers/tty/serial/8250/8250_fintek.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c index 737b4b3..9119d0c 100644 --- a/drivers/tty/serial/8250/8250_fintek.c +++ b/drivers/tty/serial/8250/8250_fintek.c @@ -212,8 +212,8 @@ int fintek_8250_probe(struct uart_8250_port *uart) { struct fintek_8250 *pdata; struct fintek_8250 probe_data; - struct irq_data *irq_data = irq_get_irq_data(uart->port.irq); - bool level_mode = irqd_is_level_type(irq_data); + struct irq_data *irq_data; + bool level_mode = false; /* Default to Edge/High */ if (find_base_port(&probe_data, uart->port.iobase)) return -ENODEV; @@ -226,5 +226,14 @@ int fintek_8250_probe(struct uart_8250_port *uart) uart->port.rs485_config = fintek_8250_rs485_config; uart->port.private_data = pdata; + irq_data = irq_get_irq_data(uart->port.irq); + if (irq_data) { + level_mode = irqd_is_level_type(irq_data); + } else { + dev_warn(uart->port.dev, + "%s: Can't get irq_data, set this port to Edge/High", + __func__); + } + return fintek_8250_set_irq_mode(pdata, level_mode); } -- 1.9.1
