[PATCH AUTOSEL 5.4 03/63] tty: serial: fsl_lpuart: fix the potential risk of division or modulo by zero

[PATCH AUTOSEL 5.4 03/63] tty: serial: fsl_lpuart: fix the potential risk of division or modulo by zero

[Sasha Levin]

From: Sherry Sun <sherry.sun@nxp.com>

[ Upstream commit fcb10ee27fb91b25b68d7745db9817ecea9f1038 ]

We should be very careful about the register values that will be used
for division or modulo operations, althrough the possibility that the
UARTBAUD register value is zero is very low, but we had better to deal
with the "bad data" of hardware in advance to avoid division or modulo
by zero leading to undefined kernel behavior.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20210427021226.27468-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/fsl_lpuart.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 6ad985e8dc65..b053345dfd1a 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2253,6 +2253,9 @@ lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
 
 	bd = lpuart32_read(&sport->port, UARTBAUD);
 	bd &= UARTBAUD_SBR_MASK;
+	if (!bd)
+		return;
+
 	sbr = bd;
 	uartclk = lpuart_get_baud_clk_rate(sport);
 	/*
-- 
2.30.2

[PATCH AUTOSEL 5.4 04/63] serial: 8250: of: Check for CONFIG_SERIAL_8250_BCM7271

[Sasha Levin]

From: Jim Quinlan <jim2101024@gmail.com>

[ Upstream commit f5b08386dee439c7a9e60ce0a4a4a705f3a60dff ]

Our SoC's have always had a NS16650A UART core and older SoC's would
have a compatible string of: 'compatible = ""ns16550a"' and use the
8250_of driver. Our newer SoC's have added enhancements to the base
core to add support for DMA and accurate high speed baud rates and use
this newer 8250_bcm7271 driver. The Device Tree node for our enhanced
UARTs has a compatible string of: 'compatible = "brcm,bcm7271-uart",
"ns16550a"''. With both drivers running and the link order setup so
that the 8250_bcm7217 driver is initialized before the 8250_of driver,
we should bind the 8250_bcm7271 driver to the enhanced UART, or for
upstream kernels that don't have the 8250_bcm7271 driver, we bind to
the 8250_of driver.

The problem is that when both the 8250_of and 8250_bcm7271 drivers
were running, occasionally the 8250_of driver would be bound to the
enhanced UART instead of the 8250_bcm7271 driver. This was happening
because we use SCMI based clocks which come up late in initialization
and cause probe DEFER's when the two drivers get their clocks.

Occasionally the SCMI clock would become ready between the 8250_bcm7271
probe and the 8250_of probe and the 8250_of driver would be bound. To
fix this we decided to config only our 8250_bcm7271 driver and added
"ns16665a0" to the compatible string so the driver would work on our
older system.

This commit has of_platform_serial_probe() check specifically for the
"brcm,bcm7271-uart" and whether its companion driver is enabled. If it
is the case, and the clock provider is not ready, we want to make sure
that when the 8250_bcm7271.c driver returns EPROBE_DEFER, we are not
getting the UART registered via 8250_of.c.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210423183206.3917725-1-f.fainelli@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/8250/8250_of.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 9ba31701a372..fe9cf915fdd4 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -213,6 +213,10 @@ static int of_platform_serial_probe(struct platform_device *ofdev)
 	u32 tx_threshold;
 	int ret;
 
+	if (IS_ENABLED(CONFIG_SERIAL_8250_BCM7271) &&
+	    of_device_is_compatible(ofdev->dev.of_node, "brcm,bcm7271-uart"))
+		return -ENODEV;
+
 	port_type = (unsigned long)of_device_get_match_data(&ofdev->dev);
 	if (port_type == PORT_UNKNOWN)
 		return -EINVAL;
-- 
2.30.2

[PATCH AUTOSEL 5.4 17/63] tty: serial: 8250: serial_cs: Fix a memory leak in error handling path

[Sasha Levin]

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

[ Upstream commit fad92b11047a748c996ebd6cfb164a63814eeb2e ]

In the probe function, if the final 'serial_config()' fails, 'info' is
leaking.

Add a resource handling path to free this memory.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/dc25f96b7faebf42e60fe8d02963c941cf4d8124.1621971720.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/8250/serial_cs.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/serial_cs.c b/drivers/tty/serial/8250/serial_cs.c
index c8186a05a453..271c0388e00d 100644
--- a/drivers/tty/serial/8250/serial_cs.c
+++ b/drivers/tty/serial/8250/serial_cs.c
@@ -306,6 +306,7 @@ static int serial_resume(struct pcmcia_device *link)
 static int serial_probe(struct pcmcia_device *link)
 {
 	struct serial_info *info;
+	int ret;
 
 	dev_dbg(&link->dev, "serial_attach()\n");
 
@@ -320,7 +321,15 @@ static int serial_probe(struct pcmcia_device *link)
 	if (do_sound)
 		link->config_flags |= CONF_ENABLE_SPKR;
 
-	return serial_config(link);
+	ret = serial_config(link);
+	if (ret)
+		goto free_info;
+
+	return 0;
+
+free_info:
+	kfree(info);
+	return ret;
 }
 
 static void serial_detach(struct pcmcia_device *link)
-- 
2.30.2

[PATCH AUTOSEL 5.4 30/63] serial: tty: uartlite: fix console setup

[Sasha Levin]

From: Daniel Mack <daniel@zonque.org>

[ Upstream commit d157fca711ad42e75efef3444c83d2e1a17be27a ]

Remove the hack to assign the global console_port variable at probe time.
This assumption that cons->index is -1 is wrong for systems that specify
'console=' in the cmdline (or 'stdout-path' in dts). Hence, on such system
the actual console assignment is ignored, and the first UART that happens
to be probed is used as console instead.

Move the logic to console_setup() and map the console to the correct port
through the array of available ports instead.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20210528133321.1859346-1-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/uartlite.c | 27 ++++++---------------------
 1 file changed, 6 insertions(+), 21 deletions(-)

diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index 06e79c11141d..56066d93a65b 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -508,21 +508,23 @@ static void ulite_console_write(struct console *co, const char *s,
 
 static int ulite_console_setup(struct console *co, char *options)
 {
-	struct uart_port *port;
+	struct uart_port *port = NULL;
 	int baud = 9600;
 	int bits = 8;
 	int parity = 'n';
 	int flow = 'n';
 
-
-	port = console_port;
+	if (co->index >= 0 && co->index < ULITE_NR_UARTS)
+		port = ulite_ports + co->index;
 
 	/* Has the device been initialized yet? */
-	if (!port->mapbase) {
+	if (!port || !port->mapbase) {
 		pr_debug("console on ttyUL%i not present\n", co->index);
 		return -ENODEV;
 	}
 
+	console_port = port;
+
 	/* not initialized yet? */
 	if (!port->membase) {
 		if (ulite_request_port(port))
@@ -658,17 +660,6 @@ static int ulite_assign(struct device *dev, int id, u32 base, int irq,
 
 	dev_set_drvdata(dev, port);
 
-#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
-	/*
-	 * If console hasn't been found yet try to assign this port
-	 * because it is required to be assigned for console setup function.
-	 * If register_console() don't assign value, then console_port pointer
-	 * is cleanup.
-	 */
-	if (ulite_uart_driver.cons->index == -1)
-		console_port = port;
-#endif
-
 	/* Register the port */
 	rc = uart_add_one_port(&ulite_uart_driver, port);
 	if (rc) {
@@ -678,12 +669,6 @@ static int ulite_assign(struct device *dev, int id, u32 base, int irq,
 		return rc;
 	}
 
-#ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
-	/* This is not port which is used for console that's why clean it up */
-	if (ulite_uart_driver.cons->index == -1)
-		console_port = NULL;
-#endif
-
 	return 0;
 }
 
-- 
2.30.2