Re: FAILED: patch "[PATCH] [media] serial_ir: ensure we're ready to receive interrupts" failed to apply to 4.10-stable tree

[Sean Young <sean@mess.org>]

On Wed, Mar 15, 2017 at 03:31:04PM +0800, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 4.10-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
> 
> thanks,
> 
> greg k-h
> 
> ------------------ original commit in Linus's tree ------------------
> 
> >From 0265634eb9e04a16ae99941c320718c38eb865e0 Mon Sep 17 00:00:00 2001
> From: Sean Young <sean@mess.org>
> Date: Sat, 25 Feb 2017 08:28:16 -0300
> Subject: [PATCH] [media] serial_ir: ensure we're ready to receive interrupts
> 
> When the interrupt requested with devm_request_irq(), serial_ir.rcdev
> is still null so will cause null deference if the irq handler is called
> early on.
> 
> Also ensure that timeout_timer is setup.
> 
> Link: http://lkml.kernel.org/r/CA+55aFxsh2uF8gi5sN_guY3Z+tiLv7LpJYKBw+y8vqLzp+TsnQ@mail.gmail.com
> 
> [mchehab@s-opensource.com: moved serial_ir_probe() back to its original place]
> 
> Cc: <stable@vger.kernel.org> # 4.10
> Signed-off-by: Sean Young <sean@mess.org>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
> 

Here is the patch against v4.10.3, tested. 

>From 37aa6b3cb0a044e9dc0ce5e97ff2df09a10ae354 Mon Sep 17 00:00:00 2001
From: Sean Young <sean@mess.org>
Date: Sat, 25 Feb 2017 08:28:16 -0300
Subject: [PATCH] [media] serial_ir: ensure we're ready to receive interrupts

When the interrupt requested with devm_request_irq(), serial_ir.rcdev
is still null so will cause null dereference if the irq handler is called
early on.

Link: http://lkml.kernel.org/r/CA+55aFxsh2uF8gi5sN_guY3Z+tiLv7LpJYKBw+y8vqLzp+TsnQ@mail.gmail.com

[mchehab@s-opensource.com: moved serial_ir_probe() back to its original place]

Cc: <stable@vger.kernel.org> # 4.10
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
---
 drivers/media/rc/serial_ir.c | 115 ++++++++++++++++++++++---------------------
 1 file changed, 58 insertions(+), 57 deletions(-)

diff --git a/drivers/media/rc/serial_ir.c b/drivers/media/rc/serial_ir.c
index 436bd58..62f8d10 100644
--- a/drivers/media/rc/serial_ir.c
+++ b/drivers/media/rc/serial_ir.c
@@ -471,10 +471,65 @@ static int hardware_init_port(void)
 	return 0;
 }
 
+/* Needed by serial_ir_probe() */
+static int serial_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
+			unsigned int count);
+static int serial_ir_tx_duty_cycle(struct rc_dev *dev, u32 cycle);
+static int serial_ir_tx_carrier(struct rc_dev *dev, u32 carrier);
+static int serial_ir_open(struct rc_dev *rcdev);
+static void serial_ir_close(struct rc_dev *rcdev);
+
 static int serial_ir_probe(struct platform_device *dev)
 {
+	struct rc_dev *rcdev;
 	int i, nlow, nhigh, result;
 
+	rcdev = devm_rc_allocate_device(&dev->dev);
+	if (!rcdev)
+		return -ENOMEM;
+
+	if (hardware[type].send_pulse && hardware[type].send_space)
+		rcdev->tx_ir = serial_ir_tx;
+	if (hardware[type].set_send_carrier)
+		rcdev->s_tx_carrier = serial_ir_tx_carrier;
+	if (hardware[type].set_duty_cycle)
+		rcdev->s_tx_duty_cycle = serial_ir_tx_duty_cycle;
+
+	switch (type) {
+	case IR_HOMEBREW:
+		rcdev->input_name = "Serial IR type home-brew";
+		break;
+	case IR_IRDEO:
+		rcdev->input_name = "Serial IR type IRdeo";
+		break;
+	case IR_IRDEO_REMOTE:
+		rcdev->input_name = "Serial IR type IRdeo remote";
+		break;
+	case IR_ANIMAX:
+		rcdev->input_name = "Serial IR type AnimaX";
+		break;
+	case IR_IGOR:
+		rcdev->input_name = "Serial IR type IgorPlug";
+		break;
+	}
+
+	rcdev->input_phys = KBUILD_MODNAME "/input0";
+	rcdev->input_id.bustype = BUS_HOST;
+	rcdev->input_id.vendor = 0x0001;
+	rcdev->input_id.product = 0x0001;
+	rcdev->input_id.version = 0x0100;
+	rcdev->open = serial_ir_open;
+	rcdev->close = serial_ir_close;
+	rcdev->dev.parent = &serial_ir.pdev->dev;
+	rcdev->driver_type = RC_DRIVER_IR_RAW;
+	rcdev->allowed_protocols = RC_BIT_ALL;
+	rcdev->driver_name = KBUILD_MODNAME;
+	rcdev->map_name = RC_MAP_RC6_MCE;
+	rcdev->timeout = IR_DEFAULT_TIMEOUT;
+	rcdev->rx_resolution = 250000;
+
+	serial_ir.rcdev = rcdev;
+
 	result = devm_request_irq(&dev->dev, irq, serial_ir_irq_handler,
 				  share_irq ? IRQF_SHARED : 0,
 				  KBUILD_MODNAME, &hardware);
@@ -533,7 +588,8 @@ static int serial_ir_probe(struct platform_device *dev)
 			 sense ? "low" : "high");
 
 	dev_dbg(&dev->dev, "Interrupt %d, port %04x obtained\n", irq, io);
-	return 0;
+
+	return devm_rc_register_device(&dev->dev, rcdev);
 }
 
 static int serial_ir_open(struct rc_dev *rcdev)
@@ -704,7 +760,6 @@ static void serial_ir_exit(void)
 
 static int __init serial_ir_init_module(void)
 {
-	struct rc_dev *rcdev;
 	int result;
 
 	switch (type) {
@@ -735,69 +790,15 @@ static int __init serial_ir_init_module(void)
 		sense = !!sense;
 
 	result = serial_ir_init();
-	if (result)
-		return result;
-
-	rcdev = devm_rc_allocate_device(&serial_ir.pdev->dev);
-	if (!rcdev) {
-		result = -ENOMEM;
-		goto serial_cleanup;
-	}
-
-	if (hardware[type].send_pulse && hardware[type].send_space)
-		rcdev->tx_ir = serial_ir_tx;
-	if (hardware[type].set_send_carrier)
-		rcdev->s_tx_carrier = serial_ir_tx_carrier;
-	if (hardware[type].set_duty_cycle)
-		rcdev->s_tx_duty_cycle = serial_ir_tx_duty_cycle;
-
-	switch (type) {
-	case IR_HOMEBREW:
-		rcdev->input_name = "Serial IR type home-brew";
-		break;
-	case IR_IRDEO:
-		rcdev->input_name = "Serial IR type IRdeo";
-		break;
-	case IR_IRDEO_REMOTE:
-		rcdev->input_name = "Serial IR type IRdeo remote";
-		break;
-	case IR_ANIMAX:
-		rcdev->input_name = "Serial IR type AnimaX";
-		break;
-	case IR_IGOR:
-		rcdev->input_name = "Serial IR type IgorPlug";
-		break;
-	}
-
-	rcdev->input_phys = KBUILD_MODNAME "/input0";
-	rcdev->input_id.bustype = BUS_HOST;
-	rcdev->input_id.vendor = 0x0001;
-	rcdev->input_id.product = 0x0001;
-	rcdev->input_id.version = 0x0100;
-	rcdev->open = serial_ir_open;
-	rcdev->close = serial_ir_close;
-	rcdev->dev.parent = &serial_ir.pdev->dev;
-	rcdev->driver_type = RC_DRIVER_IR_RAW;
-	rcdev->allowed_protocols = RC_BIT_ALL;
-	rcdev->driver_name = KBUILD_MODNAME;
-	rcdev->map_name = RC_MAP_RC6_MCE;
-	rcdev->timeout = IR_DEFAULT_TIMEOUT;
-	rcdev->rx_resolution = 250000;
-
-	serial_ir.rcdev = rcdev;
-
-	result = rc_register_device(rcdev);
-
 	if (!result)
 		return 0;
-serial_cleanup:
+
 	serial_ir_exit();
 	return result;
 }
 
 static void __exit serial_ir_exit_module(void)
 {
-	rc_unregister_device(serial_ir.rcdev);
 	serial_ir_exit();
 }
 
-- 
2.9.3