[PATCH v2] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()

[PATCH v2] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()

[Minjong Kim]

in ntrig_report_version(), hdev parameter passed from hid_probe().
sending descriptor to /dev/uhid can make hdev->dev.parent->parent to null
if hdev->dev.parent->parent is null, usb_dev has
invalid address(0xffffffffffffff58) that hid_to_usb_dev(hdev) returned
when usb_rcvctrlpipe() use usb_dev,it trigger
page fault error for address(0xffffffffffffff58)

add null check logic to ntrig_report_version()
before calling hid_to_usb_dev()

Signed-off-by: Minjong Kim <minbell.kim@samsung.com>
---
 drivers/hid/hid-ntrig.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 2738ce947434f904f32e9a1979b1681c66972ff9..0f76e241e0afb4adb38885a008a05edb24169ea9 100644
--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -144,6 +144,9 @@ static void ntrig_report_version(struct hid_device *hdev)
 	struct usb_device *usb_dev = hid_to_usb_dev(hdev);
 	unsigned char *data = kmalloc(8, GFP_KERNEL);
 
+	if (!hid_is_usb(hdev))
+		return;
+
 	if (!data)
 		goto err_free;
 

---
base-commit: 347e9f5043c89695b01e66b3ed111755afcf1911
change-id: 20250717-hid-ntrig-page-fault-fix-d13c49c86473

Best regards,
-- 
Minjong Kim <minbell.kim@samsung.com>

Re: [PATCH v2] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()

[Benjamin Tissoires]

On Wed, 13 Aug 2025 19:30:22 +0900, Minjong Kim wrote:
> in ntrig_report_version(), hdev parameter passed from hid_probe().
> sending descriptor to /dev/uhid can make hdev->dev.parent->parent to null
> if hdev->dev.parent->parent is null, usb_dev has
> invalid address(0xffffffffffffff58) that hid_to_usb_dev(hdev) returned
> when usb_rcvctrlpipe() use usb_dev,it trigger
> page fault error for address(0xffffffffffffff58)
> 
> [...]

Applied to hid/hid.git (for-6.17/upstream-fixes), thanks!

[1/1] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()
      https://git.kernel.org/hid/hid/c/185c926283da

Cheers,
-- 
Benjamin Tissoires <bentiss@kernel.org>

Re: [PATCH v2] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()

[Benjamin Tissoires]

On Aug 13 2025, Minjong Kim wrote:
> On Tue, Aug 12, 2025 at 02:46:24PM +0200, Jiri Kosina wrote:
> > 
> > I know that mixing declarations and code is fine these days, but we 
> > haven't been progressive enough to switch to that coding style in HID 
> > subsystem yet :) Would you be willing to move it below the declarations?
> >  
> 
> From 75e52defd4b2fd138285c5ad953942e2e6cf2fbb Mon Sep 17 00:00:00 2001
> From: Minjong Kim <minbell.kim@samsung.com>
> Date: Thu, 17 Jul 2025 14:37:47 +0900
> Subject: [PATCH v2] HID: hid-ntrig: fix unable to handle page fault in
>  ntrig_report_version()
> 
> in ntrig_report_version(), hdev parameter passed from hid_probe().
> sending descriptor to /dev/uhid can make hdev->dev.parent->parent to null
> if hdev->dev.parent->parent is null, usb_dev has
> invalid address(0xffffffffffffff58) that hid_to_usb_dev(hdev) returned
> when usb_rcvctrlpipe() use usb_dev,it trigger
> page fault error for address(0xffffffffffffff58)
> 
> add null check logic to ntrig_report_version()
> before calling hid_to_usb_dev()
> 
> Signed-off-by: Minjong Kim <minbell.kim@samsung.com>
> ---
>  drivers/hid/hid-ntrig.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
> index 2738ce947434..fa948d9e236c 100644
> --- a/drivers/hid/hid-ntrig.c
> +++ b/drivers/hid/hid-ntrig.c
> @@ -144,6 +144,9 @@ static void ntrig_report_version(struct hid_device *hdev)
>  	struct usb_device *usb_dev = hid_to_usb_dev(hdev);
>  	unsigned char *data = kmalloc(8, GFP_KERNEL);
> 
> +	if (!hdev->dev.parent->parent)

Why simply not use if(!hid_is_usb(hdev)) instead?

Cheers,
Benjamin

> +		return;
> +
>  	if (!data)
>  		goto err_free;
> 
> --
> 2.34.1
> 
> I move it below the declarations.
> 
> Best regards,
> 

Re: [PATCH v2] HID: hid-ntrig: fix unable to handle page fault in ntrig_report_version()

[Minjong Kim]

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On Tue, Aug 12, 2025 at 02:46:24PM +0200, Jiri Kosina wrote:
> 
> I know that mixing declarations and code is fine these days, but we 
> haven't been progressive enough to switch to that coding style in HID 
> subsystem yet :) Would you be willing to move it below the declarations?
>  

From 75e52defd4b2fd138285c5ad953942e2e6cf2fbb Mon Sep 17 00:00:00 2001
From: Minjong Kim <minbell.kim@samsung.com>
Date: Thu, 17 Jul 2025 14:37:47 +0900
Subject: [PATCH v2] HID: hid-ntrig: fix unable to handle page fault in
 ntrig_report_version()

in ntrig_report_version(), hdev parameter passed from hid_probe().
sending descriptor to /dev/uhid can make hdev->dev.parent->parent to null
if hdev->dev.parent->parent is null, usb_dev has
invalid address(0xffffffffffffff58) that hid_to_usb_dev(hdev) returned
when usb_rcvctrlpipe() use usb_dev,it trigger
page fault error for address(0xffffffffffffff58)

add null check logic to ntrig_report_version()
before calling hid_to_usb_dev()

Signed-off-by: Minjong Kim <minbell.kim@samsung.com>
---
 drivers/hid/hid-ntrig.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/hid/hid-ntrig.c b/drivers/hid/hid-ntrig.c
index 2738ce947434..fa948d9e236c 100644
--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c
@@ -144,6 +144,9 @@ static void ntrig_report_version(struct hid_device *hdev)
 	struct usb_device *usb_dev = hid_to_usb_dev(hdev);
 	unsigned char *data = kmalloc(8, GFP_KERNEL);

+	if (!hdev->dev.parent->parent)
+		return;
+
 	if (!data)
 		goto err_free;

--
2.34.1

I move it below the declarations.

Best regards,


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