FKIE_CVE-2025-68758
Vulnerability from fkie_nvd - Published: 2026-01-05 10:15 - Updated: 2026-01-19 13:16
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
backlight: led-bl: Add devlink to supplier LEDs
LED Backlight is a consumer of one or multiple LED class devices, but
devlink is currently unable to create correct supplier-producer links when
the supplier is a class device. It creates instead a link where the
supplier is the parent of the expected device.
One consequence is that removal order is not correctly enforced.
Issues happen for example with the following sections in a device tree
overlay:
// An LED driver chip
pca9632@62 {
compatible = "nxp,pca9632";
reg = <0x62>;
// ...
addon_led_pwm: led-pwm@3 {
reg = <3>;
label = "addon:led:pwm";
};
};
backlight-addon {
compatible = "led-backlight";
leds = <&addon_led_pwm>;
brightness-levels = <255>;
default-brightness-level = <255>;
};
In this example, the devlink should be created between the backlight-addon
(consumer) and the pca9632@62 (supplier). Instead it is created between the
backlight-addon (consumer) and the parent of the pca9632@62, which is
typically the I2C bus adapter.
On removal of the above overlay, the LED driver can be removed before the
backlight device, resulting in:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
Call trace:
led_put+0xe0/0x140
devm_led_release+0x6c/0x98
Another way to reproduce the bug without any device tree overlays is
unbinding the LED class device (pca9632@62) before unbinding the consumer
(backlight-addon):
echo 11-0062 >/sys/bus/i2c/drivers/leds-pca963x/unbind
echo ...backlight-dock >/sys/bus/platform/drivers/led-backlight/unbind
Fix by adding a devlink between the consuming led-backlight device and the
supplying LED device, as other drivers and subsystems do as well.
References
Impacted products
| Vendor | Product | Version |
|---|
{
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbacklight: led-bl: Add devlink to supplier LEDs\n\nLED Backlight is a consumer of one or multiple LED class devices, but\ndevlink is currently unable to create correct supplier-producer links when\nthe supplier is a class device. It creates instead a link where the\nsupplier is the parent of the expected device.\n\nOne consequence is that removal order is not correctly enforced.\n\nIssues happen for example with the following sections in a device tree\noverlay:\n\n // An LED driver chip\n pca9632@62 {\n compatible = \"nxp,pca9632\";\n reg = \u003c0x62\u003e;\n\n\t// ...\n\n addon_led_pwm: led-pwm@3 {\n reg = \u003c3\u003e;\n label = \"addon:led:pwm\";\n };\n };\n\n backlight-addon {\n compatible = \"led-backlight\";\n leds = \u003c\u0026addon_led_pwm\u003e;\n brightness-levels = \u003c255\u003e;\n default-brightness-level = \u003c255\u003e;\n };\n\nIn this example, the devlink should be created between the backlight-addon\n(consumer) and the pca9632@62 (supplier). Instead it is created between the\nbacklight-addon (consumer) and the parent of the pca9632@62, which is\ntypically the I2C bus adapter.\n\nOn removal of the above overlay, the LED driver can be removed before the\nbacklight device, resulting in:\n\n Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010\n ...\n Call trace:\n led_put+0xe0/0x140\n devm_led_release+0x6c/0x98\n\nAnother way to reproduce the bug without any device tree overlays is\nunbinding the LED class device (pca9632@62) before unbinding the consumer\n(backlight-addon):\n\n echo 11-0062 \u003e/sys/bus/i2c/drivers/leds-pca963x/unbind\n echo ...backlight-dock \u003e/sys/bus/platform/drivers/led-backlight/unbind\n\nFix by adding a devlink between the consuming led-backlight device and the\nsupplying LED device, as other drivers and subsystems do as well."
}
],
"id": "CVE-2025-68758",
"lastModified": "2026-01-19T13:16:12.037",
"metrics": {},
"published": "2026-01-05T10:15:56.897",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/08c9dc6b0f2c68e5e7c374ac4499e321e435d46c"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/0e63ea4378489e09eb5e920c8a50c10caacf563a"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/30cbe4b642745a9488a0f0d78be43afe69d7555c"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/60a24070392ec726ccfe6ad1ca7b0381c8d8f7c9"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/64739adf3eef063b8e2c72b7e919eac8c6480bf0"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9341d6698f4cfdfc374fb6944158d111ebe16a9d"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/cd01a24b3e52d6777b49c917d841f125fe9eebd0"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/e06df738a9ad8417f1c4c7cd6992cda320e9e7ca"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Awaiting Analysis"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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