CVE-2021-47436

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

usb: musb: dsps: Fix the probe error path

Commit 7c75bde329d7 ("usb: musb: musb_dsps: request_irq() after

initializing musb") has inverted the calls to

dsps_setup_optional_vbus_irq() and dsps_create_musb_pdev() without

updating correctly the error path. dsps_create_musb_pdev() allocates and

registers a new platform device which must be unregistered and freed

with platform_device_unregister(), and this is missing upon

dsps_setup_optional_vbus_irq() error.

While on the master branch it seems not to trigger any issue, I observed

a kernel crash because of a NULL pointer dereference with a v5.10.70

stable kernel where the patch mentioned above was backported. With this

kernel version, -EPROBE_DEFER is returned the first time

dsps_setup_optional_vbus_irq() is called which triggers the probe to

error out without unregistering the platform device. Unfortunately, on

the Beagle Bone Black Wireless, the platform device still l

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References