What happened
In the Linux kernel, the following vulnerability has been resolved: usbip: vhci_hcd: fix NULL deref in status_show_vhci platform_get_drvdata() can return NULL if a VHCI host controller's probe failed (e.g. due to USB bus number exhaustion). status_show_vhci() checked for a NULL pdev but not for a NULL hcd returned by platform_get_drvdata(). Passing NULL to hcd_to_vhci_hcd() does not return NULL - it returns a pointer offset of 0x260, causing a NULL pointer dereference when that value is subsequently dereferenced. Add a NULL check on hcd before calling hcd_to_vhci_hcd(). Move status_show_not_ready() above status_show_vhci() to make it callable from the new error path without a forward declaration.
Affected versions
Linux: 0775a9cbc694e8c7276688be3bbd2f386167ab54 through before 046a94fdb02eb1df86c8fa4614104ff801ba3ab7 (git); 0775a9cbc694e8c7276688be3bbd2f386167ab54 through before dacd7c317ba12e035653c28a0eaaf23d91abc073 (git); 0775a9cbc694e8c7276688be3bbd2f386167ab54 through before bc150783542ba2e7c1257d1299c6f3269bdba270 (git); 4.9 Fixed: See vendor advisory.
Why it matters
Review the vendor advisory and exposure of the affected product to determine operational impact.
Detection & mitigation
- Apply vendor-provided updates or mitigations.
- Review affected product exposure and access logs.
Public PoC references
No public PoC reference has passed the current publication threshold.