CVE-2026-98428ALSA: usb: 6fire: Avoid embedded URBs

Official description

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb: 6fire: Avoid embedded URBs The USB 6fire driver uses URBs embedded in different structs for PCM, MIDI and communication, and this is basically a buggy implementation nowadays; since a URB is managed with a refcount, this may lead to a UAF when the URB is released asynchronously. For addressing the problem, this patch converts those embedded URBs to ones that are properly allocated via usb_alloc_urb(). The pcm_urb.packets[] is gone, as it's allocated by usb_alloc_urb(), hence it's found in urb.iso_frame_desc[] instead. The conversions are rather straightforward; each embedded struct urb is changed to a pointer, and its callers are updated accordingly. The resource for those structs are released in the common destructor functions (usb6fire_comm_free(), etc), which are called at both the init error path and the disconnect. No functional changes, only compile-tested.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/3ef9093d83ffecb8e5f6c9d5769a52d39df74f7a
• https://git.kernel.org/stable/c/8b8559aeaba2e51cfee1779b2383b085991f7d81
• https://git.kernel.org/stable/c/52a43c2d57e774489ac3fbbac06ff02f19bd9a52
• https://git.kernel.org/stable/c/999f433c09e4668412bd68ca207ae2b4af863862
• https://git.kernel.org/stable/c/d181434549b3da668110a25d743848cce9897f4e
• https://git.kernel.org/stable/c/9fe49dbc023e82dfaee7b245997d820d01742a9a