ALSA: usb: 6fire: Avoid embedded URBs

Summary

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.

Timeline

1. Oct 14, 2026, 1:27 PM UTCCVE published
2. Oct 26, 2026, 6:55 AM UTCRecord last updated

Affected versions

• Linux Linux

  From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in 3ef9093d83ffecb8e5f6c9d5769a52d39df74f7a; From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in 8b8559aeaba2e51cfee1779b2383b085991f7d81; From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in 52a43c2d57e774489ac3fbbac06ff02f19bd9a52; From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in 999f433c09e4668412bd68ca207ae2b4af863862; From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in d181434549b3da668110a25d743848cce9897f4e; From c6d43ba816d1cf1d125bfbfc938f2a28a87facf9 · fixed in 9fe49dbc023e82dfaee7b245997d820d01742a9a

• Linux Linux

  2.6.39

• KernelLinux

  fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.112; From 6.13.0 · fixed in 6.18.54; From 6.19.0 · fixed in 7.2.8

References 6