Description
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd
In snd_usb_create_streams(), for UAC version 3 devices, the Interface Association Descriptor (IAD) is retrieved via usb_ifnum_to_if(). If this call fails, a fallback routine attempts to obtain the IAD from the next interface and sets a BADD profile. However, snd_usb_mixer_controls_badd() assumes that the IAD retrieved from usb_ifnum_to_if() is always valid, without performing a NULL check. This can lead to a NULL pointer dereference when usb_ifnum_to_if() fails to find the interface descriptor.
This patch adds a NULL pointer check after calling usb_ifnum_to_if() in snd_usb_mixer_controls_badd() to prevent the dereference.
This issue was discovered by syzkaller, which triggered the bug by sending a crafted USB device descriptor.
Metrics
No CVSS score has been published yet.
Affected software
No affected versions have been published.
Timeline
- Published
- Dec 6, 2025
- Last modified
- Oct 15, 2026
- NVD status
- Deferred