CVE-2026-93214 usb: gadget: f_tcm: fix deadlock in usbg_make_tpg()
A local attacker with USB gadget configuration access can trigger a kernel deadlock, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-93214?
CVE-2026-93214 is a denial of service vulnerability in Linux, published on 24 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_tcm: fix deadlock in usbg_make_tpg()
usbg_make_tpg() held dep_lock while calling configfs_depend_item_unlocked(), which acquires the configfs root inode lock when operating across subsystems. This creates a circular lock dependency with configfs_rmdir():
dep_lock -> configfs root inode lock -> su_mutex -> dep_lock
In usbg_make_tpg(), dep_lock only serialized the read of opts->ready, which is a monotonic flag that transitions from false to true exactly once (in tcm_set_name()) and never reverts. Remove dep_lock from usbg_make_tpg() entirely and use READ_ONCE/WRITE_ONCE to access opts->ready locklessly instead.
Which versions are affected by CVE-2026-93214?
How do I fix CVE-2026-93214?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-93214 being exploited?
There is no known exploitation of CVE-2026-93214 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-93214, DEBIAN-CVE-2026-93214, GHSA-wwm2-chq9-c6mx, UBUNTU-CVE-2026-93214.