CVE-2026-31754
Description
In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: gadget: fix state inconsistency on gadget init failure
When cdns3_gadget_start() fails, the DRD hardware is left in gadget mode
while software state remains INACTIVE, creating hardware/software state
inconsistency.
When switching to host mode via sysfs:
echo host > /sys/class/usb_role/13180000.usb-role-switch/role
The role state is not set to CDNS_ROLE_STATE_ACTIVE due to the error,
so cdns_role_stop() skips cleanup because state is still INACTIVE.
This violates the DRD controller design specification (Figure22),
which requires returning to idle state before switching roles.
This leads to a synchronous external abort in xhci_gen_setup() when
setting up the host controller:
[ 516.440698] configfs-gadget 13180000.usb: failed to start g1: -19
[ 516.442035] cdns-usb3 13180000.usb: Failed to add gadget
[ 516.443278] cdns-usb3 13180000.usb: set role 2 has failed
...
[ 1301.375722] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller
[ 1301.377716] Internal error: synchronous external abort: 96000010 [#1] PREEMPT SMP
[ 1301.382485] pc : xhci_gen_setup+0xa4/0x408
[ 1301.393391] backtrace:
...
xhci_gen_setup+0xa4/0x408 <-- CRASH
xhci_plat_setup+0x44/0x58
usb_add_hcd+0x284/0x678
...
cdns_role_set+0x9c/0xbc <-- Role switch
Fix by calling cdns_drd_gadget_off() in the error path to properly
clean up the DRD gadget state.
EPSS (Exploit Prediction Scoring System)
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.
Single Data Point
Only one EPSS measurement is available for this CVE. Trend analysis requires multiple data points over time.