GHSA-FHP6-CW2V-3RQJ
Vulnerability from github – Published: 2026-05-01 15:30 – Updated: 2026-05-07 18:30In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: u_ether: Fix race between gether_disconnect and eth_stop
A race condition between gether_disconnect() and eth_stop() leads to a NULL pointer dereference. Specifically, if eth_stop() is triggered concurrently while gether_disconnect() is tearing down the endpoints, eth_stop() attempts to access the cleared endpoint descriptor, causing the following NPE:
Unable to handle kernel NULL pointer dereference Call trace: __dwc3_gadget_ep_enable+0x60/0x788 dwc3_gadget_ep_enable+0x70/0xe4 usb_ep_enable+0x60/0x15c eth_stop+0xb8/0x108
Because eth_stop() crashes while holding the dev->lock, the thread running gether_disconnect() fails to acquire the same lock and spins forever, resulting in a hardlockup:
Core - Debugging Information for Hardlockup core(7) Call trace: queued_spin_lock_slowpath+0x94/0x488 _raw_spin_lock+0x64/0x6c gether_disconnect+0x19c/0x1e8 ncm_set_alt+0x68/0x1a0 composite_setup+0x6a0/0xc50
The root cause is that the clearing of dev->port_usb in gether_disconnect() is delayed until the end of the function.
Move the clearing of dev->port_usb to the very beginning of gether_disconnect() while holding dev->lock. This cuts off the link immediately, ensuring eth_stop() will see dev->port_usb as NULL and safely bail out.
{
"affected": [],
"aliases": [
"CVE-2026-31728"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-01T15:16:35Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: u_ether: Fix race between gether_disconnect and eth_stop\n\nA race condition between gether_disconnect() and eth_stop() leads to a\nNULL pointer dereference. Specifically, if eth_stop() is triggered\nconcurrently while gether_disconnect() is tearing down the endpoints,\neth_stop() attempts to access the cleared endpoint descriptor, causing\nthe following NPE:\n\n Unable to handle kernel NULL pointer dereference\n Call trace:\n __dwc3_gadget_ep_enable+0x60/0x788\n dwc3_gadget_ep_enable+0x70/0xe4\n usb_ep_enable+0x60/0x15c\n eth_stop+0xb8/0x108\n\nBecause eth_stop() crashes while holding the dev-\u003elock, the thread\nrunning gether_disconnect() fails to acquire the same lock and spins\nforever, resulting in a hardlockup:\n\n Core - Debugging Information for Hardlockup core(7)\n Call trace:\n queued_spin_lock_slowpath+0x94/0x488\n _raw_spin_lock+0x64/0x6c\n gether_disconnect+0x19c/0x1e8\n ncm_set_alt+0x68/0x1a0\n composite_setup+0x6a0/0xc50\n\nThe root cause is that the clearing of dev-\u003eport_usb in\ngether_disconnect() is delayed until the end of the function.\n\nMove the clearing of dev-\u003eport_usb to the very beginning of\ngether_disconnect() while holding dev-\u003elock. This cuts off the link\nimmediately, ensuring eth_stop() will see dev-\u003eport_usb as NULL and\nsafely bail out.",
"id": "GHSA-fhp6-cw2v-3rqj",
"modified": "2026-05-07T18:30:34Z",
"published": "2026-05-01T15:30:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31728"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6ad77458637b78ec655e3da5f112c862e6690a9d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8ff689edfeceb5e3ec1623e09af2b2aa0f1098a8"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a259ba0bce3b192c04334499690372a250f7d0b1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/bbb09bb89ffa571475f66daca9482b974cd29d6a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e1e7a66584bf0aff3becb73c19fa31527889fc9e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/e1eabb072c75681f78312c484ccfffb7430f206e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f02980594deef751e42133714aee25228f1494c6"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f6813c2b2ae78def76b69e0f9d72f80e4a1c4aca"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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