GHSA-85H2-WVW9-QF62
Vulnerability from github – Published: 2026-09-16 12:30 – Updated: 2026-09-16 12:30In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: midi2: Fix null-pointer dereference in f_midi2_free_ep_reqs
A null-pointer dereference occurs in f_midi2_free_ep_reqs() when attempting to clean up an endpoint that was never initialized.
When configuring the MIDI 2.0 gadget via configfs and setting the block direction to SNDRV_UMP_DIR_INPUT, the initialization of the midi1_ep_out endpoint is explicitly skipped during the gadget bind phase (f_midi2_bind()). As a result, the usb_ep->card field remains NULL.
Later, when the host sets the alternate setting, f_midi2_set_alt() unconditionally stops both the IN and OUT endpoints by calling f_midi2_stop_eps(), which in turn calls f_midi2_free_ep_reqs() for both endpoints. When f_midi2_free_ep_reqs() is called for the uninitialized midi1_ep_out, it attempts to dereference usb_ep->card to determine the number of requests to free, leading to a crash.
Fix this by using usb_ep->num_reqs instead of usb_ep->card->info.num_reqs in f_midi2_free_ep_reqs(). usb_ep->num_reqs is correctly set during f_midi2_init_ep() and remains 0 if the endpoint was never initialized, safely avoiding the loop. For consistency, apply the same change to f_midi2_alloc_ep_reqs().
Oops: general protection fault, probably for non-canonical address 0xdffffc00000000ee: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000770-0x0000000000000777] ... RIP: 0010:f_midi2_free_ep_reqs drivers/usb/gadget/function/f_midi2.c:1166 [inline] RIP: 0010:f_midi2_stop_eps+0x28e/0x4d0 drivers/usb/gadget/function/f_midi2.c:1246 ... Call Trace: f_midi2_set_alt+0x11c/0xf00 drivers/usb/gadget/function/f_midi2.c:1296 composite_setup+0x1ffd/0x3480 drivers/usb/gadget/composite.c:1933 configfs_composite_setup+0xbd/0x100 drivers/usb/gadget/configfs.c:1877
{
"affected": [],
"aliases": [
"CVE-2026-90024"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-16T11:17:15Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: midi2: Fix null-pointer dereference in f_midi2_free_ep_reqs\n\nA null-pointer dereference occurs in f_midi2_free_ep_reqs() when attempting\nto clean up an endpoint that was never initialized.\n\nWhen configuring the MIDI 2.0 gadget via configfs and setting the block\ndirection to SNDRV_UMP_DIR_INPUT, the initialization of the midi1_ep_out\nendpoint is explicitly skipped during the gadget bind phase\n(f_midi2_bind()). As a result, the usb_ep-\u003ecard field remains NULL.\n\nLater, when the host sets the alternate setting, f_midi2_set_alt()\nunconditionally stops both the IN and OUT endpoints by calling\nf_midi2_stop_eps(), which in turn calls f_midi2_free_ep_reqs() for both\nendpoints. When f_midi2_free_ep_reqs() is called for the uninitialized\nmidi1_ep_out, it attempts to dereference usb_ep-\u003ecard to determine the\nnumber of requests to free, leading to a crash.\n\nFix this by using usb_ep-\u003enum_reqs instead of usb_ep-\u003ecard-\u003einfo.num_reqs\nin f_midi2_free_ep_reqs(). usb_ep-\u003enum_reqs is correctly set during\nf_midi2_init_ep() and remains 0 if the endpoint was never initialized,\nsafely avoiding the loop. For consistency, apply the same change to\nf_midi2_alloc_ep_reqs().\n\nOops: general protection fault, probably for non-canonical address\n0xdffffc00000000ee: 0000 [#1] SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000770-0x0000000000000777]\n...\nRIP: 0010:f_midi2_free_ep_reqs drivers/usb/gadget/function/f_midi2.c:1166\n[inline]\nRIP: 0010:f_midi2_stop_eps+0x28e/0x4d0\ndrivers/usb/gadget/function/f_midi2.c:1246\n...\nCall Trace:\n \u003cTASK\u003e\n f_midi2_set_alt+0x11c/0xf00 drivers/usb/gadget/function/f_midi2.c:1296\n composite_setup+0x1ffd/0x3480 drivers/usb/gadget/composite.c:1933\n configfs_composite_setup+0xbd/0x100 drivers/usb/gadget/configfs.c:1877",
"id": "GHSA-85h2-wvw9-qf62",
"modified": "2026-09-16T12:30:45Z",
"published": "2026-09-16T12:30:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90024"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4079f19a0e1ce76f1e21a398f02aca150ceaaf61"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/51ddc55c75087ac25342f6d73d3aeaf14f59bd76"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5b92f6a0c7c01efbb335d837ecdf34d38d98720f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9c3d5091e3568ed48ac4c5b08a78eb06fad0d70a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f0efaf1872949e96d213c8e910fd9517f7d7c406"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.