GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

FKIE_CVE-2026-90024

Vulnerability from fkie_nvd - Published: 2026-09-16 11:17 - Updated: 2026-09-16 11:17
Severity
Summary
In 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: <TASK> 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
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4079f19a0e1ce76f1e21a398f02aca150ceaaf61
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/51ddc55c75087ac25342f6d73d3aeaf14f59bd76
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5b92f6a0c7c01efbb335d837ecdf34d38d98720f
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9c3d5091e3568ed48ac4c5b08a78eb06fad0d70a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f0efaf1872949e96d213c8e910fd9517f7d7c406
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/gadget/function/f_midi2.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "51ddc55c75087ac25342f6d73d3aeaf14f59bd76",
              "status": "affected",
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "versionType": "git"
            },
            {
              "lessThan": "5b92f6a0c7c01efbb335d837ecdf34d38d98720f",
              "status": "affected",
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "versionType": "git"
            },
            {
              "lessThan": "9c3d5091e3568ed48ac4c5b08a78eb06fad0d70a",
              "status": "affected",
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "versionType": "git"
            },
            {
              "lessThan": "4079f19a0e1ce76f1e21a398f02aca150ceaaf61",
              "status": "affected",
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "versionType": "git"
            },
            {
              "lessThan": "f0efaf1872949e96d213c8e910fd9517f7d7c406",
              "status": "affected",
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/gadget/function/f_midi2.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.6"
            },
            {
              "lessThan": "6.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.110",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.51",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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": "CVE-2026-90024",
  "lastModified": "2026-09-16T11:17:15.357",
  "metrics": {},
  "published": "2026-09-16T11:17:15.357",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4079f19a0e1ce76f1e21a398f02aca150ceaaf61"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/51ddc55c75087ac25342f6d73d3aeaf14f59bd76"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5b92f6a0c7c01efbb335d837ecdf34d38d98720f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9c3d5091e3568ed48ac4c5b08a78eb06fad0d70a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f0efaf1872949e96d213c8e910fd9517f7d7c406"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.


Detection rules are retrieved from Rulezet.


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.