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CVE-2026-90024

Full vulnerability record from the local CVENow database.

Description

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

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 11:17:15.357000
Last modified
2026-10-19 09:18:50.473000
View original CVE JSON
{
  "id": "CVE-2026-90024",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:17:15.357",
  "lastModified": "2026-10-19T09:18:50.473",
  "vulnStatus": "Received",
  "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->card 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->card to determine the\nnumber of requests to free, leading to a crash.\n\nFix this by using usb_ep->num_reqs instead of usb_ep->card->info.num_reqs\nin f_midi2_free_ep_reqs(). usb_ep->num_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 <TASK>\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"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/usb/gadget/function/f_midi2.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "lessThan": "51ddc55c75087ac25342f6d73d3aeaf14f59bd76",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "lessThan": "5b92f6a0c7c01efbb335d837ecdf34d38d98720f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "lessThan": "9c3d5091e3568ed48ac4c5b08a78eb06fad0d70a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "lessThan": "4079f19a0e1ce76f1e21a398f02aca150ceaaf61",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "8b645922b22303cec4628dbbbf6c8553d1cdec87",
              "lessThan": "f0efaf1872949e96d213c8e910fd9517f7d7c406",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/usb/gadget/function/f_midi2.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.6",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.6",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "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",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}