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CVE-2026-89953

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: mtd: mtdoops: free page bitmap when the backing MTD is removed mtdoops_notify_add() allocates oops_page_used when the configured MTD device is registered. mtdoops_notify_remove() detaches from that device but leaves the bitmap allocated. If the same MTD device is later registered again, the add path allocates a new bitmap and overwrites the old pointer, leaking one vmalloc allocation per remove/add cycle. This is only visible when the backing MTD device can disappear and be registered again while mtdoops remains loaded, so the usual static MTD case does not expose it. Free the bitmap after unregistering the dumper and flushing the pending workers, then clear the pointer and page count before a later attach can allocate fresh state. Clearing the pointer also keeps the module exit path from freeing the same bitmap a second time after a remove event.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 11:17:05.530000
Last modified
2026-10-19 09:18:41.337000
View original CVE JSON
{
  "id": "CVE-2026-89953",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:17:05.530",
  "lastModified": "2026-10-19T09:18:41.337",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmtd: mtdoops: free page bitmap when the backing MTD is removed\n\nmtdoops_notify_add() allocates oops_page_used when the configured MTD\ndevice is registered.  mtdoops_notify_remove() detaches from that device\nbut leaves the bitmap allocated.  If the same MTD device is later\nregistered again, the add path allocates a new bitmap and overwrites the\nold pointer, leaking one vmalloc allocation per remove/add cycle.\n\nThis is only visible when the backing MTD device can disappear and be\nregistered again while mtdoops remains loaded, so the usual static MTD\ncase does not expose it.\n\nFree the bitmap after unregistering the dumper and flushing the pending\nworkers, then clear the pointer and page count before a later attach can\nallocate fresh state.  Clearing the pointer also keeps the module exit\npath from freeing the same bitmap a second time after a remove event."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/mtd/mtdoops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "477d61d54e097e90f748aa18d013805abd56bcbd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "a91ac71e67c3e01ed9afd9841435bebb930293f8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "698944132083d143ef965c0090ee14ba1d9e1a5f",
              "versionType": "git",
              "status": "affected"
            },
            {
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              "lessThan": "f25c804947e0a28c15e73da8e2e0db959cbed716",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "8414f0e9f707226de20b48c7048179fd86d352fc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "d06f91a52af11630c9f7e487f6daf242ac310cb8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be95745f01677245a061a8f51473ef5ec8ad008e",
              "lessThan": "1e5cd8bc902331ff801df88cbb299029ae062753",
              "versionType": "git",
              "status": "affected"
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            {
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              "lessThan": "956e7da12c114f13c63d126ab1d79c3b6a819060",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/mtd/mtdoops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.33",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.33",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "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/1e5cd8bc902331ff801df88cbb299029ae062753",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/477d61d54e097e90f748aa18d013805abd56bcbd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/698944132083d143ef965c0090ee14ba1d9e1a5f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8414f0e9f707226de20b48c7048179fd86d352fc",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/956e7da12c114f13c63d126ab1d79c3b6a819060",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a91ac71e67c3e01ed9afd9841435bebb930293f8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d06f91a52af11630c9f7e487f6daf242ac310cb8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f25c804947e0a28c15e73da8e2e0db959cbed716",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}