CVE-2025-39792 (GCVE-0-2025-39792)
Vulnerability from cvelistv5
Published
2025-09-12 15:59
Modified
2026-08-05 12:05
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: dm: Always split write BIOs to zoned device limits Any zoned DM target that requires zone append emulation will use the block layer zone write plugging. In such case, DM target drivers must not split BIOs using dm_accept_partial_bio() as doing so can potentially lead to deadlocks with queue freeze operations. Regular write operations used to emulate zone append operations also cannot be split by the target driver as that would result in an invalid writen sector value return using the BIO sector. In order for zoned DM target drivers to avoid such incorrect BIO splitting, we must ensure that large BIOs are split before being passed to the map() function of the target, thus guaranteeing that the limits for the mapped device are not exceeded. dm-crypt and dm-flakey are the only target drivers supporting zoned devices and using dm_accept_partial_bio(). In the case of dm-crypt, this function is used to split BIOs to the internal max_write_size limit (which will be suppressed in a different patch). However, since crypt_alloc_buffer() uses a bioset allowing only up to BIO_MAX_VECS (256) vectors in a BIO. The dm-crypt device max_segments limit, which is not set and so default to BLK_MAX_SEGMENTS (128), must thus be respected and write BIOs split accordingly. In the case of dm-flakey, since zone append emulation is not required, the block layer zone write plugging is not used and no splitting of BIOs required. Modify the function dm_zone_bio_needs_split() to use the block layer helper function bio_needs_zone_write_plugging() to force a call to bio_split_to_limits() in dm_split_and_process_bio(). This allows DM target drivers to avoid using dm_accept_partial_bio() for write operations on zoned DM devices.
References
Impacted products
Vendor Product Version
Linux Linux Version: f211268ed1f9bdf48f06a3ead5f5d88437450579
Version: f211268ed1f9bdf48f06a3ead5f5d88437450579
Version: f211268ed1f9bdf48f06a3ead5f5d88437450579
Version: f211268ed1f9bdf48f06a3ead5f5d88437450579
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/md/dm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d10bf66d9f9335ffc7521b3029b114f50604cabe",
              "status": "affected",
              "version": "f211268ed1f9bdf48f06a3ead5f5d88437450579",
              "versionType": "git"
            },
            {
              "lessThan": "f5dd256333c08ab44b5aec4a8118cb04c0f20c54",
              "status": "affected",
              "version": "f211268ed1f9bdf48f06a3ead5f5d88437450579",
              "versionType": "git"
            },
            {
              "lessThan": "4e9fef1cf0243d665d75c371cc80be6156cd30a2",
              "status": "affected",
              "version": "f211268ed1f9bdf48f06a3ead5f5d88437450579",
              "versionType": "git"
            },
            {
              "lessThan": "2df7168717b7d2d32bcf017c68be16e4aae9dd13",
              "status": "affected",
              "version": "f211268ed1f9bdf48f06a3ead5f5d88437450579",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/md/dm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.43",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.15.*",
              "status": "unaffected",
              "version": "6.15.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.43",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.15.11",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.2",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm: Always split write BIOs to zoned device limits\n\nAny zoned DM target that requires zone append emulation will use the\nblock layer zone write plugging. In such case, DM target drivers must\nnot split BIOs using dm_accept_partial_bio() as doing so can potentially\nlead to deadlocks with queue freeze operations. Regular write operations\nused to emulate zone append operations also cannot be split by the\ntarget driver as that would result in an invalid writen sector value\nreturn using the BIO sector.\n\nIn order for zoned DM target drivers to avoid such incorrect BIO\nsplitting, we must ensure that large BIOs are split before being passed\nto the map() function of the target, thus guaranteeing that the\nlimits for the mapped device are not exceeded.\n\ndm-crypt and dm-flakey are the only target drivers supporting zoned\ndevices and using dm_accept_partial_bio().\n\nIn the case of dm-crypt, this function is used to split BIOs to the\ninternal max_write_size limit (which will be suppressed in a different\npatch). However, since crypt_alloc_buffer() uses a bioset allowing only\nup to BIO_MAX_VECS (256) vectors in a BIO. The dm-crypt device\nmax_segments limit, which is not set and so default to BLK_MAX_SEGMENTS\n(128), must thus be respected and write BIOs split accordingly.\n\nIn the case of dm-flakey, since zone append emulation is not required,\nthe block layer zone write plugging is not used and no splitting of BIOs\nrequired.\n\nModify the function dm_zone_bio_needs_split() to use the block layer\nhelper function bio_needs_zone_write_plugging() to force a call to\nbio_split_to_limits() in dm_split_and_process_bio(). This allows DM\ntarget drivers to avoid using dm_accept_partial_bio() for write\noperations on zoned DM devices."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The defect is reached by submitting write I/O to a local device-mapper (dm-crypt) target stacked on a zoned block device, via ordinary write()/pwrite()/mmap or direct block-device access. No network protocol handler is involved.\nAC:L - dm-crypt\u0027s max_write_size defaults to 128 KB, so any write larger than that on a zoned dm-crypt target deterministically takes the unsplit/mis-split path \u2014 no race to win and no memory layout to groom; the attacker simply issues a large write.\nPR:L - Only an unprivileged local user with write access to a filesystem residing on the zoned dm-crypt device is needed to issue the triggering BIOs; root is required only to have configured the device beforehand, which is the deployment scenario, not an attack prerequisite.\nUI:N - The attacker\u0027s own write operations trigger the flaw; no victim must open a file, mount a filesystem, or take any other action.\nS:U - The deadlock and the data corruption are confined to the kernel and the storage stack of the same system; no VM, IOMMU, or other security-authority boundary is crossed.\nC:H - Emulated zone append returns an invalid written sector, so the filesystem records extents at locations other than where the data actually landed; subsequent reads of those extents return unrelated on-disk content (no data checksums on xfs), exposing other files\u0027/users\u0027 data on a shared volume.\nI:H - The incorrect written-sector reporting causes persistent on-disk data corruption in xfs and btrfs on zoned dm-crypt volumes, with writes and metadata landing at wrong sectors and clobbering data outside the attacker\u0027s own files.\nA:H - A split write BIO\u0027s remainder is re-plugged and calls blk_queue_enter() from the zone write plug work, deadlocking against a concurrent queue freeze while DM submission still holds the BIOs the freeze is waiting for \u2014 an unrecoverable I/O hang requiring reboot."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:05:12.947Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d10bf66d9f9335ffc7521b3029b114f50604cabe"
        },
        {
          "url": "https://git.kernel.org/stable/c/f5dd256333c08ab44b5aec4a8118cb04c0f20c54"
        },
        {
          "url": "https://git.kernel.org/stable/c/4e9fef1cf0243d665d75c371cc80be6156cd30a2"
        },
        {
          "url": "https://git.kernel.org/stable/c/2df7168717b7d2d32bcf017c68be16e4aae9dd13"
        }
      ],
      "title": "dm: Always split write BIOs to zoned device limits",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-39792",
    "datePublished": "2025-09-12T15:59:29.477Z",
    "dateReserved": "2025-04-16T07:20:57.132Z",
    "dateUpdated": "2026-08-05T12:05:12.947Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.