Vulnerability-Lookup

GHSA-CG89-59R4-QFHP

Vulnerability from github – Published: 2026-04-24 15:32 – Updated: 2026-04-27 21:30

Details

In the Linux kernel, the following vulnerability has been resolved:

mm/vma: fix memory leak in __mmap_region()

commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path.

When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which allocates a new shmem file to back the mapping. If __mmap_new_vma() subsequently fails, this replacement file is never fput()'d - the original is released by ksys_mmap_pgoff(), but nobody releases the new one.

Add fput() for the swapped file in the error path.

Reproducible with fault injection.

FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0x164/0x1f0 should_fail_ex+0x525/0x650 should_failslab+0xdf/0x140 kmem_cache_alloc_noprof+0x78/0x630 vm_area_alloc+0x24/0x160 __mmap_region+0xf6b/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e

kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) BUG: memory leak unreferenced object 0xffff8881118aca80 (size 360): comm "syz.7.14", pid 366, jiffies 4294913255 hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff .........(M..... backtrace (crc db0f53bc): kmem_cache_alloc_noprof+0x3ab/0x630 alloc_empty_file+0x5a/0x1e0 alloc_file_pseudo+0x135/0x220 __shmem_file_setup+0x274/0x420 shmem_zero_setup_desc+0x9c/0x170 mmap_zero_prepare+0x123/0x140 __mmap_region+0xdda/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Found by syzkaller.

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-31654"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-401"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-24T15:16:44Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/vma: fix memory leak in __mmap_region()\n\ncommit 605f6586ecf7 (\"mm/vma: do not leak memory when .mmap_prepare\nswaps the file\") handled the success path by skipping get_file() via\nfile_doesnt_need_get, but missed the error path.\n\nWhen /dev/zero is mmap\u0027d with MAP_SHARED, mmap_zero_prepare() calls\nshmem_zero_setup_desc() which allocates a new shmem file to back the\nmapping. If __mmap_new_vma() subsequently fails, this replacement\nfile is never fput()\u0027d - the original is released by\nksys_mmap_pgoff(), but nobody releases the new one.\n\nAdd fput() for the swapped file in the error path.\n\nReproducible with fault injection.\n\nFAULT_INJECTION: forcing a failure.\nname failslab, interval 1, probability 0, space 0, times 1\nCPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full)\nHardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n dump_stack_lvl+0x164/0x1f0\n should_fail_ex+0x525/0x650\n should_failslab+0xdf/0x140\n kmem_cache_alloc_noprof+0x78/0x630\n vm_area_alloc+0x24/0x160\n __mmap_region+0xf6b/0x2660\n mmap_region+0x2eb/0x3a0\n do_mmap+0xc79/0x1240\n vm_mmap_pgoff+0x252/0x4c0\n ksys_mmap_pgoff+0xf8/0x120\n __x64_sys_mmap+0x12a/0x190\n do_syscall_64+0xa9/0x580\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n \u003c/TASK\u003e\n\nkmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)\nBUG: memory leak\nunreferenced object 0xffff8881118aca80 (size 360):\n  comm \"syz.7.14\", pid 366, jiffies 4294913255\n  hex dump (first 32 bytes):\n    00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00  .....N..........\n    ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff  .........(M.....\n  backtrace (crc db0f53bc):\n    kmem_cache_alloc_noprof+0x3ab/0x630\n    alloc_empty_file+0x5a/0x1e0\n    alloc_file_pseudo+0x135/0x220\n    __shmem_file_setup+0x274/0x420\n    shmem_zero_setup_desc+0x9c/0x170\n    mmap_zero_prepare+0x123/0x140\n    __mmap_region+0xdda/0x2660\n    mmap_region+0x2eb/0x3a0\n    do_mmap+0xc79/0x1240\n    vm_mmap_pgoff+0x252/0x4c0\n    ksys_mmap_pgoff+0xf8/0x120\n    __x64_sys_mmap+0x12a/0x190\n    do_syscall_64+0xa9/0x580\n    entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nFound by syzkaller.",
  "id": "GHSA-cg89-59r4-qfhp",
  "modified": "2026-04-27T21:30:50Z",
  "published": "2026-04-24T15:32:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31654"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/61fc8eaf2ab214b32c7bce52597c80cf0ca41ada"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/894f99eb535edc4514f756818f3c4f688ba53a59"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-31654 (GCVE-0-2026-31654)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:45 – Updated: 2026-05-11 22:12

Title

mm/vma: fix memory leak in __mmap_region()

Summary

In the Linux kernel, the following vulnerability has been resolved: mm/vma: fix memory leak in __mmap_region() commit 605f6586ecf7 ("mm/vma: do not leak memory when .mmap_prepare swaps the file") handled the success path by skipping get_file() via file_doesnt_need_get, but missed the error path. When /dev/zero is mmap'd with MAP_SHARED, mmap_zero_prepare() calls shmem_zero_setup_desc() which allocates a new shmem file to back the mapping. If __mmap_new_vma() subsequently fails, this replacement file is never fput()'d - the original is released by ksys_mmap_pgoff(), but nobody releases the new one. Add fput() for the swapped file in the error path. Reproducible with fault injection. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x164/0x1f0 should_fail_ex+0x525/0x650 should_failslab+0xdf/0x140 kmem_cache_alloc_noprof+0x78/0x630 vm_area_alloc+0x24/0x160 __mmap_region+0xf6b/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) BUG: memory leak unreferenced object 0xffff8881118aca80 (size 360): comm "syz.7.14", pid 366, jiffies 4294913255 hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff .........(M..... backtrace (crc db0f53bc): kmem_cache_alloc_noprof+0x3ab/0x630 alloc_empty_file+0x5a/0x1e0 alloc_file_pseudo+0x135/0x220 __shmem_file_setup+0x274/0x420 shmem_zero_setup_desc+0x9c/0x170 mmap_zero_prepare+0x123/0x140 __mmap_region+0xdda/0x2660 mmap_region+0x2eb/0x3a0 do_mmap+0xc79/0x1240 vm_mmap_pgoff+0x252/0x4c0 ksys_mmap_pgoff+0xf8/0x120 __x64_sys_mmap+0x12a/0x190 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x76/0x7e Found by syzkaller.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/61fc8eaf2ab214b32…
https://git.kernel.org/stable/c/894f99eb535edc451…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 605f6586ecf78395f0185ab24c368fb46a06e434 , < 61fc8eaf2ab214b32c7bce52597c80cf0ca41ada (git) Affected: 605f6586ecf78395f0185ab24c368fb46a06e434 , < 894f99eb535edc4514f756818f3c4f688ba53a59 (git)
Linux	Linux	Affected: 6.19 Unaffected: 0 , < 6.19 (semver) Unaffected: 6.19.13 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "mm/vma.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "61fc8eaf2ab214b32c7bce52597c80cf0ca41ada",
              "status": "affected",
              "version": "605f6586ecf78395f0185ab24c368fb46a06e434",
              "versionType": "git"
            },
            {
              "lessThan": "894f99eb535edc4514f756818f3c4f688ba53a59",
              "status": "affected",
              "version": "605f6586ecf78395f0185ab24c368fb46a06e434",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "mm/vma.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.13",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/vma: fix memory leak in __mmap_region()\n\ncommit 605f6586ecf7 (\"mm/vma: do not leak memory when .mmap_prepare\nswaps the file\") handled the success path by skipping get_file() via\nfile_doesnt_need_get, but missed the error path.\n\nWhen /dev/zero is mmap\u0027d with MAP_SHARED, mmap_zero_prepare() calls\nshmem_zero_setup_desc() which allocates a new shmem file to back the\nmapping. If __mmap_new_vma() subsequently fails, this replacement\nfile is never fput()\u0027d - the original is released by\nksys_mmap_pgoff(), but nobody releases the new one.\n\nAdd fput() for the swapped file in the error path.\n\nReproducible with fault injection.\n\nFAULT_INJECTION: forcing a failure.\nname failslab, interval 1, probability 0, space 0, times 1\nCPU: 2 UID: 0 PID: 366 Comm: syz.7.14 Not tainted 7.0.0-rc6 #2 PREEMPT(full)\nHardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n dump_stack_lvl+0x164/0x1f0\n should_fail_ex+0x525/0x650\n should_failslab+0xdf/0x140\n kmem_cache_alloc_noprof+0x78/0x630\n vm_area_alloc+0x24/0x160\n __mmap_region+0xf6b/0x2660\n mmap_region+0x2eb/0x3a0\n do_mmap+0xc79/0x1240\n vm_mmap_pgoff+0x252/0x4c0\n ksys_mmap_pgoff+0xf8/0x120\n __x64_sys_mmap+0x12a/0x190\n do_syscall_64+0xa9/0x580\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n \u003c/TASK\u003e\n\nkmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak)\nBUG: memory leak\nunreferenced object 0xffff8881118aca80 (size 360):\n  comm \"syz.7.14\", pid 366, jiffies 4294913255\n  hex dump (first 32 bytes):\n    00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00  .....N..........\n    ff ff ff ff ff ff ff ff c0 28 4d ae ff ff ff ff  .........(M.....\n  backtrace (crc db0f53bc):\n    kmem_cache_alloc_noprof+0x3ab/0x630\n    alloc_empty_file+0x5a/0x1e0\n    alloc_file_pseudo+0x135/0x220\n    __shmem_file_setup+0x274/0x420\n    shmem_zero_setup_desc+0x9c/0x170\n    mmap_zero_prepare+0x123/0x140\n    __mmap_region+0xdda/0x2660\n    mmap_region+0x2eb/0x3a0\n    do_mmap+0xc79/0x1240\n    vm_mmap_pgoff+0x252/0x4c0\n    ksys_mmap_pgoff+0xf8/0x120\n    __x64_sys_mmap+0x12a/0x190\n    do_syscall_64+0xa9/0x580\n    entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nFound by syzkaller."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:12:59.768Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/61fc8eaf2ab214b32c7bce52597c80cf0ca41ada"
        },
        {
          "url": "https://git.kernel.org/stable/c/894f99eb535edc4514f756818f3c4f688ba53a59"
        }
      ],
      "title": "mm/vma: fix memory leak in __mmap_region()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31654",
    "datePublished": "2026-04-24T14:45:06.387Z",
    "dateReserved": "2026-03-09T15:48:24.129Z",
    "dateUpdated": "2026-05-11T22:12:59.768Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
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.

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