2026-02-14 16:27CVE-2026-23205Linux
PUBLISHED5.2

smb/client: fix memory leak in smb2_open_file()

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

smb/client: fix memory leak in smb2_open_file()

Reproducer:

1. server: directories are exported read-only

2. client: mount -t cifs //${server_ip}/export /mnt

3. client: dd if=/dev/zero of=/mnt/file bs=512 count=1000 oflag=direct

4. client: umount /mnt

5. client: sleep 1

6. client: modprobe -r cifs

The error message is as follows:

=============================================================================

BUG cifs_small_rq (Not tainted): Objects remaining on __kmem_cache_shutdown()

-----------------------------------------------------------------------------

Object 0x00000000d47521be @offset=14336

...

WARNING: mm/slub.c:1251 at __kmem_cache_shutdown+0x34e/0x440, CPU#0: modprobe/1577

...

Call Trace:

<TASK>

kmem_cache_destroy+0x94/0x190

cifs_destroy_request_bufs+0x3e/0x50 [cifs]

cleanup_module+0x4e/0x540 [cifs]

__se_sys_delete_module+0x278/0x400

__x64_sys_delete_module+0x5f/0x70

x64_sys_call+0x2299/0x2ff0

do_syscall_64+0x89/0x350

entry_SYSCALL_64_after_hwframe+0x76/0x7e

...

kmem_cache_destroy cifs_small_rq: Slab cache still has objects when called from cifs_destroy_request_bufs+0x3e/0x50 [cifs]

WARNING: mm/slab_common.c:532 at kmem_cache_destroy+0x16b/0x190, CPU#0: modprobe/1577

Affected products

Linux

Linux

< 743f70406264348c0830f38409eb6c40a42fb2db - AFFECTED

< 3a6d6b332f92990958602c1e35ce0173e2dd62e9 - AFFECTED

< b64e3b5d8d759dd4333992e4ba4dadf9359952c8 - AFFECTED

< 9ee608a64e37cea5b4b13e436c559dd0fb2ad1b5 - AFFECTED

< e3a43633023e3cacaca60d4b8972d084a2b06236 - AFFECTED

bcd15f06c7e8904116cfb06526bcc189b86aff85 - AFFECTED

Linux

6.15 - AFFECTED

< 6.15 - UNAFFECTED

<= 6.1.* - UNAFFECTED

<= 6.6.* - UNAFFECTED

<= 6.12.* - UNAFFECTED

<= 6.18.* - UNAFFECTED

<= * - UNAFFECTED

References

GitHub Security Advisories

GHSA-9rcv-5g2j-597r

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix memory leak...

https://github.com/advisories/GHSA-9rcv-5g2j-597r

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

smb/client: fix memory leak in smb2_open_file()

Reproducer:

  1. server: directories are exported read-only
  2. client: mount -t cifs //${server_ip}/export /mnt
  3. client: dd if=/dev/zero of=/mnt/file bs=512 count=1000 oflag=direct
  4. client: umount /mnt
  5. client: sleep 1
  6. client: modprobe -r cifs

The error message is as follows:

============================================================================= BUG cifs_small_rq (Not tainted): Objects remaining on __kmem_cache_shutdown()

Object 0x00000000d47521be @offset=14336 ... WARNING: mm/slub.c:1251 at __kmem_cache_shutdown+0x34e/0x440, CPU#0: modprobe/1577 ... Call Trace: kmem_cache_destroy+0x94/0x190 cifs_destroy_request_bufs+0x3e/0x50 [cifs] cleanup_module+0x4e/0x540 [cifs] __se_sys_delete_module+0x278/0x400 __x64_sys_delete_module+0x5f/0x70 x64_sys_call+0x2299/0x2ff0 do_syscall_64+0x89/0x350 entry_SYSCALL_64_after_hwframe+0x76/0x7e ... kmem_cache_destroy cifs_small_rq: Slab cache still has objects when called from cifs_destroy_request_bufs+0x3e/0x50 [cifs] WARNING: mm/slab_common.c:532 at kmem_cache_destroy+0x16b/0x190, CPU#0: modprobe/1577

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-23205
Click to expand
{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-23205",
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "dateUpdated": "2026-02-14T16:27:28.409Z",
    "dateReserved": "2026-01-13T15:37:45.986Z",
    "datePublished": "2026-02-14T16:27:28.409Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux",
        "dateUpdated": "2026-02-14T16:27:28.409Z"
      },
      "title": "smb/client: fix memory leak in smb2_open_file()",
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: fix memory leak in smb2_open_file()\n\nReproducer:\n\n  1. server: directories are exported read-only\n  2. client: mount -t cifs //${server_ip}/export /mnt\n  3. client: dd if=/dev/zero of=/mnt/file bs=512 count=1000 oflag=direct\n  4. client: umount /mnt\n  5. client: sleep 1\n  6. client: modprobe -r cifs\n\nThe error message is as follows:\n\n  =============================================================================\n  BUG cifs_small_rq (Not tainted): Objects remaining on __kmem_cache_shutdown()\n  -----------------------------------------------------------------------------\n\n  Object 0x00000000d47521be @offset=14336\n  ...\n  WARNING: mm/slub.c:1251 at __kmem_cache_shutdown+0x34e/0x440, CPU#0: modprobe/1577\n  ...\n  Call Trace:\n   <TASK>\n   kmem_cache_destroy+0x94/0x190\n   cifs_destroy_request_bufs+0x3e/0x50 [cifs]\n   cleanup_module+0x4e/0x540 [cifs]\n   __se_sys_delete_module+0x278/0x400\n   __x64_sys_delete_module+0x5f/0x70\n   x64_sys_call+0x2299/0x2ff0\n   do_syscall_64+0x89/0x350\n   entry_SYSCALL_64_after_hwframe+0x76/0x7e\n  ...\n  kmem_cache_destroy cifs_small_rq: Slab cache still has objects when called from cifs_destroy_request_bufs+0x3e/0x50 [cifs]\n  WARNING: mm/slab_common.c:532 at kmem_cache_destroy+0x16b/0x190, CPU#0: modprobe/1577"
        }
      ],
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2file.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "17e53a15e64b65623b8f2b1185d27d7b1cbf69ab",
              "status": "affected",
              "versionType": "git",
              "lessThan": "743f70406264348c0830f38409eb6c40a42fb2db"
            },
            {
              "version": "18066188eb90cc0c798f3370a8078a79ddb73f70",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3a6d6b332f92990958602c1e35ce0173e2dd62e9"
            },
            {
              "version": "6ebb9d54eccc8026b386e76eff69364d33373da5",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b64e3b5d8d759dd4333992e4ba4dadf9359952c8"
            },
            {
              "version": "e255612b5ed9f179abe8196df7c2ba09dd227900",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9ee608a64e37cea5b4b13e436c559dd0fb2ad1b5"
            },
            {
              "version": "e255612b5ed9f179abe8196df7c2ba09dd227900",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e3a43633023e3cacaca60d4b8972d084a2b06236"
            },
            {
              "version": "bcd15f06c7e8904116cfb06526bcc189b86aff85",
              "status": "affected",
              "versionType": "git"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2file.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.15",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.15"
            },
            {
              "version": "6.1.163",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.124",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.70",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/743f70406264348c0830f38409eb6c40a42fb2db"
        },
        {
          "url": "https://git.kernel.org/stable/c/3a6d6b332f92990958602c1e35ce0173e2dd62e9"
        },
        {
          "url": "https://git.kernel.org/stable/c/b64e3b5d8d759dd4333992e4ba4dadf9359952c8"
        },
        {
          "url": "https://git.kernel.org/stable/c/9ee608a64e37cea5b4b13e436c559dd0fb2ad1b5"
        },
        {
          "url": "https://git.kernel.org/stable/c/e3a43633023e3cacaca60d4b8972d084a2b06236"
        }
      ]
    }
  }
}