Vulnerability-Lookup

GHSA-XMX8-5V8V-4MHJ

Vulnerability from github – Published: 2024-09-18 09:30 – Updated: 2024-11-20 18:32

Details

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

mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook

When enable CONFIG_MEMCG & CONFIG_KFENCE & CONFIG_KMEMLEAK, the following warning always occurs,This is because the following call stack occurred: mem_pool_alloc kmem_cache_alloc_noprof slab_alloc_node kfence_alloc

Once the kfence allocation is successful,slab->obj_exts will not be empty, because it has already been assigned a value in kfence_init_pool.

Since in the prepare_slab_obj_exts_hook function,we perform a check for s->flags & (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function will not be called as a result.Therefore,ref->ct remains NULL.

However,when we call mem_pool_free,since obj_ext is not empty, it eventually leads to the alloc_tag_sub scenario being invoked. This is where the warning occurs.

So we should add corresponding checks in the alloc_tagging_slab_free_hook. For __GFP_NO_OBJ_EXT case,I didn't see the specific case where it's using kfence,so I won't add the corresponding check in alloc_tagging_slab_free_hook for now.

[ 3.734349] ------------[ cut here ]------------ [ 3.734807] alloc_tag was not set [ 3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574 [ 3.735866] Modules linked in: autofs4 [ 3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G W 6.11.0-rc3-dirty #1 [ 3.736969] Tainted: [W]=WARN [ 3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 [ 3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 3.738501] pc : kmem_cache_free+0x444/0x574 [ 3.738951] lr : kmem_cache_free+0x444/0x574 [ 3.739361] sp : ffff80008357bb60 [ 3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000 [ 3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700 [ 3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000 [ 3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff [ 3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0 [ 3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337 [ 3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0 [ 3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff [ 3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001 [ 3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000 [ 3.746255] Call trace: [ 3.746530] kmem_cache_free+0x444/0x574 [ 3.746931] mem_pool_free+0x44/0xf4 [ 3.747306] free_object_rcu+0xc8/0xdc [ 3.747693] rcu_do_batch+0x234/0x8a4 [ 3.748075] rcu_core+0x230/0x3e4 [ 3.748424] rcu_core_si+0x14/0x1c [ 3.748780] handle_softirqs+0x134/0x378 [ 3.749189] run_ksoftirqd+0x70/0x9c [ 3.749560] smpboot_thread_fn+0x148/0x22c [ 3.749978] kthread+0x10c/0x118 [ 3.750323] ret_from_fork+0x10/0x20 [ 3.750696] ---[ end trace 0000000000000000 ]---

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-2024-46789"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-09-18T08:15:05Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/slub: add check for s-\u003eflags in the alloc_tagging_slab_free_hook\n\nWhen enable CONFIG_MEMCG \u0026 CONFIG_KFENCE \u0026 CONFIG_KMEMLEAK, the following\nwarning always occurs,This is because the following call stack occurred:\nmem_pool_alloc\n    kmem_cache_alloc_noprof\n        slab_alloc_node\n            kfence_alloc\n\nOnce the kfence allocation is successful,slab-\u003eobj_exts will not be empty,\nbecause it has already been assigned a value in kfence_init_pool.\n\nSince in the prepare_slab_obj_exts_hook function,we perform a check for\ns-\u003eflags \u0026 (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function\nwill not be called as a result.Therefore,ref-\u003ect remains NULL.\n\nHowever,when we call mem_pool_free,since obj_ext is not empty, it\neventually leads to the alloc_tag_sub scenario being invoked.  This is\nwhere the warning occurs.\n\nSo we should add corresponding checks in the alloc_tagging_slab_free_hook.\nFor __GFP_NO_OBJ_EXT case,I didn\u0027t see the specific case where it\u0027s using\nkfence,so I won\u0027t add the corresponding check in\nalloc_tagging_slab_free_hook for now.\n\n[    3.734349] ------------[ cut here ]------------\n[    3.734807] alloc_tag was not set\n[    3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574\n[    3.735866] Modules linked in: autofs4\n[    3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G        W          6.11.0-rc3-dirty #1\n[    3.736969] Tainted: [W]=WARN\n[    3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022\n[    3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n[    3.738501] pc : kmem_cache_free+0x444/0x574\n[    3.738951] lr : kmem_cache_free+0x444/0x574\n[    3.739361] sp : ffff80008357bb60\n[    3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000\n[    3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700\n[    3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000\n[    3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff\n[    3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0\n[    3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337\n[    3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0\n[    3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff\n[    3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001\n[    3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000\n[    3.746255] Call trace:\n[    3.746530]  kmem_cache_free+0x444/0x574\n[    3.746931]  mem_pool_free+0x44/0xf4\n[    3.747306]  free_object_rcu+0xc8/0xdc\n[    3.747693]  rcu_do_batch+0x234/0x8a4\n[    3.748075]  rcu_core+0x230/0x3e4\n[    3.748424]  rcu_core_si+0x14/0x1c\n[    3.748780]  handle_softirqs+0x134/0x378\n[    3.749189]  run_ksoftirqd+0x70/0x9c\n[    3.749560]  smpboot_thread_fn+0x148/0x22c\n[    3.749978]  kthread+0x10c/0x118\n[    3.750323]  ret_from_fork+0x10/0x20\n[    3.750696] ---[ end trace 0000000000000000 ]---",
  "id": "GHSA-xmx8-5v8v-4mhj",
  "modified": "2024-11-20T18:32:15Z",
  "published": "2024-09-18T09:30:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-46789"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2d476c86ba4745fcbc912ce4627df4fa80caa9ad"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ab7ca09520e9c41c219a4427fe0dae24024bfe7f"
    }
  ],
  "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-2024-46789 (GCVE-0-2024-46789)

Vulnerability from cvelistv5 – Published: 2024-09-18 07:12 – Updated: 2026-05-11 20:36

Title

mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook

Summary

In the Linux kernel, the following vulnerability has been resolved: mm/slub: add check for s->flags in the alloc_tagging_slab_free_hook When enable CONFIG_MEMCG & CONFIG_KFENCE & CONFIG_KMEMLEAK, the following warning always occurs,This is because the following call stack occurred: mem_pool_alloc kmem_cache_alloc_noprof slab_alloc_node kfence_alloc Once the kfence allocation is successful,slab->obj_exts will not be empty, because it has already been assigned a value in kfence_init_pool. Since in the prepare_slab_obj_exts_hook function,we perform a check for s->flags & (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function will not be called as a result.Therefore,ref->ct remains NULL. However,when we call mem_pool_free,since obj_ext is not empty, it eventually leads to the alloc_tag_sub scenario being invoked. This is where the warning occurs. So we should add corresponding checks in the alloc_tagging_slab_free_hook. For __GFP_NO_OBJ_EXT case,I didn't see the specific case where it's using kfence,so I won't add the corresponding check in alloc_tagging_slab_free_hook for now. [ 3.734349] ------------[ cut here ]------------ [ 3.734807] alloc_tag was not set [ 3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574 [ 3.735866] Modules linked in: autofs4 [ 3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G W 6.11.0-rc3-dirty #1 [ 3.736969] Tainted: [W]=WARN [ 3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 [ 3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 3.738501] pc : kmem_cache_free+0x444/0x574 [ 3.738951] lr : kmem_cache_free+0x444/0x574 [ 3.739361] sp : ffff80008357bb60 [ 3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000 [ 3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700 [ 3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000 [ 3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff [ 3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0 [ 3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337 [ 3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0 [ 3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff [ 3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001 [ 3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000 [ 3.746255] Call trace: [ 3.746530] kmem_cache_free+0x444/0x574 [ 3.746931] mem_pool_free+0x44/0xf4 [ 3.747306] free_object_rcu+0xc8/0xdc [ 3.747693] rcu_do_batch+0x234/0x8a4 [ 3.748075] rcu_core+0x230/0x3e4 [ 3.748424] rcu_core_si+0x14/0x1c [ 3.748780] handle_softirqs+0x134/0x378 [ 3.749189] run_ksoftirqd+0x70/0x9c [ 3.749560] smpboot_thread_fn+0x148/0x22c [ 3.749978] kthread+0x10c/0x118 [ 3.750323] ret_from_fork+0x10/0x20 [ 3.750696] ---[ end trace 0000000000000000 ]---

Severity

No CVSS data available.

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-09-29 14:24 UTC

Assigner

Linux mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/2d476c86ba4745fcb…
https://git.kernel.org/stable/c/ab7ca09520e9c41c2…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 4b8736964640fe160724e7135dc62883bddcdace , < 2d476c86ba4745fcbc912ce4627df4fa80caa9ad (git) Affected: 4b8736964640fe160724e7135dc62883bddcdace , < ab7ca09520e9c41c219a4427fe0dae24024bfe7f (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (semver) Unaffected: 6.10.10 , ≤ 6.10.* (semver) Unaffected: 6.11 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2024-46789",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-09-29T14:24:16.008606Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-09-29T14:25:36.916Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "mm/slub.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2d476c86ba4745fcbc912ce4627df4fa80caa9ad",
              "status": "affected",
              "version": "4b8736964640fe160724e7135dc62883bddcdace",
              "versionType": "git"
            },
            {
              "lessThan": "ab7ca09520e9c41c219a4427fe0dae24024bfe7f",
              "status": "affected",
              "version": "4b8736964640fe160724e7135dc62883bddcdace",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "mm/slub.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": "6.10.*",
              "status": "unaffected",
              "version": "6.10.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.11",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.10.10",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.11",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/slub: add check for s-\u003eflags in the alloc_tagging_slab_free_hook\n\nWhen enable CONFIG_MEMCG \u0026 CONFIG_KFENCE \u0026 CONFIG_KMEMLEAK, the following\nwarning always occurs,This is because the following call stack occurred:\nmem_pool_alloc\n    kmem_cache_alloc_noprof\n        slab_alloc_node\n            kfence_alloc\n\nOnce the kfence allocation is successful,slab-\u003eobj_exts will not be empty,\nbecause it has already been assigned a value in kfence_init_pool.\n\nSince in the prepare_slab_obj_exts_hook function,we perform a check for\ns-\u003eflags \u0026 (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE),the alloc_tag_add function\nwill not be called as a result.Therefore,ref-\u003ect remains NULL.\n\nHowever,when we call mem_pool_free,since obj_ext is not empty, it\neventually leads to the alloc_tag_sub scenario being invoked.  This is\nwhere the warning occurs.\n\nSo we should add corresponding checks in the alloc_tagging_slab_free_hook.\nFor __GFP_NO_OBJ_EXT case,I didn\u0027t see the specific case where it\u0027s using\nkfence,so I won\u0027t add the corresponding check in\nalloc_tagging_slab_free_hook for now.\n\n[    3.734349] ------------[ cut here ]------------\n[    3.734807] alloc_tag was not set\n[    3.735129] WARNING: CPU: 4 PID: 40 at ./include/linux/alloc_tag.h:130 kmem_cache_free+0x444/0x574\n[    3.735866] Modules linked in: autofs4\n[    3.736211] CPU: 4 UID: 0 PID: 40 Comm: ksoftirqd/4 Tainted: G        W          6.11.0-rc3-dirty #1\n[    3.736969] Tainted: [W]=WARN\n[    3.737258] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022\n[    3.737875] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n[    3.738501] pc : kmem_cache_free+0x444/0x574\n[    3.738951] lr : kmem_cache_free+0x444/0x574\n[    3.739361] sp : ffff80008357bb60\n[    3.739693] x29: ffff80008357bb70 x28: 0000000000000000 x27: 0000000000000000\n[    3.740338] x26: ffff80008207f000 x25: ffff000b2eb2fd60 x24: ffff0000c0005700\n[    3.740982] x23: ffff8000804229e4 x22: ffff800082080000 x21: ffff800081756000\n[    3.741630] x20: fffffd7ff8253360 x19: 00000000000000a8 x18: ffffffffffffffff\n[    3.742274] x17: ffff800ab327f000 x16: ffff800083398000 x15: ffff800081756df0\n[    3.742919] x14: 0000000000000000 x13: 205d344320202020 x12: 5b5d373038343337\n[    3.743560] x11: ffff80008357b650 x10: 000000000000005d x9 : 00000000ffffffd0\n[    3.744231] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008237bad0 x6 : c0000000ffff7fff\n[    3.744907] x5 : ffff80008237ba78 x4 : ffff8000820bbad0 x3 : 0000000000000001\n[    3.745580] x2 : 68d66547c09f7800 x1 : 68d66547c09f7800 x0 : 0000000000000000\n[    3.746255] Call trace:\n[    3.746530]  kmem_cache_free+0x444/0x574\n[    3.746931]  mem_pool_free+0x44/0xf4\n[    3.747306]  free_object_rcu+0xc8/0xdc\n[    3.747693]  rcu_do_batch+0x234/0x8a4\n[    3.748075]  rcu_core+0x230/0x3e4\n[    3.748424]  rcu_core_si+0x14/0x1c\n[    3.748780]  handle_softirqs+0x134/0x378\n[    3.749189]  run_ksoftirqd+0x70/0x9c\n[    3.749560]  smpboot_thread_fn+0x148/0x22c\n[    3.749978]  kthread+0x10c/0x118\n[    3.750323]  ret_from_fork+0x10/0x20\n[    3.750696] ---[ end trace 0000000000000000 ]---"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T20:36:34.605Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2d476c86ba4745fcbc912ce4627df4fa80caa9ad"
        },
        {
          "url": "https://git.kernel.org/stable/c/ab7ca09520e9c41c219a4427fe0dae24024bfe7f"
        }
      ],
      "title": "mm/slub: add check for s-\u003eflags in the alloc_tagging_slab_free_hook",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2024-46789",
    "datePublished": "2024-09-18T07:12:45.154Z",
    "dateReserved": "2024-09-11T15:12:18.278Z",
    "dateUpdated": "2026-05-11T20:36:34.605Z",
    "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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