CVE-2025-38683 (GCVE-0-2025-38683)
Vulnerability from cvelistv5
Published
2025-09-04 15:32
Modified
2025-09-04 15:32
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: hv_netvsc: Fix panic during namespace deletion with VF The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/2a70cbd1aef8b8be39992ab7b776ce1390091774
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/33caa208dba6fa639e8a92fd0c8320b652e5550c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3467c4ebb334658c6fcf3eabb64a6e8b2135e010
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3ca41ab55d23a0aa71661a5a56a8f06c11db90dc
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4293f6c5ccf735b26afeb6825def14d830e0367b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4eff1e57a8ef98d70451b94e8437e458b27dd234
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5276896e6923ebe8c68573779d784aaf7d987cce
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d036104947176d030bec64792d54e1b4f4c7f318
Impacted products
Vendor Product Version
Linux Linux Version: 3eb6aa870057da9f1304db660f68b9c2eb7e856d
Version: b7a396f76ada277d049558db648389456458af65
Version: 4faa6e3e66b3251eb4bf5761d2f3f0f14095aaca
Version: 62c85b9a0dd7471a362170323e1211ad98ff7b4b
Version: 4c262801ea60c518b5bebc22a09f5b78b3147da2
Version: 4c262801ea60c518b5bebc22a09f5b78b3147da2
Version: 4c262801ea60c518b5bebc22a09f5b78b3147da2
Version: 4c262801ea60c518b5bebc22a09f5b78b3147da2
Version: 7abd221a55a61b6b2bf0e80f850bfc0ae75c7e01
Version: 31a38a908c98aebc7a1104dab5f1ba199f234b7b
Version: 04d748d4bd2d86739b159563f257e3dc5492c88d
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   Linux Linux Version: 6.12
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{
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhv_netvsc: Fix panic during namespace deletion with VF\n\nThe existing code move the VF NIC to new namespace when NETDEV_REGISTER is\nreceived on netvsc NIC. During deletion of the namespace,\ndefault_device_exit_batch() \u003e\u003e default_device_exit_net() is called. When\nnetvsc NIC is moved back and registered to the default namespace, it\nautomatically brings VF NIC back to the default namespace. This will cause\nthe default_device_exit_net() \u003e\u003e for_each_netdev_safe loop unable to detect\nthe list end, and hit NULL ptr:\n\n[  231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0\n[  231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010\n[  231.450246] #PF: supervisor read access in kernel mode\n[  231.450579] #PF: error_code(0x0000) - not-present page\n[  231.450916] PGD 17b8a8067 P4D 0\n[  231.451163] Oops: Oops: 0000 [#1] SMP NOPTI\n[  231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY\n[  231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024\n[  231.452692] Workqueue: netns cleanup_net\n[  231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0\n[  231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 \u003c48\u003e 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00\n[  231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246\n[  231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb\n[  231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564\n[  231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000\n[  231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340\n[  231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340\n[  231.457161] FS:  0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000\n[  231.457707] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[  231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0\n[  231.458434] Call Trace:\n[  231.458600]  \u003cTASK\u003e\n[  231.458777]  ops_undo_list+0x100/0x220\n[  231.459015]  cleanup_net+0x1b8/0x300\n[  231.459285]  process_one_work+0x184/0x340\n\nTo fix it, move the ns change to a workqueue, and take rtnl_lock to avoid\nchanging the netdev list when default_device_exit_net() is using it."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-04T15:32:38.215Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3ca41ab55d23a0aa71661a5a56a8f06c11db90dc"
        },
        {
          "url": "https://git.kernel.org/stable/c/3467c4ebb334658c6fcf3eabb64a6e8b2135e010"
        },
        {
          "url": "https://git.kernel.org/stable/c/4eff1e57a8ef98d70451b94e8437e458b27dd234"
        },
        {
          "url": "https://git.kernel.org/stable/c/2a70cbd1aef8b8be39992ab7b776ce1390091774"
        },
        {
          "url": "https://git.kernel.org/stable/c/d036104947176d030bec64792d54e1b4f4c7f318"
        },
        {
          "url": "https://git.kernel.org/stable/c/5276896e6923ebe8c68573779d784aaf7d987cce"
        },
        {
          "url": "https://git.kernel.org/stable/c/4293f6c5ccf735b26afeb6825def14d830e0367b"
        },
        {
          "url": "https://git.kernel.org/stable/c/33caa208dba6fa639e8a92fd0c8320b652e5550c"
        }
      ],
      "title": "hv_netvsc: Fix panic during namespace deletion with VF",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38683",
    "datePublished": "2025-09-04T15:32:38.215Z",
    "dateReserved": "2025-04-16T04:51:24.032Z",
    "dateUpdated": "2025-09-04T15:32:38.215Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-38683\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-09-04T16:15:36.047\",\"lastModified\":\"2025-09-05T17:47:24.833\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nhv_netvsc: Fix panic during namespace deletion with VF\\n\\nThe existing code move the VF NIC to new namespace when NETDEV_REGISTER is\\nreceived on netvsc NIC. During deletion of the namespace,\\ndefault_device_exit_batch() \u003e\u003e default_device_exit_net() is called. When\\nnetvsc NIC is moved back and registered to the default namespace, it\\nautomatically brings VF NIC back to the default namespace. This will cause\\nthe default_device_exit_net() \u003e\u003e for_each_netdev_safe loop unable to detect\\nthe list end, and hit NULL ptr:\\n\\n[  231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0\\n[  231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010\\n[  231.450246] #PF: supervisor read access in kernel mode\\n[  231.450579] #PF: error_code(0x0000) - not-present page\\n[  231.450916] PGD 17b8a8067 P4D 0\\n[  231.451163] Oops: Oops: 0000 [#1] SMP NOPTI\\n[  231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY\\n[  231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024\\n[  231.452692] Workqueue: netns cleanup_net\\n[  231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0\\n[  231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 \u003c48\u003e 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00\\n[  231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246\\n[  231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb\\n[  231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564\\n[  231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000\\n[  231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340\\n[  231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340\\n[  231.457161] FS:  0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000\\n[  231.457707] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\\n[  231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0\\n[  231.458434] Call Trace:\\n[  231.458600]  \u003cTASK\u003e\\n[  231.458777]  ops_undo_list+0x100/0x220\\n[  231.459015]  cleanup_net+0x1b8/0x300\\n[  231.459285]  process_one_work+0x184/0x340\\n\\nTo fix it, move the ns change to a workqueue, and take rtnl_lock to avoid\\nchanging the netdev list when default_device_exit_net() is using it.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/2a70cbd1aef8b8be39992ab7b776ce1390091774\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/33caa208dba6fa639e8a92fd0c8320b652e5550c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3467c4ebb334658c6fcf3eabb64a6e8b2135e010\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3ca41ab55d23a0aa71661a5a56a8f06c11db90dc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4293f6c5ccf735b26afeb6825def14d830e0367b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4eff1e57a8ef98d70451b94e8437e458b27dd234\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/5276896e6923ebe8c68573779d784aaf7d987cce\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d036104947176d030bec64792d54e1b4f4c7f318\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • 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.