Vulnerability-Lookup

GSD-2021-46938

Vulnerability from gsd - Updated: 2024-02-26 06:03

Details

In the Linux kernel, the following vulnerability has been resolved: dm rq: fix double free of blk_mq_tag_set in dev remove after table load fails When loading a device-mapper table for a request-based mapped device, and the allocation/initialization of the blk_mq_tag_set for the device fails, a following device remove will cause a double free. E.g. (dmesg): device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device device-mapper: ioctl: unable to set up device queue for new table. Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 0305e098835de000 TEID: 0305e098835de803 Fault in home space mode while using kernel ASCE. AS:000000025efe0007 R3:0000000000000024 Oops: 0038 ilc:3 [#1] SMP Modules linked in: ... lots of modules ... Supported: Yes, External CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G W X 5.3.18-53-default #1 SLE15-SP3 Hardware name: IBM 8561 T01 7I2 (LPAR) Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000 000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000 000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640 00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8 Krnl Code: 000000025e368eb8: c4180041e100 lgrl %r1,25eba50b8 000000025e368ebe: ecba06b93a55 risbg %r11,%r10,6,185,58 #000000025e368ec4: e3b010000008 ag %r11,0(%r1) >000000025e368eca: e310b0080004 lg %r1,8(%r11) 000000025e368ed0: a7110001 tmll %r1,1 000000025e368ed4: a7740129 brc 7,25e369126 000000025e368ed8: e320b0080004 lg %r2,8(%r11) 000000025e368ede: b904001b lgr %r1,%r11 Call Trace: [<000000025e368eca>] kfree+0x42/0x330 [<000000025e5202a2>] blk_mq_free_tag_set+0x72/0xb8 [<000003ff801316a8>] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod] [<000003ff80120082>] free_dev+0x52/0xd0 [dm_mod] [<000003ff801233f0>] __dm_destroy+0x150/0x1d0 [dm_mod] [<000003ff8012bb9a>] dev_remove+0x162/0x1c0 [dm_mod] [<000003ff8012a988>] ctl_ioctl+0x198/0x478 [dm_mod] [<000003ff8012ac8a>] dm_ctl_ioctl+0x22/0x38 [dm_mod] [<000000025e3b11ee>] ksys_ioctl+0xbe/0xe0 [<000000025e3b127a>] __s390x_sys_ioctl+0x2a/0x40 [<000000025e8c15ac>] system_call+0xd8/0x2c8 Last Breaking-Event-Address: [<000000025e52029c>] blk_mq_free_tag_set+0x6c/0xb8 Kernel panic - not syncing: Fatal exception: panic_on_oops When allocation/initialization of the blk_mq_tag_set fails in dm_mq_init_request_queue(), it is uninitialized/freed, but the pointer is not reset to NULL; so when dev_remove() later gets into dm_mq_cleanup_mapped_device() it sees the pointer and tries to uninitialize and free it again. Fix this by setting the pointer to NULL in dm_mq_init_request_queue() error-handling. Also set it to NULL in dm_mq_cleanup_mapped_device().

Aliases

CVE-2021-46938

JSON

To clipboard

{
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-46938"
      ],
      "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm rq: fix double free of blk_mq_tag_set in dev remove after table load fails\n\nWhen loading a device-mapper table for a request-based mapped device,\nand the allocation/initialization of the blk_mq_tag_set for the device\nfails, a following device remove will cause a double free.\n\nE.g. (dmesg):\n  device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device\n  device-mapper: ioctl: unable to set up device queue for new table.\n  Unable to handle kernel pointer dereference in virtual kernel address space\n  Failing address: 0305e098835de000 TEID: 0305e098835de803\n  Fault in home space mode while using kernel ASCE.\n  AS:000000025efe0007 R3:0000000000000024\n  Oops: 0038 ilc:3 [#1] SMP\n  Modules linked in: ... lots of modules ...\n  Supported: Yes, External\n  CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G        W      X    5.3.18-53-default #1 SLE15-SP3\n  Hardware name: IBM 8561 T01 7I2 (LPAR)\n  Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330)\n             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3\n  Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000\n             000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000\n             000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640\n             00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8\n  Krnl Code: 000000025e368eb8: c4180041e100       lgrl    %r1,25eba50b8\n             000000025e368ebe: ecba06b93a55       risbg   %r11,%r10,6,185,58\n            #000000025e368ec4: e3b010000008       ag      %r11,0(%r1)\n            \u003e000000025e368eca: e310b0080004       lg      %r1,8(%r11)\n             000000025e368ed0: a7110001           tmll    %r1,1\n             000000025e368ed4: a7740129           brc     7,25e369126\n             000000025e368ed8: e320b0080004       lg      %r2,8(%r11)\n             000000025e368ede: b904001b           lgr     %r1,%r11\n  Call Trace:\n   [\u003c000000025e368eca\u003e] kfree+0x42/0x330\n   [\u003c000000025e5202a2\u003e] blk_mq_free_tag_set+0x72/0xb8\n   [\u003c000003ff801316a8\u003e] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod]\n   [\u003c000003ff80120082\u003e] free_dev+0x52/0xd0 [dm_mod]\n   [\u003c000003ff801233f0\u003e] __dm_destroy+0x150/0x1d0 [dm_mod]\n   [\u003c000003ff8012bb9a\u003e] dev_remove+0x162/0x1c0 [dm_mod]\n   [\u003c000003ff8012a988\u003e] ctl_ioctl+0x198/0x478 [dm_mod]\n   [\u003c000003ff8012ac8a\u003e] dm_ctl_ioctl+0x22/0x38 [dm_mod]\n   [\u003c000000025e3b11ee\u003e] ksys_ioctl+0xbe/0xe0\n   [\u003c000000025e3b127a\u003e] __s390x_sys_ioctl+0x2a/0x40\n   [\u003c000000025e8c15ac\u003e] system_call+0xd8/0x2c8\n  Last Breaking-Event-Address:\n   [\u003c000000025e52029c\u003e] blk_mq_free_tag_set+0x6c/0xb8\n  Kernel panic - not syncing: Fatal exception: panic_on_oops\n\nWhen allocation/initialization of the blk_mq_tag_set fails in\ndm_mq_init_request_queue(), it is uninitialized/freed, but the pointer\nis not reset to NULL; so when dev_remove() later gets into\ndm_mq_cleanup_mapped_device() it sees the pointer and tries to\nuninitialize and free it again.\n\nFix this by setting the pointer to NULL in dm_mq_init_request_queue()\nerror-handling. Also set it to NULL in dm_mq_cleanup_mapped_device().",
      "id": "GSD-2021-46938",
      "modified": "2024-02-26T06:03:52.768766Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "cve@kernel.org",
        "ID": "CVE-2021-46938",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "Linux",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c",
                          "version_name": "1c357a1e86a4",
                          "version_value": "8ae0185255ea"
                        },
                        {
                          "version_value": "not down converted",
                          "x_cve_json_5_version_data": {
                            "defaultStatus": "affected",
                            "versions": [
                              {
                                "status": "affected",
                                "version": "4.6"
                              },
                              {
                                "lessThan": "4.6",
                                "status": "unaffected",
                                "version": "0",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "4.9.*",
                                "status": "unaffected",
                                "version": "4.9.269",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "4.14.*",
                                "status": "unaffected",
                                "version": "4.14.233",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "4.19.*",
                                "status": "unaffected",
                                "version": "4.19.191",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "5.4.*",
                                "status": "unaffected",
                                "version": "5.4.118",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "5.10.*",
                                "status": "unaffected",
                                "version": "5.10.36",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "5.11.*",
                                "status": "unaffected",
                                "version": "5.11.20",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "5.12.*",
                                "status": "unaffected",
                                "version": "5.12.3",
                                "versionType": "custom"
                              },
                              {
                                "lessThanOrEqual": "*",
                                "status": "unaffected",
                                "version": "5.13",
                                "versionType": "original_commit_for_fix"
                              }
                            ]
                          }
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "Linux"
            }
          ]
        }
      },
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
        "description_data": [
          {
            "lang": "eng",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm rq: fix double free of blk_mq_tag_set in dev remove after table load fails\n\nWhen loading a device-mapper table for a request-based mapped device,\nand the allocation/initialization of the blk_mq_tag_set for the device\nfails, a following device remove will cause a double free.\n\nE.g. (dmesg):\n  device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device\n  device-mapper: ioctl: unable to set up device queue for new table.\n  Unable to handle kernel pointer dereference in virtual kernel address space\n  Failing address: 0305e098835de000 TEID: 0305e098835de803\n  Fault in home space mode while using kernel ASCE.\n  AS:000000025efe0007 R3:0000000000000024\n  Oops: 0038 ilc:3 [#1] SMP\n  Modules linked in: ... lots of modules ...\n  Supported: Yes, External\n  CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G        W      X    5.3.18-53-default #1 SLE15-SP3\n  Hardware name: IBM 8561 T01 7I2 (LPAR)\n  Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330)\n             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3\n  Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000\n             000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000\n             000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640\n             00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8\n  Krnl Code: 000000025e368eb8: c4180041e100       lgrl    %r1,25eba50b8\n             000000025e368ebe: ecba06b93a55       risbg   %r11,%r10,6,185,58\n            #000000025e368ec4: e3b010000008       ag      %r11,0(%r1)\n            \u003e000000025e368eca: e310b0080004       lg      %r1,8(%r11)\n             000000025e368ed0: a7110001           tmll    %r1,1\n             000000025e368ed4: a7740129           brc     7,25e369126\n             000000025e368ed8: e320b0080004       lg      %r2,8(%r11)\n             000000025e368ede: b904001b           lgr     %r1,%r11\n  Call Trace:\n   [\u003c000000025e368eca\u003e] kfree+0x42/0x330\n   [\u003c000000025e5202a2\u003e] blk_mq_free_tag_set+0x72/0xb8\n   [\u003c000003ff801316a8\u003e] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod]\n   [\u003c000003ff80120082\u003e] free_dev+0x52/0xd0 [dm_mod]\n   [\u003c000003ff801233f0\u003e] __dm_destroy+0x150/0x1d0 [dm_mod]\n   [\u003c000003ff8012bb9a\u003e] dev_remove+0x162/0x1c0 [dm_mod]\n   [\u003c000003ff8012a988\u003e] ctl_ioctl+0x198/0x478 [dm_mod]\n   [\u003c000003ff8012ac8a\u003e] dm_ctl_ioctl+0x22/0x38 [dm_mod]\n   [\u003c000000025e3b11ee\u003e] ksys_ioctl+0xbe/0xe0\n   [\u003c000000025e3b127a\u003e] __s390x_sys_ioctl+0x2a/0x40\n   [\u003c000000025e8c15ac\u003e] system_call+0xd8/0x2c8\n  Last Breaking-Event-Address:\n   [\u003c000000025e52029c\u003e] blk_mq_free_tag_set+0x6c/0xb8\n  Kernel panic - not syncing: Fatal exception: panic_on_oops\n\nWhen allocation/initialization of the blk_mq_tag_set fails in\ndm_mq_init_request_queue(), it is uninitialized/freed, but the pointer\nis not reset to NULL; so when dev_remove() later gets into\ndm_mq_cleanup_mapped_device() it sees the pointer and tries to\nuninitialize and free it again.\n\nFix this by setting the pointer to NULL in dm_mq_init_request_queue()\nerror-handling. Also set it to NULL in dm_mq_cleanup_mapped_device()."
          }
        ]
      },
      "generator": {
        "engine": "bippy-b01c2a820106"
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "n/a"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://git.kernel.org/stable/c/8ae0185255eaf05bd66f4215c81e99bf01140fd9",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/8ae0185255eaf05bd66f4215c81e99bf01140fd9"
          },
          {
            "name": "https://git.kernel.org/stable/c/b42c0a33dfdd451d9be62dd5de58c39f2750b6e3",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/b42c0a33dfdd451d9be62dd5de58c39f2750b6e3"
          },
          {
            "name": "https://git.kernel.org/stable/c/772b9f59657665af3b68d24d12b9d172d31f0dfb",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/772b9f59657665af3b68d24d12b9d172d31f0dfb"
          },
          {
            "name": "https://git.kernel.org/stable/c/a992a283c0b77d0a7c2c348add0e6a21fb1dab67",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/a992a283c0b77d0a7c2c348add0e6a21fb1dab67"
          },
          {
            "name": "https://git.kernel.org/stable/c/1cb02dc76f4c0a2749a02b26469512d6984252e9",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/1cb02dc76f4c0a2749a02b26469512d6984252e9"
          },
          {
            "name": "https://git.kernel.org/stable/c/6086f957416a6e87236c06079fcaba7a3998aeca",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/6086f957416a6e87236c06079fcaba7a3998aeca"
          },
          {
            "name": "https://git.kernel.org/stable/c/d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d"
          },
          {
            "name": "https://git.kernel.org/stable/c/8e947c8f4a5620df77e43c9c75310dc510250166",
            "refsource": "MISC",
            "url": "https://git.kernel.org/stable/c/8e947c8f4a5620df77e43c9c75310dc510250166"
          }
        ]
      }
    },
    "nvd.nist.gov": {
      "cve": {
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "487E21A9-6030-4B46-AFC1-E100B4C43057",
                    "versionEndExcluding": "4.9.269",
                    "versionStartIncluding": "4.6.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "20505383-2EB8-41EF-A91B-F185B4FB81DF",
                    "versionEndExcluding": "4.14.233",
                    "versionStartIncluding": "4.10.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "B7281E1E-A00B-49C0-A849-9CE1CE780227",
                    "versionEndExcluding": "4.19.191",
                    "versionStartIncluding": "4.15.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "5670AEA3-082C-42D6-A067-CD9ECED4B84B",
                    "versionEndExcluding": "5.4.118",
                    "versionStartIncluding": "4.20.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "C7148769-B830-4B8F-986F-E0C85A19FC7F",
                    "versionEndExcluding": "5.10.36",
                    "versionStartIncluding": "5.5.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "EFB425F0-C28C-4B44-8B4C-AD512AA832DE",
                    "versionEndExcluding": "5.11.20",
                    "versionStartIncluding": "5.11.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "C3814FA3-8141-4313-A852-8C4212BE12AD",
                    "versionEndExcluding": "5.12.3",
                    "versionStartIncluding": "5.12.0",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm rq: fix double free of blk_mq_tag_set in dev remove after table load fails\n\nWhen loading a device-mapper table for a request-based mapped device,\nand the allocation/initialization of the blk_mq_tag_set for the device\nfails, a following device remove will cause a double free.\n\nE.g. (dmesg):\n  device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device\n  device-mapper: ioctl: unable to set up device queue for new table.\n  Unable to handle kernel pointer dereference in virtual kernel address space\n  Failing address: 0305e098835de000 TEID: 0305e098835de803\n  Fault in home space mode while using kernel ASCE.\n  AS:000000025efe0007 R3:0000000000000024\n  Oops: 0038 ilc:3 [#1] SMP\n  Modules linked in: ... lots of modules ...\n  Supported: Yes, External\n  CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G        W      X    5.3.18-53-default #1 SLE15-SP3\n  Hardware name: IBM 8561 T01 7I2 (LPAR)\n  Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330)\n             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3\n  Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000\n             000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000\n             000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640\n             00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8\n  Krnl Code: 000000025e368eb8: c4180041e100       lgrl    %r1,25eba50b8\n             000000025e368ebe: ecba06b93a55       risbg   %r11,%r10,6,185,58\n            #000000025e368ec4: e3b010000008       ag      %r11,0(%r1)\n            \u003e000000025e368eca: e310b0080004       lg      %r1,8(%r11)\n             000000025e368ed0: a7110001           tmll    %r1,1\n             000000025e368ed4: a7740129           brc     7,25e369126\n             000000025e368ed8: e320b0080004       lg      %r2,8(%r11)\n             000000025e368ede: b904001b           lgr     %r1,%r11\n  Call Trace:\n   [\u003c000000025e368eca\u003e] kfree+0x42/0x330\n   [\u003c000000025e5202a2\u003e] blk_mq_free_tag_set+0x72/0xb8\n   [\u003c000003ff801316a8\u003e] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod]\n   [\u003c000003ff80120082\u003e] free_dev+0x52/0xd0 [dm_mod]\n   [\u003c000003ff801233f0\u003e] __dm_destroy+0x150/0x1d0 [dm_mod]\n   [\u003c000003ff8012bb9a\u003e] dev_remove+0x162/0x1c0 [dm_mod]\n   [\u003c000003ff8012a988\u003e] ctl_ioctl+0x198/0x478 [dm_mod]\n   [\u003c000003ff8012ac8a\u003e] dm_ctl_ioctl+0x22/0x38 [dm_mod]\n   [\u003c000000025e3b11ee\u003e] ksys_ioctl+0xbe/0xe0\n   [\u003c000000025e3b127a\u003e] __s390x_sys_ioctl+0x2a/0x40\n   [\u003c000000025e8c15ac\u003e] system_call+0xd8/0x2c8\n  Last Breaking-Event-Address:\n   [\u003c000000025e52029c\u003e] blk_mq_free_tag_set+0x6c/0xb8\n  Kernel panic - not syncing: Fatal exception: panic_on_oops\n\nWhen allocation/initialization of the blk_mq_tag_set fails in\ndm_mq_init_request_queue(), it is uninitialized/freed, but the pointer\nis not reset to NULL; so when dev_remove() later gets into\ndm_mq_cleanup_mapped_device() it sees the pointer and tries to\nuninitialize and free it again.\n\nFix this by setting the pointer to NULL in dm_mq_init_request_queue()\nerror-handling. Also set it to NULL in dm_mq_cleanup_mapped_device()."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: dm rq: corrige la liberaci\u00f3n doble de blk_mq_tag_set en dev y se elimina despu\u00e9s de que falla la carga de la tabla Al cargar una tabla de mapeador de dispositivos para un dispositivo mapeado basado en solicitudes y la asignaci\u00f3n/inicializaci\u00f3n de blk_mq_tag_set Si el dispositivo falla, la siguiente eliminaci\u00f3n del dispositivo provocar\u00e1 una doble liberaci\u00f3n. Por ejemplo, (dmesg): mapeador de dispositivos: n\u00facleo: no se puede inicializar la cola para el dispositivo asignado dm-mq basado en solicitudes mapeador de dispositivos: ioctl: no se puede configurar la cola de dispositivos para una nueva tabla. No se puede manejar la desreferencia del puntero del kernel en el espacio de direcciones virtual del kernel Direcci\u00f3n fallida: 0305e098835de000 TEID: 0305e098835de803 Fallo en el modo de espacio de inicio mientras se usa el kernel ASCE. AS:000000025efe0007 R3:0000000000000024 Ups: 0038 ilc:3 [#1] M\u00f3dulos SMP vinculados en: ... muchos m\u00f3dulos ... Compatible: S\u00ed, CPU externa: 0 PID: 7348 Comm: multipathd Kdump: cargado Contaminado: GWX 5.3.18-53-default #1 SLE15-SP3 Nombre de hardware: IBM 8561 T01 7I2 (LPAR) Krnl PSW: 0704e00180000000 000000025e368eca (kfree+0x42/0x330) R:0 T:1 IO:1 EX:1 Clave:0 M :1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 00000000000000000 000000025e520270 000000025 e8d1b40 0000000000000003 00000007aae10000 000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640 00000007a8170000 0 00003ff80138650 000000025e5202a2 000003e00396faa8 C\u00f3digo Krnl: 000000025e368eb8: c4180041e100 lgrl % r1,25eba50b8 000000025e368ebe: ecba06b93a55 risbg %r11,%r10,6,185,58 #000000025e368ec4: e3b010000008 ag %r11,0(%r1) \u0026gt;000000025e368eca: e310 b0080004 lg %r1,8(%r11) 000000025e368ed0: a7110001 tmll %r1,1 000000025e368ed4: a7740129 brc 7,25e369126 000000025e368ed8: e320b0080004 lg %r2,8(%r11) 000000025e368ede: b904001b lgr %r1,%r11 Seguimiento de llamadas: [\u0026lt;0 00000025e368eca\u0026gt;] kfree+0x42/0x330 [\u0026lt;000000025e5202a2\u0026gt;] blk_mq_free_tag_set+0x72/ 0xb8 [\u0026lt;000003ff801316a8\u0026gt;] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod] [\u0026lt;000003ff80120082\u0026gt;] free_dev+0x52/0xd0 [dm_mod] [\u0026lt;000003ff801233f0\u0026gt;] __dm_destroy+0x1 50/0x1d0 [dm_mod] [\u0026lt;000003ff8012bb9a\u0026gt;] dev_remove+0x162/0x1c0 [dm_mod] [\u0026lt;000003ff8012a988\u0026gt;] ctl_ioctl+0x198/0x478 [dm_mod] [\u0026lt;000003ff8012ac8a\u0026gt;] dm_ctl_ioctl+0x22/0x38 [dm_mod] [\u0026lt;000000025e3b11ee\u0026gt;] ksys_ioctl+0xbe /0xe0 [\u0026lt;000000025e3b127a\u0026gt;] __s390x_sys_ioctl+0x2a/0x40 [ \u0026lt;000000025e8c15ac\u0026gt;] system_call+0xd8/0x2c8 \u00daltima direcci\u00f3n del evento de \u00faltima hora: [\u0026lt;000000025e52029c\u0026gt;] blk_mq_free_tag_set+0x6c/0xb8 P\u00e1nico del kernel: no se sincroniza: excepci\u00f3n grave: p\u00e1nico_on_oops Cuando la asignaci\u00f3n/inicializaci\u00f3n de blk_mq_tag_set falla en d m_mq_init_request_queue(), no est\u00e1 inicializado/liberado, pero el puntero no se restablece a NULL; entonces, cuando dev_remove() ingresa m\u00e1s tarde a dm_mq_cleanup_mapped_device(), ve el puntero e intenta desinicializarlo y liberarlo nuevamente. Solucione este problema estableciendo el puntero en NULL en el manejo de errores dm_mq_init_request_queue(). Tambi\u00e9n config\u00farelo en NULL en dm_mq_cleanup_mapped_device()."
          }
        ],
        "id": "CVE-2021-46938",
        "lastModified": "2024-04-10T19:20:55.173",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2024-02-27T19:04:05.823",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/1cb02dc76f4c0a2749a02b26469512d6984252e9"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/6086f957416a6e87236c06079fcaba7a3998aeca"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/772b9f59657665af3b68d24d12b9d172d31f0dfb"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/8ae0185255eaf05bd66f4215c81e99bf01140fd9"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/8e947c8f4a5620df77e43c9c75310dc510250166"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/a992a283c0b77d0a7c2c348add0e6a21fb1dab67"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/b42c0a33dfdd451d9be62dd5de58c39f2750b6e3"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-415"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    }
  }
}

CVE-2021-46938 (GCVE-0-2021-46938)

Vulnerability from cvelistv5 – Published: 2024-02-27 18:40 – Updated: 2026-05-11 13:44

Title

dm rq: fix double free of blk_mq_tag_set in dev remove after table load fails

Summary

Severity

No CVSS data available.

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-02-28 20:28 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6843 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/8ae0185255eaf05bd…
https://git.kernel.org/stable/c/b42c0a33dfdd451d9…
https://git.kernel.org/stable/c/772b9f59657665af3…
https://git.kernel.org/stable/c/a992a283c0b77d0a7…
https://git.kernel.org/stable/c/1cb02dc76f4c0a274…
https://git.kernel.org/stable/c/6086f957416a6e872…
https://git.kernel.org/stable/c/d757bf4c69cda3c3a…
https://git.kernel.org/stable/c/8e947c8f4a5620df7…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < 8ae0185255eaf05bd66f4215c81e99bf01140fd9 (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < b42c0a33dfdd451d9be62dd5de58c39f2750b6e3 (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < 772b9f59657665af3b68d24d12b9d172d31f0dfb (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < a992a283c0b77d0a7c2c348add0e6a21fb1dab67 (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < 1cb02dc76f4c0a2749a02b26469512d6984252e9 (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < 6086f957416a6e87236c06079fcaba7a3998aeca (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d (git) Affected: 1c357a1e86a4227a6b6059f2de118ae47659cebc , < 8e947c8f4a5620df77e43c9c75310dc510250166 (git)
Linux	Linux	Affected: 4.6 Unaffected: 0 , < 4.6 (semver) Unaffected: 4.9.269 , ≤ 4.9.* (semver) Unaffected: 4.14.233 , ≤ 4.14.* (semver) Unaffected: 4.19.191 , ≤ 4.19.* (semver) Unaffected: 5.4.118 , ≤ 5.4.* (semver) Unaffected: 5.10.36 , ≤ 5.10.* (semver) Unaffected: 5.11.20 , ≤ 5.11.* (semver) Unaffected: 5.12.3 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-46938",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-02-28T20:28:43.150810Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-07-05T17:22:05.088Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:17:43.027Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/8ae0185255eaf05bd66f4215c81e99bf01140fd9"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/b42c0a33dfdd451d9be62dd5de58c39f2750b6e3"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/772b9f59657665af3b68d24d12b9d172d31f0dfb"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/a992a283c0b77d0a7c2c348add0e6a21fb1dab67"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/1cb02dc76f4c0a2749a02b26469512d6984252e9"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/6086f957416a6e87236c06079fcaba7a3998aeca"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/8e947c8f4a5620df77e43c9c75310dc510250166"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/md/dm-rq.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8ae0185255eaf05bd66f4215c81e99bf01140fd9",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "b42c0a33dfdd451d9be62dd5de58c39f2750b6e3",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "772b9f59657665af3b68d24d12b9d172d31f0dfb",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "a992a283c0b77d0a7c2c348add0e6a21fb1dab67",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "1cb02dc76f4c0a2749a02b26469512d6984252e9",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "6086f957416a6e87236c06079fcaba7a3998aeca",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            },
            {
              "lessThan": "8e947c8f4a5620df77e43c9c75310dc510250166",
              "status": "affected",
              "version": "1c357a1e86a4227a6b6059f2de118ae47659cebc",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/md/dm-rq.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.6"
            },
            {
              "lessThan": "4.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.9.*",
              "status": "unaffected",
              "version": "4.9.269",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.14.*",
              "status": "unaffected",
              "version": "4.14.233",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "4.19.*",
              "status": "unaffected",
              "version": "4.19.191",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.118",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.36",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.11.*",
              "status": "unaffected",
              "version": "5.11.20",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.12.*",
              "status": "unaffected",
              "version": "5.12.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.9.269",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.14.233",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.19.191",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.118",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.36",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.11.20",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.12.3",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.13",
                  "versionStartIncluding": "4.6",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm rq: fix double free of blk_mq_tag_set in dev remove after table load fails\n\nWhen loading a device-mapper table for a request-based mapped device,\nand the allocation/initialization of the blk_mq_tag_set for the device\nfails, a following device remove will cause a double free.\n\nE.g. (dmesg):\n  device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device\n  device-mapper: ioctl: unable to set up device queue for new table.\n  Unable to handle kernel pointer dereference in virtual kernel address space\n  Failing address: 0305e098835de000 TEID: 0305e098835de803\n  Fault in home space mode while using kernel ASCE.\n  AS:000000025efe0007 R3:0000000000000024\n  Oops: 0038 ilc:3 [#1] SMP\n  Modules linked in: ... lots of modules ...\n  Supported: Yes, External\n  CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G        W      X    5.3.18-53-default #1 SLE15-SP3\n  Hardware name: IBM 8561 T01 7I2 (LPAR)\n  Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330)\n             R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3\n  Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000\n             000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000\n             000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640\n             00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8\n  Krnl Code: 000000025e368eb8: c4180041e100       lgrl    %r1,25eba50b8\n             000000025e368ebe: ecba06b93a55       risbg   %r11,%r10,6,185,58\n            #000000025e368ec4: e3b010000008       ag      %r11,0(%r1)\n            \u003e000000025e368eca: e310b0080004       lg      %r1,8(%r11)\n             000000025e368ed0: a7110001           tmll    %r1,1\n             000000025e368ed4: a7740129           brc     7,25e369126\n             000000025e368ed8: e320b0080004       lg      %r2,8(%r11)\n             000000025e368ede: b904001b           lgr     %r1,%r11\n  Call Trace:\n   [\u003c000000025e368eca\u003e] kfree+0x42/0x330\n   [\u003c000000025e5202a2\u003e] blk_mq_free_tag_set+0x72/0xb8\n   [\u003c000003ff801316a8\u003e] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod]\n   [\u003c000003ff80120082\u003e] free_dev+0x52/0xd0 [dm_mod]\n   [\u003c000003ff801233f0\u003e] __dm_destroy+0x150/0x1d0 [dm_mod]\n   [\u003c000003ff8012bb9a\u003e] dev_remove+0x162/0x1c0 [dm_mod]\n   [\u003c000003ff8012a988\u003e] ctl_ioctl+0x198/0x478 [dm_mod]\n   [\u003c000003ff8012ac8a\u003e] dm_ctl_ioctl+0x22/0x38 [dm_mod]\n   [\u003c000000025e3b11ee\u003e] ksys_ioctl+0xbe/0xe0\n   [\u003c000000025e3b127a\u003e] __s390x_sys_ioctl+0x2a/0x40\n   [\u003c000000025e8c15ac\u003e] system_call+0xd8/0x2c8\n  Last Breaking-Event-Address:\n   [\u003c000000025e52029c\u003e] blk_mq_free_tag_set+0x6c/0xb8\n  Kernel panic - not syncing: Fatal exception: panic_on_oops\n\nWhen allocation/initialization of the blk_mq_tag_set fails in\ndm_mq_init_request_queue(), it is uninitialized/freed, but the pointer\nis not reset to NULL; so when dev_remove() later gets into\ndm_mq_cleanup_mapped_device() it sees the pointer and tries to\nuninitialize and free it again.\n\nFix this by setting the pointer to NULL in dm_mq_init_request_queue()\nerror-handling. Also set it to NULL in dm_mq_cleanup_mapped_device()."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T13:44:48.604Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/8ae0185255eaf05bd66f4215c81e99bf01140fd9"
        },
        {
          "url": "https://git.kernel.org/stable/c/b42c0a33dfdd451d9be62dd5de58c39f2750b6e3"
        },
        {
          "url": "https://git.kernel.org/stable/c/772b9f59657665af3b68d24d12b9d172d31f0dfb"
        },
        {
          "url": "https://git.kernel.org/stable/c/a992a283c0b77d0a7c2c348add0e6a21fb1dab67"
        },
        {
          "url": "https://git.kernel.org/stable/c/1cb02dc76f4c0a2749a02b26469512d6984252e9"
        },
        {
          "url": "https://git.kernel.org/stable/c/6086f957416a6e87236c06079fcaba7a3998aeca"
        },
        {
          "url": "https://git.kernel.org/stable/c/d757bf4c69cda3c3ab7f775dfabbf5a80e2f6f9d"
        },
        {
          "url": "https://git.kernel.org/stable/c/8e947c8f4a5620df77e43c9c75310dc510250166"
        }
      ],
      "title": "dm rq: fix double free of blk_mq_tag_set in dev remove after table load fails",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-46938",
    "datePublished": "2024-02-27T18:40:26.850Z",
    "dateReserved": "2024-02-25T13:45:52.721Z",
    "dateUpdated": "2026-05-11T13:44:48.604Z",
    "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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

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.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted