Action not permitted
Modal body text goes here.
Modal Title
Modal Body
EUVD-2026-309448
European Vulnerability Database identifier assigned by ENISAReserved
2026-10-02 07:09
Assigner
ENISA
Alias of
a CVE record, shown under related vulnerabilities.
This identifier carries no description, severity or references of its own:
they belong to that CVE.
{
"assigner": "ENISA",
"date_reserved": "2026-10-02T07:09:07.593107+00:00",
"id": "EUVD-2026-309448"
}
CVE-2021-46938 (GCVE-0-2021-46938)
Vulnerability from cvelistv5 – Published: 2024-02-27 18:40 – Updated: 2026-05-11 13:44
VLAI
EPSS
VEX
Title
dm rq: fix double free of blk_mq_tag_set in dev remove after table load fails
Summary
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().
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
References
8 references
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) |
{
"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"
}
Loading…
Trend slope:
-
(linear fit over daily sighting counts)
Show additional events:
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
Loading…
Loading…
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.
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.
Loading…
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.
Loading…
Loading…