CVE-2026-74643 (GCVE-0-2026-74643)
Vulnerability from cvelistv5
Published
2026-08-22 15:32
Modified
2026-08-22 15:32
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
samples/damon/mtier: error out for zero quota goal target values
Patch series "mm/damon: avoid division by zero from damos_quota_score()".
DAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division
by zero in damos_quota_score(). Avoid it by adding parameters validation
checks.
This patch (of 2):
damos_quota_score() can trigger division by zero if the target_value is
zero. DAMON_SAMPLE_MTIER lets users set the target_value via
node0_mem_{used,free}_bp parameters. It doesn't guard zero value case,
though. As a result, users can trigger division by zero. Fix the issue
by returning an error when the user tries to start DAMON with zero
node0_mem_{used,free}_bp parameter values.
DAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite
bad. Also the zero node0_mem_free_bp parameter might look like a
reasonable setup to some users. Hence, the issue might really happen in
the real world.
One reliable way to reproduce the issue is like below:
# cd /sys/module/damon_sample_mtier/parameters
# echo 4096 > node0_start_addr
# echo 8192 > node0_end_addr
# echo 8192 > node1_start_addr
# echo 81920 > node1_end_addr
# echo 0 > node0_mem_free_bp
# echo Y > enabled
# dmesg -w
[...]
[18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI
[...]
[18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480
[...]
This issue was discovered [1] by Sashiko.
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"samples/damon/mtier.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "e16b8d640ec99b28bc827560edcf9706e610c3aa",
"status": "affected",
"version": "c5e67d40a10234541e220750297304df79aaedd0",
"versionType": "git"
},
{
"lessThan": "684f271210becd7b8c4088f06c442499e48a43a0",
"status": "affected",
"version": "c5e67d40a10234541e220750297304df79aaedd0",
"versionType": "git"
},
{
"lessThan": "a16fd3ad9d89b05475864da97327870464611736",
"status": "affected",
"version": "c5e67d40a10234541e220750297304df79aaedd0",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"samples/damon/mtier.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.17"
},
{
"lessThan": "6.17",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.45",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.9",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.45",
"versionStartIncluding": "6.17",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.9",
"versionStartIncluding": "6.17",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "6.17",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsamples/damon/mtier: error out for zero quota goal target values\n\nPatch series \"mm/damon: avoid division by zero from damos_quota_score()\".\n\nDAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division\nby zero in damos_quota_score(). Avoid it by adding parameters validation\nchecks.\n\n\nThis patch (of 2):\n\ndamos_quota_score() can trigger division by zero if the target_value is\nzero. DAMON_SAMPLE_MTIER lets users set the target_value via\nnode0_mem_{used,free}_bp parameters. It doesn\u0027t guard zero value case,\nthough. As a result, users can trigger division by zero. Fix the issue\nby returning an error when the user tries to start DAMON with zero\nnode0_mem_{used,free}_bp parameter values.\n\nDAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite\nbad. Also the zero node0_mem_free_bp parameter might look like a\nreasonable setup to some users. Hence, the issue might really happen in\nthe real world.\n\nOne reliable way to reproduce the issue is like below:\n\n # cd /sys/module/damon_sample_mtier/parameters\n # echo 4096 \u003e node0_start_addr\n # echo 8192 \u003e node0_end_addr\n # echo 8192 \u003e node1_start_addr\n # echo 81920 \u003e node1_end_addr\n # echo 0 \u003e node0_mem_free_bp\n # echo Y \u003e enabled\n # dmesg -w\n [...]\n [18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI\n [...]\n [18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480\n [...]\n\nThis issue was discovered [1] by Sashiko."
}
],
"providerMetadata": {
"dateUpdated": "2026-08-22T15:32:21.140Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/e16b8d640ec99b28bc827560edcf9706e610c3aa"
},
{
"url": "https://git.kernel.org/stable/c/684f271210becd7b8c4088f06c442499e48a43a0"
},
{
"url": "https://git.kernel.org/stable/c/a16fd3ad9d89b05475864da97327870464611736"
}
],
"title": "samples/damon/mtier: error out for zero quota goal target values",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-74643",
"datePublished": "2026-08-22T15:32:21.140Z",
"dateReserved": "2026-08-15T05:44:03.922Z",
"dateUpdated": "2026-08-22T15:32:21.140Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- 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.
Loading…
Loading…