In the Linux kernel, the following vulnerability has been resolved:
comedi: fix divide-by-zero in comedi_buf_munge()
The comedi_buf_munge() function performs a modulo operation
`async->munge_chan %= async->cmd.chanlist_len` without first
checking if chanlist_len is zero. If a user program submits a command with
chanlist_len set to zero, this causes a divide-by-zero error when the device
processes data in the interrupt handler path.
Add a check for zero chanlist_len at the beginning of the
function, similar to the existing checks for !map and
CMDF_RAWDATA flag. When chanlist_len is zero, update
munge_count and return early, indicating the data was
handled without munging.
This prevents potential kernel panics from malformed user commands.
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{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2025-40106",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"dateUpdated": "2025-10-31T09:41:46.740Z",
"dateReserved": "2025-04-16T07:20:57.166Z",
"datePublished": "2025-10-31T09:41:46.740Z",
"state": "PUBLISHED"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2025-10-31T09:41:46.740Z"
},
"title": "comedi: fix divide-by-zero in comedi_buf_munge()",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncomedi: fix divide-by-zero in comedi_buf_munge()\n\nThe comedi_buf_munge() function performs a modulo operation\n`async->munge_chan %= async->cmd.chanlist_len` without first\nchecking if chanlist_len is zero. If a user program submits a command with\nchanlist_len set to zero, this causes a divide-by-zero error when the device\nprocesses data in the interrupt handler path.\n\nAdd a check for zero chanlist_len at the beginning of the\nfunction, similar to the existing checks for !map and\nCMDF_RAWDATA flag. When chanlist_len is zero, update\nmunge_count and return early, indicating the data was\nhandled without munging.\n\nThis prevents potential kernel panics from malformed user commands."
}
],
"affected": [
{
"vendor": "Linux",
"product": "Linux",
"programFiles": [
"drivers/comedi/comedi_buf.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"defaultStatus": "unaffected",
"versions": [
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "4ffea48c69cb2b96a281cb7e5e42d706996631db"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "8f3e4cd9be4b47246ea73ce5e3e0fa2f57f0d10c"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "2670932f2465793fea1ef073e40883e8390fa4d9"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "6db19822512396be1a3e1e20c16c97270285ba1a"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "d4854eff25efb06d0d84c13e7129bbdba4125f8c"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
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"lessThan": "a4bb5d1bc2f238461bcbe5303eb500466690bb2c"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "55520f65fd447e04099a2c44185453c18ea73b7e"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"status": "affected",
"versionType": "git",
"lessThan": "87b318ba81dda2ee7b603f4f6c55e78ec3e95974"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"programFiles": [
"drivers/comedi/comedi_buf.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"defaultStatus": "affected",
"versions": [
{
"version": "5.4.301",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"version": "5.10.246",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"version": "5.15.196",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"version": "6.1.158",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"version": "6.6.115",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"version": "6.12.56",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"version": "6.17.6",
"status": "unaffected",
"versionType": "semver",
"lessThanOrEqual": "6.17.*"
},
{
"version": "6.18-rc3",
"status": "unaffected",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/4ffea48c69cb2b96a281cb7e5e42d706996631db"
},
{
"url": "https://git.kernel.org/stable/c/8f3e4cd9be4b47246ea73ce5e3e0fa2f57f0d10c"
},
{
"url": "https://git.kernel.org/stable/c/2670932f2465793fea1ef073e40883e8390fa4d9"
},
{
"url": "https://git.kernel.org/stable/c/6db19822512396be1a3e1e20c16c97270285ba1a"
},
{
"url": "https://git.kernel.org/stable/c/d4854eff25efb06d0d84c13e7129bbdba4125f8c"
},
{
"url": "https://git.kernel.org/stable/c/a4bb5d1bc2f238461bcbe5303eb500466690bb2c"
},
{
"url": "https://git.kernel.org/stable/c/55520f65fd447e04099a2c44185453c18ea73b7e"
},
{
"url": "https://git.kernel.org/stable/c/87b318ba81dda2ee7b603f4f6c55e78ec3e95974"
}
]
}
}
}