CVE-2026-68449
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: ata: sata_dwc_460ex: fix infinite loop in NCQ tag completion bit-scanning The hand-rolled bit-scanning loop in the NCQ completion path has an infinite loop bug. When tag_mask has only high bits set (e.g. 0x80000000), the inner while loop left-shifts tag_mask until it overflows to 0. At that point !(0 & 1) is always true and 0 <<= 1 stays 0, causing an infinite loop in hardirq context with a spinlock held. Replace the open-coded bit-scanning with __ffs() which correctly finds the least significant set bit and is bounded by the width of the argument.
Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-12 01:17:07.810000
Last modified
2026-10-30 13:19:46.003000
View original CVE JSON
{
"id": "CVE-2026-68449",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-08-12T01:17:07.810",
"lastModified": "2026-10-30T13:19:46.003",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nata: sata_dwc_460ex: fix infinite loop in NCQ tag completion bit-scanning\n\nThe hand-rolled bit-scanning loop in the NCQ completion path has an\ninfinite loop bug. When tag_mask has only high bits set (e.g.\n0x80000000), the inner while loop left-shifts tag_mask until it\noverflows to 0. At that point !(0 & 1) is always true and 0 <<= 1\nstays 0, causing an infinite loop in hardirq context with a spinlock\nheld.\n\nReplace the open-coded bit-scanning with __ffs() which correctly\nfinds the least significant set bit and is bounded by the width of\nthe argument."
}
],
"affected": [
{
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"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/ata/sata_dwc_460ex.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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],
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},
{
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},
{
"version": "5.15.216",
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},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
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},
{
"version": "6.6.148",
"lessThanOrEqual": "6.6.*",
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"status": "unaffected"
},
{
"version": "6.12.101",
"lessThanOrEqual": "6.12.*",
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},
{
"version": "6.18.42",
"lessThanOrEqual": "6.18.*",
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},
{
"version": "7.1.6",
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},
{
"version": "7.2",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
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}
]
}
]
}
],
"metrics": {},
"references": [
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