CVE-2026-90247
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix mmap_lock leak in irq_work path stack_map_get_build_id_offset() introduced a per-CPU irq_work to defer mmap_read_unlock() from NMI context, and bpf_find_vma() later reused the same mmap_unlock_work. Both callers only check whether the work is busy before taking mmap_lock, so a nested caller can reuse the slot before the first caller queues it. Two read locks may then be acquired while only one deferred unlock runs, leaking a read lock and blocking exit_mmap(). Reserve the per-CPU slot before mmap_read_trylock(). Use the same wrapper in stackmap and bpf_find_vma() so both callers release the reservation on trylock failure. Keep rejecting the slot while the irq_work remains busy. Release it after the irq_work callback unlocks the mm.
Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-17 17:17:20.803000
Last modified
2026-10-30 13:20:47.630000
View original CVE JSON
{
"id": "CVE-2026-90247",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:17:20.803",
"lastModified": "2026-10-30T13:20:47.630",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix mmap_lock leak in irq_work path\n\nstack_map_get_build_id_offset() introduced a per-CPU irq_work to defer\nmmap_read_unlock() from NMI context, and bpf_find_vma() later reused the\nsame mmap_unlock_work. Both callers only check whether the work is busy\nbefore taking mmap_lock, so a nested caller can reuse the slot before the\nfirst caller queues it. Two read locks may then be acquired while only one\ndeferred unlock runs, leaking a read lock and blocking exit_mmap().\n\nReserve the per-CPU slot before mmap_read_trylock(). Use the same wrapper\nin stackmap and bpf_find_vma() so both callers release the reservation on\ntrylock failure. Keep rejecting the slot while the irq_work remains busy.\nRelease it after the irq_work callback unlocks the mm."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/bpf/mmap_unlock_work.h",
"kernel/bpf/stackmap.c",
"kernel/bpf/task_iter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "eac9153f2b584c702cea02c1f1a57d85aa9aea42",
"lessThan": "d6d091873e12d1de36d7228c4f452e6cace3a23e",
"versionType": "git",
"status": "affected"
},
{
"version": "eac9153f2b584c702cea02c1f1a57d85aa9aea42",
"lessThan": "b6c9daf6097f9b39162b8e736a6ac7caf5ef6fc8",
"versionType": "git",
"status": "affected"
},
{
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"status": "affected"
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{
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"status": "affected"
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"status": "affected"
},
{
"version": "eac9153f2b584c702cea02c1f1a57d85aa9aea42",
"lessThan": "fa9dcacdcdf487f0ffef64bf67622f1caed509f1",
"versionType": "git",
"status": "affected"
},
{
"version": "a7f4da875c16f3b8bef0d9ec67528111045bfcd8",
"versionType": "git",
"status": "affected"
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{
"version": "f1838da73cccb238b8be4ef464fce0168dc7ba84",
"versionType": "git",
"status": "affected"
},
{
"version": "4.19.92",
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},
{
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"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/bpf/mmap_unlock_work.h",
"kernel/bpf/stackmap.c",
"kernel/bpf/task_iter.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5.5",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.5",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.160",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.114",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.52",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.6",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/051f2da26ce377f683b938a3382e0f16d02f3139",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/931f62311c058d79f29548f20943969bb441ce87",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/b6c9daf6097f9b39162b8e736a6ac7caf5ef6fc8",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d6d091873e12d1de36d7228c4f452e6cace3a23e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}