linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: PCI: pciehp: Fix infinite loop in IRQ handler upon power fault The Power Fault Detected bit in the Slot Status register differs from all other hotplug events in that it is sticky: It can only be cleared after turning off slot power. Per PCIe r5.0, sec. 6.7.1.8: If a power controller detects a main power fault on the hot-plug slot, it must automatically set its internal main power fault latch [...]. The main power fault latch is cleared when software turns off power to the hot-plug slot. The stickiness used to cause interrupt storms and infinite loops which were fixed in 2009 by commits 5651c48cfafe ("PCI pciehp: fix power fault interrupt storm problem") and 99f0169c17f3 ("PCI: pciehp: enable software notification on empty slots"). Unfortunately in 2020 the infinite loop issue was inadvertently reintroduced by commit 8edf5332c393 ("PCI: pciehp: Fix MSI interrupt race"): The hardirq handler pciehp_isr() clears the PFD bit until pciehp's power_fault_detected flag is set. That happens in the IRQ thread pciehp_ist(), which never learns of the event because the hardirq handler is stuck in an infinite loop. Fix by setting the power_fault_detected flag already in the hardirq handler.
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 5.16.7-1
- CVEs
- CVE-2021-47617
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 01:02 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: PCI: pciehp: Fix infinite loop in IRQ handler upon power fault The Power Fault Detected bit in the Slot Status register differs from all other hotplug events in that it is sticky: It can only be cleared after turning off slot power. Per PCIe r5.0, sec. 6.7.1.8: If a power controller detects a main power fault on the hot-plug slot, it must automatically set its internal main power fault latch [...]. The main power fault latch is cleared when software turns off power to the hot-plug slot. The stickiness used to cause interrupt storms and infinite loops which were fixed in 2009 by commits 5651c48cfafe ("PCI pciehp: fix power fault interrupt storm problem") and 99f0169c17f3 ("PCI: pciehp: enable software notification on empty slots"). Unfortunately in 2020 the infinite loop issue was inadvertently reintroduced by commit 8edf5332c393 ("PCI: pciehp: Fix MSI interrupt race"): The hardirq handler pciehp_isr() clears the PFD bit until pciehp's power_fault_detected flag is set. That happens in the IRQ thread pciehp_ist(), which never learns of the event because the hardirq handler is stuck in an infinite loop. Fix by setting the power_fault_detected flag already in the hardirq handler.
osv:DEBIAN-CVE-2021-47617
linux
Fixed versions: 5.16.7-1
linux
Fixed versions: 5.16.7-1
linux
Fixed versions: 5.16.7-1
Complete source record
{
"id": "b880868621a4840e71598dd96e41aaae4ee98eae896e2dcd9d2a4358710ff020",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-47617",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-47617",
"summary": "In the Linux kernel, the following vulnerability has been resolved: PCI: pciehp: Fix infinite loop in IRQ handler upon power fault The Power Fault Detected bit in the Slot Status register differs from all other hotplug events in that it is sticky: It can only be cleared after turning off slot power. Per PCIe r5.0, sec. 6.7.1.8: If a power controller detects a main power fault on the hot-plug slot, it must automatically set its internal main power fault latch [...]. The main power fault latch is cleared when software turns off power to the hot-plug slot. The stickiness used to cause interrupt storms and infinite loops which were fixed in 2009 by commits 5651c48cfafe (\"PCI pciehp: fix power fault interrupt storm problem\") and 99f0169c17f3 (\"PCI: pciehp: enable software notification on empty slots\"). Unfortunately in 2020 the infinite loop issue was inadvertently reintroduced by commit 8edf5332c393 (\"PCI: pciehp: Fix MSI interrupt race\"): The hardirq handler pciehp_isr() clears the PFD bit until pciehp's power_fault_detected flag is set. That happens in the IRQ thread pciehp_ist(), which never learns of the event because the hardirq handler is stuck in an infinite loop. Fix by setting the power_fault_detected flag already in the hardirq handler.",
"evidence": "osv:DEBIAN-CVE-2021-47617",
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"severity": "medium",
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"aliases": [
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"metrics": [
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"affected": [
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"ecosystem": "Debian:12"
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"database_specific": {
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"package": {
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{
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"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=forky",
"ecosystem": "Debian:14"
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47617.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:04:02.002009434Z",
"provider": "osv",
"upstream": [
"CVE-2021-47617"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-47617"
]
},
"related_cves": [
{
"value": "CVE-2021-47617",
"evidence": "/upstream"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 423017,
"published_at": "2024-06-20T11:15:54.317+00:00"
}