{
  "id": "CVE-2021-47617",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2024-06-20T11:15:54.317",
  "lastModified": "2024-06-20T11:15:54.317",
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: pciehp: Fix infinite loop in IRQ handler upon power fault\n\nThe Power Fault Detected bit in the Slot Status register differs from\nall other hotplug events in that it is sticky:  It can only be cleared\nafter turning off slot power.  Per PCIe r5.0, sec. 6.7.1.8:\n\n  If a power controller detects a main power fault on the hot-plug slot,\n  it must automatically set its internal main power fault latch [...].\n  The main power fault latch is cleared when software turns off power to\n  the hot-plug slot.\n\nThe stickiness used to cause interrupt storms and infinite loops which\nwere fixed in 2009 by commits 5651c48cfafe (\"PCI pciehp: fix power fault\ninterrupt storm problem\") and 99f0169c17f3 (\"PCI: pciehp: enable\nsoftware notification on empty slots\").\n\nUnfortunately in 2020 the infinite loop issue was inadvertently\nreintroduced by commit 8edf5332c393 (\"PCI: pciehp: Fix MSI interrupt\nrace\"):  The hardirq handler pciehp_isr() clears the PFD bit until\npciehp's power_fault_detected flag is set.  That happens in the IRQ\nthread pciehp_ist(), which never learns of the event because the hardirq\nhandler is stuck in an infinite loop.  Fix by setting the\npower_fault_detected flag already in the hardirq handler."
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1db58c6584a72102e98af2e600ea184ddaf2b8af",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/23584c1ed3e15a6f4bfab8dc5a88d94ab929ee12",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3b4c966fb156ff3e70b2526d964952ff7c1574d9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/464da38ba827f670deac6500a1de9a4f0f44c41d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6d6f1f0dac3e3441ecdb1103d4efb11b9ed24dd5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ff27f7d0333cff89ec85c419f431aca1b38fb16a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}