CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AI Score
Confidence
High
In the Linux kernel, the following vulnerability has been resolved:
PCI/DPC: Fix use-after-free on concurrent DPC and hot-removal
Keith reports a use-after-free when a DPC event occurs concurrently to
hot-removal of the same portion of the hierarchy:
The dpc_handler() awaits readiness of the secondary bus below the
Downstream Port where the DPC event occurred. To do so, it polls the
config space of the first child device on the secondary bus. If that
child device is concurrently removed, accesses to its struct pci_dev
cause the kernel to oops.
That’s because pci_bridge_wait_for_secondary_bus() neglects to hold a
reference on the child device. Before v6.3, the function was only
called on resume from system sleep or on runtime resume. Holding a
reference wasn’t necessary back then because the pciehp IRQ thread
could never run concurrently. (On resume from system sleep, IRQs are
not enabled until after the resume_noirq phase. And runtime resume is
always awaited before a PCI device is removed.)
However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also
called on a DPC event. Commit 53b54ad074de (“PCI/DPC: Await readiness
of secondary bus after reset”), which introduced that, failed to
appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a
reference on the child device because dpc_handler() and pciehp may
indeed run concurrently. The commit was backported to v5.10+ stable
kernels, so that’s the oldest one affected.
Add the missing reference acquisition.
Abridged stack trace:
BUG: unable to handle page fault for address: 00000000091400c0
CPU: 15 PID: 2464 Comm: irq/53-pcie-dpc 6.9.0
RIP: pci_bus_read_config_dword+0x17/0x50
pci_dev_wait()
pci_bridge_wait_for_secondary_bus()
dpc_reset_link()
pcie_do_recovery()
dpc_handler()
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 22.04 | noarch | linux | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-aws | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-aws | < any | UNKNOWN |
ubuntu | 20.04 | noarch | linux-aws-5.15 | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-azure | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-azure | < any | UNKNOWN |
ubuntu | 20.04 | noarch | linux-azure-5.15 | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-azure-fde | < any | UNKNOWN |
ubuntu | 20.04 | noarch | linux-azure-fde-5.15 | < any | UNKNOWN |
git.kernel.org/linus/11a1f4bc47362700fcbde717292158873fb847ed (6.11-rc1)
git.kernel.org/stable/c/11a1f4bc47362700fcbde717292158873fb847ed
git.kernel.org/stable/c/2c111413f38ca5cf87557cab89f6d82b0e3433e7
git.kernel.org/stable/c/2cc8973bdc4d6c928ebe38b88090a2cdfe81f42f
git.kernel.org/stable/c/b16f3ea1db47a6766a9f1169244cf1fc287a7c62
git.kernel.org/stable/c/c52f9e1a9eb40f13993142c331a6cfd334d4b91d
git.kernel.org/stable/c/f63df70b439bb8331358a306541893bf415bf1da
launchpad.net/bugs/cve/CVE-2024-42302
nvd.nist.gov/vuln/detail/CVE-2024-42302
security-tracker.debian.org/tracker/CVE-2024-42302
www.cve.org/CVERecord?id=CVE-2024-42302