vfio/pci: Disable auto-enable of exclusive INTx IRQ
3Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackepss 0.2%
exploitation probability
0.2%top 86% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
vfio/pci: Disable auto-enable of exclusive INTx IRQ
Currently for devices requiring masking at the irqchip for INTx, ie.
devices without DisINTx support, the IRQ is enabled in request_irq()
and subsequently disabled as necessary to align with the masked status
flag. This presents a window where the interrupt could fire between
these events, resulting in the IRQ incrementing the disable depth twice.
This would be unrecoverable for a user since the masked flag prevents
nested enables through vfio.
Instead, invert the logic using IRQF_NO_AUTOEN such that exclusive INTx
is never auto-enabled, then unmask as required.
Affected products
Linux · LinuxReferences
https://cert-portal.siemens.com/productcert/html/ssa-265688.htmlhttps://git.kernel.org/stable/c/139dfcc4d723ab13469881200c7d80f49d776060https://git.kernel.org/stable/c/26389925d6c2126fb777821a0a983adca7ee6351https://git.kernel.org/stable/c/2a4a666c45107206605b7b5bc20545f8aabc4fa2https://git.kernel.org/stable/c/3b3491ad0f80d913e7d255941d4470f4a4d9bfdahttps://git.kernel.org/stable/c/561d5e1998d58b54ce2bbbb3e843b669aa0b3db5https://git.kernel.org/stable/c/b7a2f0955ffceffadfe098b40b50307431f45438https://git.kernel.org/stable/c/bf0bc84a20e6109ab07d5dc072067bd01eb931echttps://git.kernel.org/stable/c/fe9a7082684eb059b925c535682e68c34d487d43https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html