imPC@ndo IT

Tracker / CVE-2020-29569

CVE-2020-29569

High 8.8

An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.

Affected products and versions

debian debian_linux
linux linux_kernel · 4.1.44 → 4.2
linux linux_kernel · 4.11.9 → 4.12
linux linux_kernel · 4.12 → 4.14.213
linux linux_kernel · 4.15 → 4.19.164
linux linux_kernel · 4.20 → 5.4.86
linux linux_kernel · 4.4.80 → 4.4.254
linux linux_kernel · 4.9.36 → 4.9.249
linux linux_kernel · 5.5 → 5.10.4
netapp hci_compute_node_bios
netapp solidfire_\&_hci_management_node
netapp solidfire_\&_hci_storage_node
xen xen · … → 4.14.1

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References