SUSE CVE-2021-4440

In the Linux kernel, the following vulnerability has been resolved: x86/xen: Drop USERGSSYSRET64 paravirt call commit afd30525a659ac0ae0904f0cb4a2ca75522c3123 upstream. USERGSSYSRET64 is used to return from a syscall via SYSRET, but a Xen PV guest will nevertheless use the IRET hypercall, as ther...

kernel: Mishandling of indirect calls weakens Spectre mitigation for paravirtual guests

It was found that paravirtpatchcall/jump functions in the arch/x86/kernel/paravirt.c in the Linux kernel mishandles certain indirect calls, which makes it easier for attackers to conduct Spectre-v2 attacks against paravirtualized guests...