Re: [PATCH] x86_64: move cpu_current_top_of_stack out of TSS

On Fri, Jan 22, 2021 at 11:48 PM Lai Jiangshan wrote: > > From: Lai Jiangshan > > When X86_BUG_CPU_MELTDOWN & KPTI, cpu_current_top_of_stack lives in the > TSS which is also in the user CR3 and it becomes a coveted fruit. An > attacker can fetch the kernel stack top from it and continue next ste

[PATCH] x86_64: move cpu_current_top_of_stack out of TSS

From: Lai Jiangshan When X86_BUG_CPU_MELTDOWN & KPTI, cpu_current_top_of_stack lives in the TSS which is also in the user CR3 and it becomes a coveted fruit. An attacker can fetch the kernel stack top from it and continue next steps of actions based on the kernel stack. The address might not be