On 2022/5/18 10:56 PM, Matthew Wilcox wrote:
On Wed, May 18, 2022 at 04:51:06PM +0200, David Hildenbrand wrote:
yes, I talked about the involved challenges, especially, how malicious
user space can trigger allocation of almost elusively page tables and
essentially consume a lot of unmovable+unswappable memory and even store
secrets in the page table structure.
There are a lot of ways for userspace to consume a large amount of
kernel memory. For example, one can open a file and set file locks on
Yes, malicious programs are really hard to avoid, maybe we should try to
solve some common cases first (such as empty PTE tables).
alternate bytes. We generally handle this by accounting the memory to
the process and let the OOM killer, rlimits, memcg or other mechanism
take care of it. Just because page tables are (generally) reclaimable
doesn't mean we need to treat them specially.
--
Thanks,
Qi
