Hi,
[sorry for the even later reply]
I don't have a strong preference either way (between fs creds or real
creds), having the same behavior as proc_mem_open sounds like a sensible
option too. Whether moving pages between NUMA nodes is a read-only
(PTRACE_MODE_READ) activity is debatable, but I'm no NUMA expert.
My concern here was mainly about a) preventing layout discovery and b)
consistency between move_pages and migrate_pages.
Otto
On Mon, 29 Jan 2018, Michal Hocko wrote:
[Fixup Christoph email - the thread starts here
http://lkml.kernel.org/r/1394749328.5225281.1515598510696.JavaMail.zimbra@xxxxxxxxxx]
On Mon 29-01-18 14:31:51, Michal Hocko wrote:
[Sorry for a very late reply]
On Wed 10-01-18 10:21:31, Eric W. Biederman wrote:
[...]
All of that said. I am wondering if we should have used
PTRACE_MODE_READ_FSCREDS on these permission checks.
If this is really about preventing the layout discovery then we should
be in sync with proc_mem_open and that uses PTRACE_MODE_FSCREDS|PTRACE_MODE_READ
Should we do the same thing here?
--
Michal Hocko
SUSE Labs
--
Michal Hocko
SUSE Labs
