On Fri, Dec 9, 2022 at 10:29 AM Paul Moore <paul@xxxxxxxxxxxxxx> wrote: > > On Fri, Dec 9, 2022 at 11:05 AM <jeffxu@xxxxxxxxxxxx> wrote: > > > > From: Jeff Xu <jeffxu@xxxxxxxxxx> > > > > The new security_memfd_create allows lsm to check flags of > > memfd_create. > > > > The security by default system (such as chromeos) can use this > > to implement system wide lsm to allow only non-executable memfd > > being created. > > > > Signed-off-by: Jeff Xu <jeffxu@xxxxxxxxxx> > > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > --- > > include/linux/lsm_hook_defs.h | 1 + > > include/linux/lsm_hooks.h | 4 ++++ > > include/linux/security.h | 6 ++++++ > > mm/memfd.c | 5 +++++ > > security/security.c | 5 +++++ > > 5 files changed, 21 insertions(+) > > We typically require at least one in-tree LSM implementation to > accompany a new LSM hook. Beyond simply providing proof that the hook > has value, it helps provide a functional example both for reviewers as > well as future LSM implementations. Also, while the BPF LSM is > definitely "in-tree", its nature is such that the actual > implementation lives out-of-tree; something like SELinux, AppArmor, > Smack, etc. are much more desirable from an in-tree example > perspective. > Thanks for the comments. Would that be OK if I add a new LSM in the kernel to block executable memfd creation ? Alternatively, it might be possible to add this into SELinux or landlock, it will be a larger change. Thanks Jeff > -- > paul-moore.com
