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charset="UTF-8" X-Stat-Signature: y5o4pdgbynn6nn1a34jf5numgzuqbrij X-Rspam-User: X-Rspamd-Queue-Id: 049A014000F X-Rspamd-Server: rspam06 X-HE-Tag: 1670943648-858168 X-HE-Meta: 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 bjGq1xZW 9rdDF9KvDjv1bIrakq4o6nyd7VAbPa88+WYab/dlbyIl+R4+ynfJ6gncUG9h0yb4jOMLi4Gx7wIXrHaaaVPbNXFqCKksGGRbgHbzRThp2fpn6dbTMgovB9N1ajQy2T6jxPUlY X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Dec 9, 2022 at 10:29 AM Paul Moore wrote: > > On Fri, Dec 9, 2022 at 11:05 AM wrote: > > > > From: Jeff Xu > > > > 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 > > Reported-by: kernel test robot > > --- > > 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