Re: [PATCH v6 01/17] ima: Add IMA namespace support

Implement an IMA namespace data structure that gets created alongside a
user namespace with CLONE_NEWUSER. This lays down the foundation for
namespacing the different aspects of IMA (eg. IMA-audit, IMA-measurement,
IMA-appraisal).

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
  include/linux/ima.h                      | 37 +++++++++++++
  include/linux/user_namespace.h           |  4 ++
  init/Kconfig                             | 10 ++++
  kernel/user.c                            |  7 +++
  kernel/user_namespace.c                  |  8 +++
  security/integrity/ima/Makefile          |  3 +-
  security/integrity/ima/ima.h             |  4 ++
  security/integrity/ima/ima_init.c        |  4 ++
  security/integrity/ima/ima_init_ima_ns.c | 32 +++++++++++
  security/integrity/ima/ima_ns.c          | 69 ++++++++++++++++++++++++
  10 files changed, 177 insertions(+), 1 deletion(-)
  create mode 100644 security/integrity/ima/ima_init_ima_ns.c
  create mode 100644 security/integrity/ima/ima_ns.c

diff --git a/include/linux/ima.h b/include/linux/ima.h
index b6ab66a546ae..f282e40c316c 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h

@@ -11,6 +11,7 @@
  #include <linux/fs.h>
  #include <linux/security.h>
  #include <linux/kexec.h>
+#include <linux/user_namespace.h>
  #include <crypto/hash_info.h>
  struct linux_binprm;
  

@@ -210,6 +211,42 @@ static inline int ima_inode_removexattr(struct dentry *dentry,
  }
  #endif /* CONFIG_IMA_APPRAISE */
  
+struct ima_namespace {
+	int avoid_zero_size;
+};