SELinux: Improve read/write performance
It reduces the selinux overhead on read/write by only revalidating
permissions in selinux_file_permission if the task or inode labels have
changed or the policy has changed since the open-time check. A new LSM
hook, security_dentry_open, is added to capture the necessary state at open
time to allow this optimization.
(see http://marc.info/?l=selinux&m=118972995207740&w=2)
Signed-off-by: Yuichi Nakamura<ynakam@hitachisoft.jp>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 91b88f0..642a9fd 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -53,6 +53,8 @@
struct file *file; /* back pointer to file object */
u32 sid; /* SID of open file description */
u32 fown_sid; /* SID of file owner (for SIGIO) */
+ u32 isid; /* SID of inode at the time of file open */
+ u32 pseqno; /* Policy seqno at the time of file open */
};
struct superblock_security_struct {