ima: add ima_inode_setxattr/removexattr function and calls
Based on xattr_permission comments, the restriction to modify 'security'
xattr is left up to the underlying fs or lsm. Ensure that not just anyone
can modify or remove 'security.ima'.
Changelog v1:
- Unless IMA-APPRAISE is configured, use stub ima_inode_removexattr()/setxattr()
functions. (Moved ima_inode_removexattr()/setxattr() to ima_appraise.c)
Changelog:
- take i_mutex to fix locking (Dmitry Kasatkin)
- ima_reset_appraise_flags should only be called when modifying or
removing the 'security.ima' xattr. Requires CAP_SYS_ADMIN privilege.
(Incorporated fix from Roberto Sassu)
- Even if allowed to update security.ima, reset the appraisal flags,
forcing re-appraisal.
- Replace CAP_MAC_ADMIN with CAP_SYS_ADMIN
- static inline ima_inode_setxattr()/ima_inode_removexattr() stubs
- ima_protect_xattr should be static
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
diff --git a/include/linux/ima.h b/include/linux/ima.h
index e2bfbb1..2c7223d 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -44,10 +44,27 @@
#ifdef CONFIG_IMA_APPRAISE
extern void ima_inode_post_setattr(struct dentry *dentry);
+extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+ const void *xattr_value, size_t xattr_value_len);
+extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name);
#else
static inline void ima_inode_post_setattr(struct dentry *dentry)
{
return;
}
+
+static inline int ima_inode_setxattr(struct dentry *dentry,
+ const char *xattr_name,
+ const void *xattr_value,
+ size_t xattr_value_len)
+{
+ return 0;
+}
+
+static inline int ima_inode_removexattr(struct dentry *dentry,
+ const char *xattr_name)
+{
+ return 0;
+}
#endif /* CONFIG_IMA_APPRAISE_H */
#endif /* _LINUX_IMA_H */