apparmor/kernel-patches/2.6.27/add-security_path_permission

109 lines
3.6 KiB
Text

From: Jeff Mahoney <jeffm@suse.com>
Subject: [PATCH] security: add ->path_permission
This patch adds a security_ops->path_permission hook that is identical to
security_ops->inode_permission except that it is passed a struct path
instead of a struct inode.
LSMs which don't implement it will have their ->inode_permission call
used instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
include/linux/security.h | 21 +++++++++++++++++++++
security/capability.c | 6 ++++++
security/security.c | 9 +++++++++
3 files changed, 36 insertions(+)
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -592,6 +592,20 @@ static inline void security_free_mnt_opt
* file_permission, and recheck access if anything has changed
* since inode_permission.
*
+ * Security hook for path
+ *
+ * @path_permission:
+ * Check permission before accessing a path. This hook is called by the
+ * existing Linux permission function, so a security module can use it to
+ * provide additional checking for existing Linux permission checks.
+ * Notice that this hook is called when a file is opened (as well as many
+ * other operations), whereas the file_security_ops permission hook is
+ * called when the actual read/write operations are performed. This
+ * hook is optional and if absent, inode_permission will be substituted.
+ * @path contains the path structure to check.
+ * @mask contains the permission mask.
+ * Return 0 if permission is granted.
+
* Security hooks for task operations.
*
* @task_create:
@@ -1434,6 +1448,7 @@ struct security_operations {
struct fown_struct *fown, int sig);
int (*file_receive) (struct file *file);
int (*dentry_open) (struct file *file);
+ int (*path_permission) (struct path *path, int mask);
int (*task_create) (unsigned long clone_flags);
int (*task_alloc_security) (struct task_struct *p);
@@ -1708,6 +1723,7 @@ int security_file_send_sigiotask(struct
struct fown_struct *fown, int sig);
int security_file_receive(struct file *file);
int security_dentry_open(struct file *file);
+int security_path_permission(struct path *path, int mask);
int security_task_create(unsigned long clone_flags);
int security_task_alloc(struct task_struct *p);
void security_task_free(struct task_struct *p);
@@ -2240,6 +2256,11 @@ static inline int security_dentry_open(s
{
return 0;
}
+
+static inline int security_path_permission(struct path *path, int mask)
+{
+ return 0;
+}
static inline int security_task_create(unsigned long clone_flags)
{
--- a/security/capability.c
+++ b/security/capability.c
@@ -343,6 +343,11 @@ static int cap_dentry_open(struct file *
return 0;
}
+static int cap_path_permission(struct path *path, int mask)
+{
+ return security_inode_permission(path->dentry->d_inode, mask);
+}
+
static int cap_task_create(unsigned long clone_flags)
{
return 0;
@@ -897,6 +902,7 @@ void security_fixup_ops(struct security_
set_to_cap_if_null(ops, file_send_sigiotask);
set_to_cap_if_null(ops, file_receive);
set_to_cap_if_null(ops, dentry_open);
+ set_to_cap_if_null(ops, path_permission);
set_to_cap_if_null(ops, task_create);
set_to_cap_if_null(ops, task_alloc_security);
set_to_cap_if_null(ops, task_free_security);
--- a/security/security.c
+++ b/security/security.c
@@ -615,6 +615,15 @@ int security_dentry_open(struct file *fi
return security_ops->dentry_open(file);
}
+int security_path_permission(struct path *path, int mask)
+{
+ struct inode *inode = path->dentry->d_inode;
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ return security_ops->path_permission(path, mask);
+}
+
int security_task_create(unsigned long clone_flags)
{
return security_ops->task_create(clone_flags);