[PATCH] Remove security_inode_post_create/mkdir/symlink/mknod hooks

This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as
they are obsoleted by the new inode_init_security hook that enables atomic
inode security labeling.

If anyone sees any reason to retain these hooks, please speak now.  Also,
is anyone using the post_rename/link hooks; if not, those could also be
removed.
Signed-off-by: NStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

fs/namei.c

@@ -1316,10 +1316,8 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 		return error;
 	DQUOT_INIT(dir);
 	error = dir->i_op->create(dir, dentry, mode, nd);
-	if (!error) {
+	if (!error)
 		fsnotify_create(dir, dentry->d_name.name);
-		security_inode_post_create(dir, dentry, mode);
-	}
 	return error;
 }
 
@@ -1635,10 +1633,8 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 
 	DQUOT_INIT(dir);
 	error = dir->i_op->mknod(dir, dentry, mode, dev);
-	if (!error) {
+	if (!error)
 		fsnotify_create(dir, dentry->d_name.name);
-		security_inode_post_mknod(dir, dentry, mode, dev);
-	}
 	return error;
 }
 
@@ -1708,10 +1704,8 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
 	DQUOT_INIT(dir);
 	error = dir->i_op->mkdir(dir, dentry, mode);
-	if (!error) {
+	if (!error)
 		fsnotify_mkdir(dir, dentry->d_name.name);
-		security_inode_post_mkdir(dir,dentry, mode);
-	}
 	return error;
 }
 
@@ -1947,10 +1941,8 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, i
 
 	DQUOT_INIT(dir);
 	error = dir->i_op->symlink(dir, dentry, oldname);
-	if (!error) {
+	if (!error)
 		fsnotify_create(dir, dentry->d_name.name);
-		security_inode_post_symlink(dir, dentry, oldname);
-	}
 	return error;
 }
 

include/linux/security.h

@@ -275,12 +275,6 @@ struct swap_info_struct;
  *	@dentry contains the dentry structure for the file to be created.
  *	@mode contains the file mode of the file to be created.
  *	Return 0 if permission is granted.
- * @inode_post_create:
- *	Set the security attributes on a newly created regular file.  This hook
- *	is called after a file has been successfully created.
- *	@dir contains the inode structure of the parent directory of the new file.
- *	@dentry contains the the dentry structure for the newly created file.
- *	@mode contains the file mode.
  * @inode_link:
  *	Check permission before creating a new hard link to a file.
  *	@old_dentry contains the dentry structure for an existing link to the file.
@@ -303,13 +297,6 @@ struct swap_info_struct;
  *	@dentry contains the dentry structure of the symbolic link.
  *	@old_name contains the pathname of file.
  *	Return 0 if permission is granted.
- * @inode_post_symlink:
- *	@dir contains the inode structure of the parent directory of the new link.
- *	@dentry contains the dentry structure of new symbolic link.
- *	@old_name contains the pathname of file.
- *	Set security attributes for a newly created symbolic link.  Note that
- *	@dentry->d_inode may be NULL, since the filesystem might not
- *	instantiate the dentry (e.g. NFS).
  * @inode_mkdir:
  *	Check permissions to create a new directory in the existing directory
  *	associated with inode strcture @dir. 
@@ -317,11 +304,6 @@ struct swap_info_struct;
  *	@dentry contains the dentry structure of new directory.
  *	@mode contains the mode of new directory.
  *	Return 0 if permission is granted.
- * @inode_post_mkdir:
- *	Set security attributes on a newly created directory.
- *	@dir contains the inode structure of parent of the directory to be created.
- *	@dentry contains the dentry structure of new directory.
- *	@mode contains the mode of new directory.
  * @inode_rmdir:
  *	Check the permission to remove a directory.
  *	@dir contains the inode structure of parent of the directory to be removed.
@@ -337,13 +319,6 @@ struct swap_info_struct;
  *	@mode contains the mode of the new file.
  *	@dev contains the the device number.
  *	Return 0 if permission is granted.
- * @inode_post_mknod:
- *	Set security attributes on a newly created special file (or socket or
- *	fifo file created via the mknod system call).
- *	@dir contains the inode structure of parent of the new node.
- *	@dentry contains the dentry structure of the new node.
- *	@mode contains the mode of the new node.
- *	@dev contains the the device number.
  * @inode_rename:
  *	Check for permission to rename a file or directory.
  *	@old_dir contains the inode structure for parent of the old link.
@@ -1103,8 +1078,6 @@ struct security_operations {
 				    char **name, void **value, size_t *len);
 	int (*inode_create) (struct inode *dir,
 	                     struct dentry *dentry, int mode);
-	void (*inode_post_create) (struct inode *dir,
-	                           struct dentry *dentry, int mode);
 	int (*inode_link) (struct dentry *old_dentry,
 	                   struct inode *dir, struct dentry *new_dentry);
 	void (*inode_post_link) (struct dentry *old_dentry,
@@ -1112,17 +1085,10 @@ struct security_operations {
 	int (*inode_unlink) (struct inode *dir, struct dentry *dentry);
 	int (*inode_symlink) (struct inode *dir,
 	                      struct dentry *dentry, const char *old_name);
-	void (*inode_post_symlink) (struct inode *dir,
-	                            struct dentry *dentry,
-	                            const char *old_name);
 	int (*inode_mkdir) (struct inode *dir, struct dentry *dentry, int mode);
-	void (*inode_post_mkdir) (struct inode *dir, struct dentry *dentry, 
-			    int mode);
 	int (*inode_rmdir) (struct inode *dir, struct dentry *dentry);
 	int (*inode_mknod) (struct inode *dir, struct dentry *dentry,
 	                    int mode, dev_t dev);
-	void (*inode_post_mknod) (struct inode *dir, struct dentry *dentry,
-	                          int mode, dev_t dev);
 	int (*inode_rename) (struct inode *old_dir, struct dentry *old_dentry,
 	                     struct inode *new_dir, struct dentry *new_dentry);
 	void (*inode_post_rename) (struct inode *old_dir,
@@ -1484,15 +1450,6 @@ static inline int security_inode_create (struct inode *dir,
 	return security_ops->inode_create (dir, dentry, mode);
 }
 
-static inline void security_inode_post_create (struct inode *dir,
-					       struct dentry *dentry,
-					       int mode)
-{
-	if (dentry->d_inode && unlikely (IS_PRIVATE (dentry->d_inode)))
-		return;
-	security_ops->inode_post_create (dir, dentry, mode);
-}
-
 static inline int security_inode_link (struct dentry *old_dentry,
 				       struct inode *dir,
 				       struct dentry *new_dentry)
@@ -1528,15 +1485,6 @@ static inline int security_inode_symlink (struct inode *dir,
 	return security_ops->inode_symlink (dir, dentry, old_name);
 }
 
-static inline void security_inode_post_symlink (struct inode *dir,
-						struct dentry *dentry,
-						const char *old_name)
-{
-	if (dentry->d_inode && unlikely (IS_PRIVATE (dentry->d_inode)))
-		return;
-	security_ops->inode_post_symlink (dir, dentry, old_name);
-}
-
 static inline int security_inode_mkdir (struct inode *dir,
 					struct dentry *dentry,
 					int mode)
@@ -1546,15 +1494,6 @@ static inline int security_inode_mkdir (struct inode *dir,
 	return security_ops->inode_mkdir (dir, dentry, mode);
 }
 
-static inline void security_inode_post_mkdir (struct inode *dir,
-					      struct dentry *dentry,
-					      int mode)
-{
-	if (dentry->d_inode && unlikely (IS_PRIVATE (dentry->d_inode)))
-		return;
-	security_ops->inode_post_mkdir (dir, dentry, mode);
-}
-
 static inline int security_inode_rmdir (struct inode *dir,
 					struct dentry *dentry)
 {
@@ -1572,15 +1511,6 @@ static inline int security_inode_mknod (struct inode *dir,
 	return security_ops->inode_mknod (dir, dentry, mode, dev);
 }
 
-static inline void security_inode_post_mknod (struct inode *dir,
-					      struct dentry *dentry,
-					      int mode, dev_t dev)
-{
-	if (dentry->d_inode && unlikely (IS_PRIVATE (dentry->d_inode)))
-		return;
-	security_ops->inode_post_mknod (dir, dentry, mode, dev);
-}
-
 static inline int security_inode_rename (struct inode *old_dir,
 					 struct dentry *old_dentry,
 					 struct inode *new_dir,
@@ -2220,11 +2150,6 @@ static inline int security_inode_create (struct inode *dir,
 	return 0;
 }
 
-static inline void security_inode_post_create (struct inode *dir,
-					       struct dentry *dentry,
-					       int mode)
-{ }
-
 static inline int security_inode_link (struct dentry *old_dentry,
 				       struct inode *dir,
 				       struct dentry *new_dentry)
@@ -2250,11 +2175,6 @@ static inline int security_inode_symlink (struct inode *dir,
 	return 0;
 }
 
-static inline void security_inode_post_symlink (struct inode *dir,
-						struct dentry *dentry,
-						const char *old_name)
-{ }
-
 static inline int security_inode_mkdir (struct inode *dir,
 					struct dentry *dentry,
 					int mode)
@@ -2262,11 +2182,6 @@ static inline int security_inode_mkdir (struct inode *dir,
 	return 0;
 }
 
-static inline void security_inode_post_mkdir (struct inode *dir,
-					      struct dentry *dentry,
-					      int mode)
-{ }
-
 static inline int security_inode_rmdir (struct inode *dir,
 					struct dentry *dentry)
 {
@@ -2280,11 +2195,6 @@ static inline int security_inode_mknod (struct inode *dir,
 	return 0;
 }
 
-static inline void security_inode_post_mknod (struct inode *dir,
-					      struct dentry *dentry,
-					      int mode, dev_t dev)
-{ }
-
 static inline int security_inode_rename (struct inode *old_dir,
 					 struct dentry *old_dentry,
 					 struct inode *new_dir,

security/dummy.c

@@ -270,12 +270,6 @@ static int dummy_inode_create (struct inode *inode, struct dentry *dentry,
 	return 0;
 }
 
-static void dummy_inode_post_create (struct inode *inode, struct dentry *dentry,
-				     int mask)
-{
-	return;
-}
-
 static int dummy_inode_link (struct dentry *old_dentry, struct inode *inode,
 			     struct dentry *new_dentry)
 {
@@ -300,24 +294,12 @@ static int dummy_inode_symlink (struct inode *inode, struct dentry *dentry,
 	return 0;
 }
 
-static void dummy_inode_post_symlink (struct inode *inode,
-				      struct dentry *dentry, const char *name)
-{
-	return;
-}
-
 static int dummy_inode_mkdir (struct inode *inode, struct dentry *dentry,
 			      int mask)
 {
 	return 0;
 }
 
-static void dummy_inode_post_mkdir (struct inode *inode, struct dentry *dentry,
-				    int mask)
-{
-	return;
-}
-
 static int dummy_inode_rmdir (struct inode *inode, struct dentry *dentry)
 {
 	return 0;
@@ -329,12 +311,6 @@ static int dummy_inode_mknod (struct inode *inode, struct dentry *dentry,
 	return 0;
 }
 
-static void dummy_inode_post_mknod (struct inode *inode, struct dentry *dentry,
-				    int mode, dev_t dev)
-{
-	return;
-}
-
 static int dummy_inode_rename (struct inode *old_inode,
 			       struct dentry *old_dentry,
 			       struct inode *new_inode,
@@ -894,17 +870,13 @@ void security_fixup_ops (struct security_operations *ops)
 	set_to_dummy_if_null(ops, inode_free_security);
 	set_to_dummy_if_null(ops, inode_init_security);
 	set_to_dummy_if_null(ops, inode_create);
-	set_to_dummy_if_null(ops, inode_post_create);
 	set_to_dummy_if_null(ops, inode_link);
 	set_to_dummy_if_null(ops, inode_post_link);
 	set_to_dummy_if_null(ops, inode_unlink);
 	set_to_dummy_if_null(ops, inode_symlink);
-	set_to_dummy_if_null(ops, inode_post_symlink);
 	set_to_dummy_if_null(ops, inode_mkdir);
-	set_to_dummy_if_null(ops, inode_post_mkdir);
 	set_to_dummy_if_null(ops, inode_rmdir);
 	set_to_dummy_if_null(ops, inode_mknod);
-	set_to_dummy_if_null(ops, inode_post_mknod);
 	set_to_dummy_if_null(ops, inode_rename);
 	set_to_dummy_if_null(ops, inode_post_rename);
 	set_to_dummy_if_null(ops, inode_readlink);

security/selinux/hooks.c

@@ -1265,91 +1265,6 @@ static int inode_security_set_sid(struct inode *inode, u32 sid)
 	return 0;
 }
 
-/* Set the security attributes on a newly created file. */
-static int post_create(struct inode *dir,
-		       struct dentry *dentry)
-{
-
-	struct task_security_struct *tsec;
-	struct inode *inode;
-	struct inode_security_struct *dsec;
-	struct superblock_security_struct *sbsec;
-	struct inode_security_struct *isec;
-	u32 newsid;
-	char *context;
-	unsigned int len;
-	int rc;
-
-	tsec = current->security;
-	dsec = dir->i_security;
-	sbsec = dir->i_sb->s_security;
-
-	inode = dentry->d_inode;
-	if (!inode) {
-		/* Some file system types (e.g. NFS) may not instantiate
-		   a dentry for all create operations (e.g. symlink),
-		   so we have to check to see if the inode is non-NULL. */
-		printk(KERN_WARNING "post_create:  no inode, dir (dev=%s, "
-		       "ino=%ld)\n", dir->i_sb->s_id, dir->i_ino);
-		return 0;
-	}
-
-	isec = inode->i_security;
-
-	if (isec->security_attr_init)
-		return 0;
-
-	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
-		newsid = tsec->create_sid;
-	} else {
-		rc = security_transition_sid(tsec->sid, dsec->sid,
-					     inode_mode_to_security_class(inode->i_mode),
-					     &newsid);
-		if (rc) {
-			printk(KERN_WARNING "post_create:  "
-			       "security_transition_sid failed, rc=%d (dev=%s "
-			       "ino=%ld)\n",
-			       -rc, inode->i_sb->s_id, inode->i_ino);
-			return rc;
-		}
-	}
-
-	rc = inode_security_set_sid(inode, newsid);
-	if (rc) {
-		printk(KERN_WARNING "post_create:  inode_security_set_sid "
-		       "failed, rc=%d (dev=%s ino=%ld)\n",
-		       -rc, inode->i_sb->s_id, inode->i_ino);
-		return rc;
-	}
-
-	if (sbsec->behavior == SECURITY_FS_USE_XATTR &&
-	    inode->i_op->setxattr) {
-		/* Use extended attributes. */
-		rc = security_sid_to_context(newsid, &context, &len);
-		if (rc) {
-			printk(KERN_WARNING "post_create:  sid_to_context "
-			       "failed, rc=%d (dev=%s ino=%ld)\n",
-			       -rc, inode->i_sb->s_id, inode->i_ino);
-			return rc;
-		}
-		down(&inode->i_sem);
-		rc = inode->i_op->setxattr(dentry,
-					   XATTR_NAME_SELINUX,
-					   context, len, 0);
-		up(&inode->i_sem);
-		kfree(context);
-		if (rc < 0) {
-			printk(KERN_WARNING "post_create:  setxattr failed, "
-			       "rc=%d (dev=%s ino=%ld)\n",
-			       -rc, inode->i_sb->s_id, inode->i_ino);
-			return rc;
-		}
-	}
-
-	return 0;
-}
-
-
 /* Hook functions begin here. */
 
 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
@@ -2076,8 +1991,6 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
 		*len = clen;
 	}
 
-	isec->security_attr_init = 1;
-
 	return 0;
 }
 
@@ -2086,11 +1999,6 @@ static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int ma
 	return may_create(dir, dentry, SECCLASS_FILE);
 }
 
-static void selinux_inode_post_create(struct inode *dir, struct dentry *dentry, int mask)
-{
-	post_create(dir, dentry);
-}
-
 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
 {
 	int rc;
@@ -2121,21 +2029,11 @@ static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const
 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
 }
 
-static void selinux_inode_post_symlink(struct inode *dir, struct dentry *dentry, const char *name)
-{
-	post_create(dir, dentry);
-}
-
 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
 {
 	return may_create(dir, dentry, SECCLASS_DIR);
 }
 
-static void selinux_inode_post_mkdir(struct inode *dir, struct dentry *dentry, int mask)
-{
-	post_create(dir, dentry);
-}
-
 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	return may_link(dir, dentry, MAY_RMDIR);
@@ -2152,11 +2050,6 @@ static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mod
 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
 }
 
-static void selinux_inode_post_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
-{
-	post_create(dir, dentry);
-}
-
 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
                                 struct inode *new_inode, struct dentry *new_dentry)
 {
@@ -4363,17 +4256,13 @@ static struct security_operations selinux_ops = {
 	.inode_free_security =		selinux_inode_free_security,
 	.inode_init_security =		selinux_inode_init_security,
 	.inode_create =			selinux_inode_create,
-	.inode_post_create =		selinux_inode_post_create,
 	.inode_link =			selinux_inode_link,
 	.inode_post_link =		selinux_inode_post_link,
 	.inode_unlink =			selinux_inode_unlink,
 	.inode_symlink =		selinux_inode_symlink,
-	.inode_post_symlink =		selinux_inode_post_symlink,
 	.inode_mkdir =			selinux_inode_mkdir,
-	.inode_post_mkdir =		selinux_inode_post_mkdir,
 	.inode_rmdir =			selinux_inode_rmdir,
 	.inode_mknod =			selinux_inode_mknod,
-	.inode_post_mknod =		selinux_inode_post_mknod,
 	.inode_rename =			selinux_inode_rename,
 	.inode_post_rename =		selinux_inode_post_rename,
 	.inode_readlink =		selinux_inode_readlink,

security/selinux/include/objsec.h

@@ -46,7 +46,6 @@ struct inode_security_struct {
 	unsigned char initialized;     /* initialization flag */
 	struct semaphore sem;
 	unsigned char inherit;         /* inherit SID from parent entry */
-	unsigned char security_attr_init; /* security attributes init flag */
 };
 
 struct file_security_struct {