TOMOYO: Enable conditional ACL.

Enable conditional ACL by passing object's pointers.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

5 files changed, 80 insertions, 33 deletions

diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index 6c013b177791..f7fbaa66e443 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -836,7 +836,8 @@ int tomoyo_path2_perm(const u8 operation, struct path *path1,
 		      struct path *path2);
 int tomoyo_path_number_perm(const u8 operation, struct path *path,
 			    unsigned long number);
-int tomoyo_path_perm(const u8 operation, struct path *path);
+int tomoyo_path_perm(const u8 operation, struct path *path,
+		     const char *target);
 int tomoyo_path_permission(struct tomoyo_request_info *r, u8 operation,
 			   const struct tomoyo_path_info *filename);
 int tomoyo_poll_control(struct file *file, poll_table *wait);
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
index 565249c42e39..878d0206f43e 100644
--- a/security/tomoyo/domain.c
+++ b/security/tomoyo/domain.c
@@ -575,23 +575,27 @@ out:
  */
 int tomoyo_find_next_domain(struct linux_binprm *bprm)
 {
-	struct tomoyo_request_info r;
-	char *tmp = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
 	struct tomoyo_domain_info *old_domain = tomoyo_domain();
 	struct tomoyo_domain_info *domain = NULL;
 	const char *original_name = bprm->filename;
-	u8 mode;
-	bool is_enforce;
 	int retval = -ENOMEM;
 	bool need_kfree = false;
 	bool reject_on_transition_failure = false;
 	struct tomoyo_path_info rn = { }; /* real name */
-
-	mode = tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_EXECUTE);
-	is_enforce = (mode == TOMOYO_CONFIG_ENFORCING);
-	if (!tmp)
-		goto out;
-
+	struct tomoyo_execve *ee = kzalloc(sizeof(*ee), GFP_NOFS);
+	if (!ee)
+		return -ENOMEM;
+	ee->tmp = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
+	if (!ee->tmp) {
+		kfree(ee);
+		return -ENOMEM;
+	}
+	/* ee->dump->data is allocated by tomoyo_dump_page(). */
+	tomoyo_init_request_info(&ee->r, NULL, TOMOYO_MAC_FILE_EXECUTE);
+	ee->r.ee = ee;
+	ee->bprm = bprm;
+	ee->r.obj = &ee->obj;
+	ee->obj.path1 = bprm->file->f_path;
  retry:
 	if (need_kfree) {
 		kfree(rn.name);
@@ -625,7 +629,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 	}
 
 	/* Check execute permission. */
-	retval = tomoyo_path_permission(&r, TOMOYO_TYPE_EXECUTE, &rn);
+	retval = tomoyo_path_permission(&ee->r, TOMOYO_TYPE_EXECUTE, &rn);
 	if (retval == TOMOYO_RETRY_REQUEST)
 		goto retry;
 	if (retval < 0)
@@ -636,12 +640,12 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 	 * wildcard) rather than the pathname passed to execve()
 	 * (which never contains wildcard).
 	 */
-	if (r.param.path.matched_path) {
+	if (ee->r.param.path.matched_path) {
 		if (need_kfree)
 			kfree(rn.name);
 		need_kfree = false;
 		/* This is OK because it is read only. */
-		rn = *r.param.path.matched_path;
+		rn = *ee->r.param.path.matched_path;
 	}
 
 	/* Calculate domain to transit to. */
@@ -649,7 +653,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 				       &rn)) {
 	case TOMOYO_TRANSITION_CONTROL_RESET:
 		/* Transit to the root of specified namespace. */
-		snprintf(tmp, TOMOYO_EXEC_TMPSIZE - 1, "<%s>", rn.name);
+		snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "<%s>", rn.name);
 		/*
 		 * Make do_execve() fail if domain transition across namespaces
 		 * has failed.
@@ -658,7 +662,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 		break;
 	case TOMOYO_TRANSITION_CONTROL_INITIALIZE:
 		/* Transit to the child of current namespace's root. */
-		snprintf(tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
+		snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
 			 old_domain->ns->name, rn.name);
 		break;
 	case TOMOYO_TRANSITION_CONTROL_KEEP:
@@ -677,29 +681,30 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 			domain = old_domain;
 		} else {
 			/* Normal domain transition. */
-			snprintf(tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
+			snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
 				 old_domain->domainname->name, rn.name);
 		}
 		break;
 	}
 	if (!domain)
-		domain = tomoyo_assign_domain(tmp, true);
+		domain = tomoyo_assign_domain(ee->tmp, true);
 	if (domain)
 		retval = 0;
 	else if (reject_on_transition_failure) {
-		printk(KERN_WARNING "ERROR: Domain '%s' not ready.\n", tmp);
+		printk(KERN_WARNING "ERROR: Domain '%s' not ready.\n",
+		       ee->tmp);
 		retval = -ENOMEM;
-	} else if (r.mode == TOMOYO_CONFIG_ENFORCING)
+	} else if (ee->r.mode == TOMOYO_CONFIG_ENFORCING)
 		retval = -ENOMEM;
 	else {
 		retval = 0;
 		if (!old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED]) {
 			old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED] = true;
-			r.granted = false;
-			tomoyo_write_log(&r, "%s", tomoyo_dif
+			ee->r.granted = false;
+			tomoyo_write_log(&ee->r, "%s", tomoyo_dif
 					 [TOMOYO_DIF_TRANSITION_FAILED]);
 			printk(KERN_WARNING
-			       "ERROR: Domain '%s' not defined.\n", tmp);
+			       "ERROR: Domain '%s' not defined.\n", ee->tmp);
 		}
 	}
  out:
@@ -710,7 +715,9 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
 	bprm->cred->security = domain;
 	if (need_kfree)
 		kfree(rn.name);
-	kfree(tmp);
+	kfree(ee->tmp);
+	kfree(ee->dump.data);
+	kfree(ee);
 	return retval;
 }
 
diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c
index 6ab9e4cdd61f..31a9a4ab7af9 100644
--- a/security/tomoyo/file.c
+++ b/security/tomoyo/file.c
@@ -667,6 +667,9 @@ int tomoyo_path_number_perm(const u8 type, struct path *path,
 			    unsigned long number)
 {
 	struct tomoyo_request_info r;
+	struct tomoyo_obj_info obj = {
+		.path1 = *path,
+	};
 	int error = -ENOMEM;
 	struct tomoyo_path_info buf;
 	int idx;
@@ -677,6 +680,7 @@ int tomoyo_path_number_perm(const u8 type, struct path *path,
 	idx = tomoyo_read_lock();
 	if (!tomoyo_get_realpath(&buf, path))
 		goto out;
+	r.obj = &obj;
 	if (type == TOMOYO_TYPE_MKDIR)
 		tomoyo_add_slash(&buf);
 	r.param_type = TOMOYO_TYPE_PATH_NUMBER_ACL;
@@ -711,6 +715,9 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
 	int error = 0;
 	struct tomoyo_path_info buf;
 	struct tomoyo_request_info r;
+	struct tomoyo_obj_info obj = {
+		.path1 = *path,
+	};
 	int idx;
 
 	buf.name = NULL;
@@ -723,6 +730,7 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
 			error = -ENOMEM;
 			goto out;
 		}
+		r.obj = &obj;
 		if (acc_mode & MAY_READ)
 			error = tomoyo_path_permission(&r, TOMOYO_TYPE_READ,
 						       &buf);
@@ -745,15 +753,21 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
  *
  * @operation: Type of operation.
  * @path:      Pointer to "struct path".
+ * @target:    Symlink's target if @operation is TOMOYO_TYPE_SYMLINK,
+ *             NULL otherwise.
  *
  * Returns 0 on success, negative value otherwise.
  */
-int tomoyo_path_perm(const u8 operation, struct path *path)
+int tomoyo_path_perm(const u8 operation, struct path *path, const char *target)
 {
 	struct tomoyo_request_info r;
+	struct tomoyo_obj_info obj = {
+		.path1 = *path,
+	};
 	int error;
 	struct tomoyo_path_info buf;
 	bool is_enforce;
+	struct tomoyo_path_info symlink_target;
 	int idx;
 
 	if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation])
@@ -765,13 +779,23 @@ int tomoyo_path_perm(const u8 operation, struct path *path)
 	idx = tomoyo_read_lock();
 	if (!tomoyo_get_realpath(&buf, path))
 		goto out;
+	r.obj = &obj;
 	switch (operation) {
 	case TOMOYO_TYPE_RMDIR:
 	case TOMOYO_TYPE_CHROOT:
 		tomoyo_add_slash(&buf);
 		break;
+	case TOMOYO_TYPE_SYMLINK:
+		symlink_target.name = tomoyo_encode(target);
+		if (!symlink_target.name)
+			goto out;
+		tomoyo_fill_path_info(&symlink_target);
+		obj.symlink_target = &symlink_target;
+		break;
 	}
 	error = tomoyo_path_permission(&r, operation, &buf);
+	if (operation == TOMOYO_TYPE_SYMLINK)
+		kfree(symlink_target.name);
  out:
 	kfree(buf.name);
 	tomoyo_read_unlock(idx);
@@ -794,6 +818,9 @@ int tomoyo_mkdev_perm(const u8 operation, struct path *path,
 		      const unsigned int mode, unsigned int dev)
 {
 	struct tomoyo_request_info r;
+	struct tomoyo_obj_info obj = {
+		.path1 = *path,
+	};
 	int error = -ENOMEM;
 	struct tomoyo_path_info buf;
 	int idx;
@@ -804,6 +831,7 @@ int tomoyo_mkdev_perm(const u8 operation, struct path *path,
 	idx = tomoyo_read_lock();
 	error = -ENOMEM;
 	if (tomoyo_get_realpath(&buf, path)) {
+		r.obj = &obj;
 		dev = new_decode_dev(dev);
 		r.param_type = TOMOYO_TYPE_MKDEV_ACL;
 		r.param.mkdev.filename = &buf;
@@ -837,6 +865,10 @@ int tomoyo_path2_perm(const u8 operation, struct path *path1,
 	struct tomoyo_path_info buf1;
 	struct tomoyo_path_info buf2;
 	struct tomoyo_request_info r;
+	struct tomoyo_obj_info obj = {
+		.path1 = *path1,
+		.path2 = *path2,
+	};
 	int idx;
 
 	if (tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation])
@@ -861,6 +893,7 @@ int tomoyo_path2_perm(const u8 operation, struct path *path1,
                 tomoyo_add_slash(&buf2);
 		break;
         }
+	r.obj = &obj;
 	r.param_type = TOMOYO_TYPE_PATH2_ACL;
 	r.param.path2.operation = operation;
 	r.param.path2.filename1 = &buf1;
diff --git a/security/tomoyo/mount.c b/security/tomoyo/mount.c
index 0bbba8b67821..408385307470 100644
--- a/security/tomoyo/mount.c
+++ b/security/tomoyo/mount.c
@@ -75,6 +75,7 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
 			    struct path *dir, const char *type,
 			    unsigned long flags)
 {
+	struct tomoyo_obj_info obj = { };
 	struct path path;
 	struct file_system_type *fstype = NULL;
 	const char *requested_type = NULL;
@@ -85,6 +86,7 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
 	struct tomoyo_path_info rdir;
 	int need_dev = 0;
 	int error = -ENOMEM;
+	r->obj = &obj;
 
 	/* Get fstype. */
 	requested_type = tomoyo_encode(type);
@@ -94,6 +96,7 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
 	tomoyo_fill_path_info(&rtype);
 
 	/* Get mount point. */
+	obj.path2 = *dir;
 	requested_dir_name = tomoyo_realpath_from_path(dir);
 	if (!requested_dir_name) {
 		error = -ENOMEM;
@@ -129,8 +132,8 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
 			error = -ENOENT;
 			goto out;
 		}
+		obj.path1 = path;
 		requested_dev_name = tomoyo_realpath_from_path(&path);
-		path_put(&path);
 		if (!requested_dev_name) {
 			error = -ENOENT;
 			goto out;
@@ -163,6 +166,9 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
 	if (fstype)
 		put_filesystem(fstype);
 	kfree(requested_type);
+	/* Drop refcount obtained by kern_path(). */
+	if (obj.path1.dentry)
+		path_put(&obj.path1);
 	return error;
 }
 
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index d6f68a0ec2dc..a536cb182c05 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -98,18 +98,18 @@ static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
 static int tomoyo_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
 {
 	struct path path = { mnt, dentry };
-	return tomoyo_path_perm(TOMOYO_TYPE_GETATTR, &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_GETATTR, &path, NULL);
 }
 
 static int tomoyo_path_truncate(struct path *path)
 {
-	return tomoyo_path_perm(TOMOYO_TYPE_TRUNCATE, path);
+	return tomoyo_path_perm(TOMOYO_TYPE_TRUNCATE, path, NULL);
 }
 
 static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_path_perm(TOMOYO_TYPE_UNLINK, &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_UNLINK, &path, NULL);
 }
 
 static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry,
@@ -123,14 +123,14 @@ static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry,
 static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_path_perm(TOMOYO_TYPE_RMDIR, &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_RMDIR, &path, NULL);
 }
 
 static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry,
 			       const char *old_name)
 {
 	struct path path = { parent->mnt, dentry };
-	return tomoyo_path_perm(TOMOYO_TYPE_SYMLINK, &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_SYMLINK, &path, old_name);
 }
 
 static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry,
@@ -225,7 +225,7 @@ static int tomoyo_path_chown(struct path *path, uid_t uid, gid_t gid)
 
 static int tomoyo_path_chroot(struct path *path)
 {
-	return tomoyo_path_perm(TOMOYO_TYPE_CHROOT, path);
+	return tomoyo_path_perm(TOMOYO_TYPE_CHROOT, path, NULL);
 }
 
 static int tomoyo_sb_mount(char *dev_name, struct path *path,
@@ -237,7 +237,7 @@ static int tomoyo_sb_mount(char *dev_name, struct path *path,
 static int tomoyo_sb_umount(struct vfsmount *mnt, int flags)
 {
 	struct path path = { mnt, mnt->mnt_root };
-	return tomoyo_path_perm(TOMOYO_TYPE_UMOUNT, &path);
+	return tomoyo_path_perm(TOMOYO_TYPE_UMOUNT, &path, NULL);
 }
 
 static int tomoyo_sb_pivotroot(struct path *old_path, struct path *new_path)