Linux-libre 4.1.5-gnupck-4.1.5-gnu

8 files changed, 75 insertions, 41 deletions

diff --git a/ipc/kdbus/bus.h b/ipc/kdbus/bus.h
index 238986eff..8c2acaed6 100644
--- a/ipc/kdbus/bus.h
+++ b/ipc/kdbus/bus.h
@@ -44,6 +44,7 @@ struct kdbus_user;
  * @domain:		Domain of this bus
  * @creator:		Creator of the bus
  * @creator_meta:	Meta information about the bus creator
+ * @last_message_id:	Last used message id
  * @policy_db:		Policy database for this bus
  * @name_registry:	Name registry of this bus
  * @conn_rwlock:	Read/Write lock for all lists of child connections
@@ -67,6 +68,7 @@ struct kdbus_bus {
 	struct kdbus_meta_proc *creator_meta;
 
 	/* protected by own locks */
+	atomic64_t last_message_id;
 	struct kdbus_policy_db policy_db;
 	struct kdbus_name_registry *name_registry;
 
diff --git a/ipc/kdbus/connection.c b/ipc/kdbus/connection.c
index d94b417e0..aa3296ea4 100644
--- a/ipc/kdbus/connection.c
+++ b/ipc/kdbus/connection.c
@@ -52,7 +52,8 @@
 #define KDBUS_CONN_ACTIVE_BIAS	(INT_MIN + 2)
 #define KDBUS_CONN_ACTIVE_NEW	(INT_MIN + 1)
 
-static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
+static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep,
+					 struct file *file,
 					 struct kdbus_cmd_hello *hello,
 					 const char *name,
 					 const struct kdbus_creds *creds,
@@ -72,6 +73,8 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
 	bool is_policy_holder;
 	bool is_activator;
 	bool is_monitor;
+	bool privileged;
+	bool owner;
 	struct kvec kvec;
 	int ret;
 
@@ -81,6 +84,9 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
 		struct kdbus_bloom_parameter bloom;
 	} bloom_item;
 
+	privileged = kdbus_ep_is_privileged(ep, file);
+	owner = kdbus_ep_is_owner(ep, file);
+
 	is_monitor = hello->flags & KDBUS_HELLO_MONITOR;
 	is_activator = hello->flags & KDBUS_HELLO_ACTIVATOR;
 	is_policy_holder = hello->flags & KDBUS_HELLO_POLICY_HOLDER;
@@ -97,9 +103,9 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
 		return ERR_PTR(-EINVAL);
 	if (is_monitor && ep->user)
 		return ERR_PTR(-EOPNOTSUPP);
-	if (!privileged && (is_activator || is_policy_holder || is_monitor))
+	if (!owner && (is_activator || is_policy_holder || is_monitor))
 		return ERR_PTR(-EPERM);
-	if ((creds || pids || seclabel) && !privileged)
+	if (!owner && (creds || pids || seclabel))
 		return ERR_PTR(-EPERM);
 
 	ret = kdbus_sanitize_attach_flags(hello->attach_flags_send,
@@ -129,12 +135,13 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
 	atomic_set(&conn->request_count, 0);
 	atomic_set(&conn->lost_count, 0);
 	INIT_DELAYED_WORK(&conn->work, kdbus_reply_list_scan_work);
-	conn->cred = get_current_cred();
+	conn->cred = get_cred(file->f_cred);
 	conn->pid = get_pid(task_pid(current));
 	get_fs_root(current->fs, &conn->root_path);
 	init_waitqueue_head(&conn->wait);
 	kdbus_queue_init(&conn->queue);
 	conn->privileged = privileged;
+	conn->owner = owner;
 	conn->ep = kdbus_ep_ref(ep);
 	conn->id = atomic64_inc_return(&bus->domain->last_id);
 	conn->flags = hello->flags;
@@ -214,11 +221,21 @@ static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged,
 	 * Note that limits are always accounted against the real UID, not
 	 * the effective UID (cred->user always points to the accounting of
 	 * cred->uid, not cred->euid).
+	 * In case the caller is privileged, we allow changing the accounting
+	 * to the faked user.
 	 */
 	if (ep->user) {
 		conn->user = kdbus_user_ref(ep->user);
 	} else {
-		conn->user = kdbus_user_lookup(ep->bus->domain, current_uid());
+		kuid_t uid;
+
+		if (conn->meta_fake && uid_valid(conn->meta_fake->uid) &&
+		    conn->privileged)
+			uid = conn->meta_fake->uid;
+		else
+			uid = conn->cred->uid;
+
+		conn->user = kdbus_user_lookup(ep->bus->domain, uid);
 		if (IS_ERR(conn->user)) {
 			ret = PTR_ERR(conn->user);
 			conn->user = NULL;
@@ -1123,7 +1140,7 @@ static int kdbus_conn_reply(struct kdbus_conn *src,
 	mutex_unlock(&dst->lock);
 
 	if (!reply) {
-		ret = -EPERM;
+		ret = -EBADSLT;
 		goto exit;
 	}
 
@@ -1418,7 +1435,7 @@ bool kdbus_conn_policy_own_name(struct kdbus_conn *conn,
 			return false;
 	}
 
-	if (conn->privileged)
+	if (conn->owner)
 		return true;
 
 	res = kdbus_policy_query(&conn->ep->bus->policy_db, conn_creds,
@@ -1448,7 +1465,7 @@ bool kdbus_conn_policy_talk(struct kdbus_conn *conn,
 					 to, KDBUS_POLICY_TALK))
 		return false;
 
-	if (conn->privileged)
+	if (conn->owner)
 		return true;
 	if (uid_eq(conn_creds->euid, to->cred->uid))
 		return true;
@@ -1567,12 +1584,12 @@ bool kdbus_conn_policy_see_notification(struct kdbus_conn *conn,
 /**
  * kdbus_cmd_hello() - handle KDBUS_CMD_HELLO
  * @ep:			Endpoint to operate on
- * @privileged:		Whether the caller is privileged
+ * @file:		File this connection is opened on
  * @argp:		Command payload
  *
  * Return: NULL or newly created connection on success, ERR_PTR on failure.
  */
-struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged,
+struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, struct file *file,
 				   void __user *argp)
 {
 	struct kdbus_cmd_hello *cmd;
@@ -1607,7 +1624,7 @@ struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged,
 
 	item_name = argv[1].item ? argv[1].item->str : NULL;
 
-	c = kdbus_conn_new(ep, privileged, cmd, item_name,
+	c = kdbus_conn_new(ep, file, cmd, item_name,
 			   argv[2].item ? &argv[2].item->creds : NULL,
 			   argv[3].item ? &argv[3].item->pids : NULL,
 			   argv[4].item ? argv[4].item->str : NULL,
diff --git a/ipc/kdbus/connection.h b/ipc/kdbus/connection.h
index 5ee864eb0..8e0180ace 100644
--- a/ipc/kdbus/connection.h
+++ b/ipc/kdbus/connection.h
@@ -73,7 +73,8 @@ struct kdbus_staging;
  * @activator_of:	Well-known name entry this connection acts as an
  * @names_list:		List of well-known names
  * @names_queue_list:	Well-known names this connection waits for
- * @privileged:		Whether this connection is privileged on the bus
+ * @privileged:		Whether this connection is privileged on the domain
+ * @owner:		Owned by the same user as the bus owner
  */
 struct kdbus_conn {
 	struct kref kref;
@@ -116,6 +117,7 @@ struct kdbus_conn {
 	struct list_head names_queue_list;
 
 	bool privileged:1;
+	bool owner:1;
 };
 
 struct kdbus_conn *kdbus_conn_ref(struct kdbus_conn *conn);
@@ -154,7 +156,7 @@ bool kdbus_conn_policy_see_notification(struct kdbus_conn *conn,
 					const struct kdbus_msg *msg);
 
 /* command dispatcher */
-struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged,
+struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, struct file *file,
 				   void __user *argp);
 int kdbus_cmd_byebye_unlocked(struct kdbus_conn *conn, void __user *argp);
 int kdbus_cmd_conn_info(struct kdbus_conn *conn, void __user *argp);
diff --git a/ipc/kdbus/endpoint.c b/ipc/kdbus/endpoint.c
index 977964dbb..44e7a20de 100644
--- a/ipc/kdbus/endpoint.c
+++ b/ipc/kdbus/endpoint.c
@@ -184,6 +184,34 @@ struct kdbus_ep *kdbus_ep_unref(struct kdbus_ep *ep)
 }
 
 /**
+ * kdbus_ep_is_privileged() - check whether a file is privileged
+ * @ep:		endpoint to operate on
+ * @file:	file to test
+ *
+ * Return: True if @file is privileged in the domain of @ep.
+ */
+bool kdbus_ep_is_privileged(struct kdbus_ep *ep, struct file *file)
+{
+	return !ep->user &&
+		file_ns_capable(file, ep->bus->domain->user_namespace,
+				CAP_IPC_OWNER);
+}
+
+/**
+ * kdbus_ep_is_owner() - check whether a file should be treated as bus owner
+ * @ep:		endpoint to operate on
+ * @file:	file to test
+ *
+ * Return: True if @file should be treated as bus owner on @ep
+ */
+bool kdbus_ep_is_owner(struct kdbus_ep *ep, struct file *file)
+{
+	return !ep->user &&
+		(uid_eq(file->f_cred->euid, ep->bus->node.uid) ||
+		 kdbus_ep_is_privileged(ep, file));
+}
+
+/**
  * kdbus_cmd_ep_make() - handle KDBUS_CMD_ENDPOINT_MAKE
  * @bus:		bus to operate on
  * @argp:		command payload
diff --git a/ipc/kdbus/endpoint.h b/ipc/kdbus/endpoint.h
index bc1b94a70..e0da59f01 100644
--- a/ipc/kdbus/endpoint.h
+++ b/ipc/kdbus/endpoint.h
@@ -61,6 +61,9 @@ struct kdbus_ep *kdbus_ep_new(struct kdbus_bus *bus, const char *name,
 struct kdbus_ep *kdbus_ep_ref(struct kdbus_ep *ep);
 struct kdbus_ep *kdbus_ep_unref(struct kdbus_ep *ep);
 
+bool kdbus_ep_is_privileged(struct kdbus_ep *ep, struct file *file);
+bool kdbus_ep_is_owner(struct kdbus_ep *ep, struct file *file);
+
 struct kdbus_ep *kdbus_cmd_ep_make(struct kdbus_bus *bus, void __user *argp);
 int kdbus_cmd_ep_update(struct kdbus_ep *ep, void __user *argp);
 
diff --git a/ipc/kdbus/handle.c b/ipc/kdbus/handle.c
index e0e06b0e1..fc60932d6 100644
--- a/ipc/kdbus/handle.c
+++ b/ipc/kdbus/handle.c
@@ -264,7 +264,6 @@ enum kdbus_handle_type {
  * @bus_owner:		bus this handle owns
  * @ep_owner:		endpoint this handle owns
  * @conn:		connection this handle owns
- * @privileged:		Flag to mark a handle as privileged
  */
 struct kdbus_handle {
 	struct mutex lock;
@@ -275,8 +274,6 @@ struct kdbus_handle {
 		struct kdbus_ep *ep_owner;
 		struct kdbus_conn *conn;
 	};
-
-	bool privileged:1;
 };
 
 static int kdbus_handle_open(struct inode *inode, struct file *file)
@@ -298,23 +295,6 @@ static int kdbus_handle_open(struct inode *inode, struct file *file)
 	mutex_init(&handle->lock);
 	handle->type = KDBUS_HANDLE_NONE;
 
-	if (node->type == KDBUS_NODE_ENDPOINT) {
-		struct kdbus_ep *ep = kdbus_ep_from_node(node);
-		struct kdbus_bus *bus = ep->bus;
-
-		/*
-		 * A connection is privileged if it is opened on an endpoint
-		 * without custom policy and either:
-		 *   * the user has CAP_IPC_OWNER in the domain user namespace
-		 * or
-		 *   * the callers euid matches the uid of the bus creator
-		 */
-		if (!ep->user &&
-		    (ns_capable(bus->domain->user_namespace, CAP_IPC_OWNER) ||
-		     uid_eq(file->f_cred->euid, bus->node.uid)))
-			handle->privileged = true;
-	}
-
 	file->private_data = handle;
 	ret = 0;
 
@@ -406,6 +386,7 @@ static long kdbus_handle_ioctl_ep(struct file *file, unsigned int cmd,
 	struct kdbus_handle *handle = file->private_data;
 	struct kdbus_node *node = file_inode(file)->i_private;
 	struct kdbus_ep *ep, *file_ep = kdbus_ep_from_node(node);
+	struct kdbus_bus *bus = file_ep->bus;
 	struct kdbus_conn *conn;
 	int ret = 0;
 
@@ -413,14 +394,14 @@ static long kdbus_handle_ioctl_ep(struct file *file, unsigned int cmd,
 		return -ESHUTDOWN;
 
 	switch (cmd) {
-	case KDBUS_CMD_ENDPOINT_MAKE:
+	case KDBUS_CMD_ENDPOINT_MAKE: {
 		/* creating custom endpoints is a privileged operation */
-		if (!handle->privileged) {
+		if (!kdbus_ep_is_owner(file_ep, file)) {
 			ret = -EPERM;
 			break;
 		}
 
-		ep = kdbus_cmd_ep_make(file_ep->bus, buf);
+		ep = kdbus_cmd_ep_make(bus, buf);
 		if (IS_ERR_OR_NULL(ep)) {
 			ret = PTR_ERR_OR_ZERO(ep);
 			break;
@@ -429,9 +410,10 @@ static long kdbus_handle_ioctl_ep(struct file *file, unsigned int cmd,
 		handle->ep_owner = ep;
 		ret = KDBUS_HANDLE_EP_OWNER;
 		break;
+	}
 
 	case KDBUS_CMD_HELLO:
-		conn = kdbus_cmd_hello(file_ep, handle->privileged, buf);
+		conn = kdbus_cmd_hello(file_ep, file, buf);
 		if (IS_ERR_OR_NULL(conn)) {
 			ret = PTR_ERR_OR_ZERO(conn);
 			break;
diff --git a/ipc/kdbus/handle.h b/ipc/kdbus/handle.h
index 8a36c0595..5dde2c10b 100644
--- a/ipc/kdbus/handle.h
+++ b/ipc/kdbus/handle.h
@@ -45,7 +45,7 @@ struct kdbus_arg {
  * @argv:		array of items this command supports
  * @user:		set by parser to user-space location of current command
  * @cmd:		set by parser to kernel copy of command payload
- * @cmd_buf:		512 bytes inline buf to avoid kmalloc() on small cmds
+ * @cmd_buf:		inline buf to avoid kmalloc() on small cmds
  * @items:		points to item array in @cmd
  * @items_size:		size of @items in bytes
  * @is_cmd:		whether this is a command-payload or msg-payload
@@ -55,7 +55,7 @@ struct kdbus_arg {
  * the object to kdbus_args_parse(). The parser will copy the command payload
  * into kernel-space and verify the correctness of the data.
  *
- * We use a 512 bytes buffer for small command payloads, to be allocated on
+ * We use a 256 bytes buffer for small command payloads, to be allocated on
  * stack on syscall entrance.
  */
 struct kdbus_args {
@@ -65,7 +65,7 @@ struct kdbus_args {
 
 	struct kdbus_cmd __user *user;
 	struct kdbus_cmd *cmd;
-	u8 cmd_buf[512];
+	u8 cmd_buf[256];
 
 	struct kdbus_item *items;
 	size_t items_size;
diff --git a/ipc/kdbus/message.c b/ipc/kdbus/message.c
index 432dba4dc..ae565cd34 100644
--- a/ipc/kdbus/message.c
+++ b/ipc/kdbus/message.c
@@ -671,7 +671,7 @@ static struct kdbus_staging *kdbus_staging_new(struct kdbus_bus *bus,
 	if (!staging)
 		return ERR_PTR(-ENOMEM);
 
-	staging->msg_seqnum = atomic64_inc_return(&bus->domain->last_id);
+	staging->msg_seqnum = atomic64_inc_return(&bus->last_message_id);
 	staging->n_parts = 0; /* we reserve n_parts, but don't enforce them */
 	staging->parts = (void *)(staging + 1);