Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 494 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/nsalloc.c b/drivers/acpi/acpica/nsalloc.c
new file mode 100644
index 000000000..83d26abcf
--- /dev/null
+++ b/drivers/acpi/acpica/nsalloc.c
@@ -0,0 +1,494 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: nsalloc - Namespace allocation and deletion utilities
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acnamesp.h"
+
+#define _COMPONENT          ACPI_NAMESPACE
+ACPI_MODULE_NAME("nsalloc")
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_create_node
+ *
+ * PARAMETERS:  name            - Name of the new node (4 char ACPI name)
+ *
+ * RETURN:      New namespace node (Null on failure)
+ *
+ * DESCRIPTION: Create a namespace node
+ *
+ ******************************************************************************/
+struct acpi_namespace_node *acpi_ns_create_node(u32 name)
+{
+	struct acpi_namespace_node *node;
+#ifdef ACPI_DBG_TRACK_ALLOCATIONS
+	u32 temp;
+#endif
+
+	ACPI_FUNCTION_TRACE(ns_create_node);
+
+	node = acpi_os_acquire_object(acpi_gbl_namespace_cache);
+	if (!node) {
+		return_PTR(NULL);
+	}
+
+	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_allocated++);
+
+#ifdef ACPI_DBG_TRACK_ALLOCATIONS
+	temp = acpi_gbl_ns_node_list->total_allocated -
+	    acpi_gbl_ns_node_list->total_freed;
+	if (temp > acpi_gbl_ns_node_list->max_occupied) {
+		acpi_gbl_ns_node_list->max_occupied = temp;
+	}
+#endif
+
+	node->name.integer = name;
+	ACPI_SET_DESCRIPTOR_TYPE(node, ACPI_DESC_TYPE_NAMED);
+	return_PTR(node);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_delete_node
+ *
+ * PARAMETERS:  node            - Node to be deleted
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Delete a namespace node. All node deletions must come through
+ *              here. Detaches any attached objects, including any attached
+ *              data. If a handler is associated with attached data, it is
+ *              invoked before the node is deleted.
+ *
+ ******************************************************************************/
+
+void acpi_ns_delete_node(struct acpi_namespace_node *node)
+{
+	union acpi_operand_object *obj_desc;
+	union acpi_operand_object *next_desc;
+
+	ACPI_FUNCTION_NAME(ns_delete_node);
+
+	if (!node) {
+		return_VOID;
+	}
+
+	/* Detach an object if there is one */
+
+	acpi_ns_detach_object(node);
+
+	/*
+	 * Delete an attached data object list if present (objects that were
+	 * attached via acpi_attach_data). Note: After any normal object is
+	 * detached above, the only possible remaining object(s) are data
+	 * objects, in a linked list.
+	 */
+	obj_desc = node->object;
+	while (obj_desc && (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
+
+		/* Invoke the attached data deletion handler if present */
+
+		if (obj_desc->data.handler) {
+			obj_desc->data.handler(node, obj_desc->data.pointer);
+		}
+
+		next_desc = obj_desc->common.next_object;
+		acpi_ut_remove_reference(obj_desc);
+		obj_desc = next_desc;
+	}
+
+	/* Special case for the statically allocated root node */
+
+	if (node == acpi_gbl_root_node) {
+		return;
+	}
+
+	/* Now we can delete the node */
+
+	(void)acpi_os_release_object(acpi_gbl_namespace_cache, node);
+
+	ACPI_MEM_TRACKING(acpi_gbl_ns_node_list->total_freed++);
+	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Node %p, Remaining %X\n",
+			  node, acpi_gbl_current_node_count));
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_remove_node
+ *
+ * PARAMETERS:  node            - Node to be removed/deleted
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Remove (unlink) and delete a namespace node
+ *
+ ******************************************************************************/
+
+void acpi_ns_remove_node(struct acpi_namespace_node *node)
+{
+	struct acpi_namespace_node *parent_node;
+	struct acpi_namespace_node *prev_node;
+	struct acpi_namespace_node *next_node;
+
+	ACPI_FUNCTION_TRACE_PTR(ns_remove_node, node);
+
+	parent_node = node->parent;
+
+	prev_node = NULL;
+	next_node = parent_node->child;
+
+	/* Find the node that is the previous peer in the parent's child list */
+
+	while (next_node != node) {
+		prev_node = next_node;
+		next_node = next_node->peer;
+	}
+
+	if (prev_node) {
+
+		/* Node is not first child, unlink it */
+
+		prev_node->peer = node->peer;
+	} else {
+		/*
+		 * Node is first child (has no previous peer).
+		 * Link peer list to parent
+		 */
+		parent_node->child = node->peer;
+	}
+
+	/* Delete the node and any attached objects */
+
+	acpi_ns_delete_node(node);
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_install_node
+ *
+ * PARAMETERS:  walk_state      - Current state of the walk
+ *              parent_node     - The parent of the new Node
+ *              node            - The new Node to install
+ *              type            - ACPI object type of the new Node
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Initialize a new namespace node and install it amongst
+ *              its peers.
+ *
+ *              Note: Current namespace lookup is linear search. This appears
+ *              to be sufficient as namespace searches consume only a small
+ *              fraction of the execution time of the ACPI subsystem.
+ *
+ ******************************************************************************/
+
+void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namespace_node *parent_node,	/* Parent */
+			  struct acpi_namespace_node *node,	/* New Child */
+			  acpi_object_type type)
+{
+	acpi_owner_id owner_id = 0;
+	struct acpi_namespace_node *child_node;
+
+	ACPI_FUNCTION_TRACE(ns_install_node);
+
+	if (walk_state) {
+		/*
+		 * Get the owner ID from the Walk state. The owner ID is used to
+		 * track table deletion and deletion of objects created by methods.
+		 */
+		owner_id = walk_state->owner_id;
+
+		if ((walk_state->method_desc) &&
+		    (parent_node != walk_state->method_node)) {
+			/*
+			 * A method is creating a new node that is not a child of the
+			 * method (it is non-local). Mark the executing method as having
+			 * modified the namespace. This is used for cleanup when the
+			 * method exits.
+			 */
+			walk_state->method_desc->method.info_flags |=
+			    ACPI_METHOD_MODIFIED_NAMESPACE;
+		}
+	}
+
+	/* Link the new entry into the parent and existing children */
+
+	node->peer = NULL;
+	node->parent = parent_node;
+	child_node = parent_node->child;
+
+	if (!child_node) {
+		parent_node->child = node;
+	} else {
+		/* Add node to the end of the peer list */
+
+		while (child_node->peer) {
+			child_node = child_node->peer;
+		}
+
+		child_node->peer = node;
+	}
+
+	/* Init the new entry */
+
+	node->owner_id = owner_id;
+	node->type = (u8) type;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+			  "%4.4s (%s) [Node %p Owner %3.3X] added to %4.4s (%s) [Node %p]\n",
+			  acpi_ut_get_node_name(node),
+			  acpi_ut_get_type_name(node->type), node, owner_id,
+			  acpi_ut_get_node_name(parent_node),
+			  acpi_ut_get_type_name(parent_node->type),
+			  parent_node));
+
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_delete_children
+ *
+ * PARAMETERS:  parent_node     - Delete this objects children
+ *
+ * RETURN:      None.
+ *
+ * DESCRIPTION: Delete all children of the parent object. In other words,
+ *              deletes a "scope".
+ *
+ ******************************************************************************/
+
+void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
+{
+	struct acpi_namespace_node *next_node;
+	struct acpi_namespace_node *node_to_delete;
+
+	ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
+
+	if (!parent_node) {
+		return_VOID;
+	}
+
+	/* Deallocate all children at this level */
+
+	next_node = parent_node->child;
+	while (next_node) {
+
+		/* Grandchildren should have all been deleted already */
+
+		if (next_node->child) {
+			ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
+				    parent_node, next_node));
+		}
+
+		/*
+		 * Delete this child node and move on to the next child in the list.
+		 * No need to unlink the node since we are deleting the entire branch.
+		 */
+		node_to_delete = next_node;
+		next_node = next_node->peer;
+		acpi_ns_delete_node(node_to_delete);
+	}
+
+	/* Clear the parent's child pointer */
+
+	parent_node->child = NULL;
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_delete_namespace_subtree
+ *
+ * PARAMETERS:  parent_node     - Root of the subtree to be deleted
+ *
+ * RETURN:      None.
+ *
+ * DESCRIPTION: Delete a subtree of the namespace. This includes all objects
+ *              stored within the subtree.
+ *
+ ******************************************************************************/
+
+void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
+{
+	struct acpi_namespace_node *child_node = NULL;
+	u32 level = 1;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE(ns_delete_namespace_subtree);
+
+	if (!parent_node) {
+		return_VOID;
+	}
+
+	/* Lock namespace for possible update */
+
+	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+	if (ACPI_FAILURE(status)) {
+		return_VOID;
+	}
+
+	/*
+	 * Traverse the tree of objects until we bubble back up
+	 * to where we started.
+	 */
+	while (level > 0) {
+
+		/* Get the next node in this scope (NULL if none) */
+
+		child_node = acpi_ns_get_next_node(parent_node, child_node);
+		if (child_node) {
+
+			/* Found a child node - detach any attached object */
+
+			acpi_ns_detach_object(child_node);
+
+			/* Check if this node has any children */
+
+			if (child_node->child) {
+				/*
+				 * There is at least one child of this node,
+				 * visit the node
+				 */
+				level++;
+				parent_node = child_node;
+				child_node = NULL;
+			}
+		} else {
+			/*
+			 * No more children of this parent node.
+			 * Move up to the grandparent.
+			 */
+			level--;
+
+			/*
+			 * Now delete all of the children of this parent
+			 * all at the same time.
+			 */
+			acpi_ns_delete_children(parent_node);
+
+			/* New "last child" is this parent node */
+
+			child_node = parent_node;
+
+			/* Move up the tree to the grandparent */
+
+			parent_node = parent_node->parent;
+		}
+	}
+
+	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_delete_namespace_by_owner
+ *
+ * PARAMETERS:  owner_id    - All nodes with this owner will be deleted
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Delete entries within the namespace that are owned by a
+ *              specific ID. Used to delete entire ACPI tables. All
+ *              reference counts are updated.
+ *
+ * MUTEX:       Locks namespace during deletion walk.
+ *
+ ******************************************************************************/
+
+void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
+{
+	struct acpi_namespace_node *child_node;
+	struct acpi_namespace_node *deletion_node;
+	struct acpi_namespace_node *parent_node;
+	u32 level;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE_U32(ns_delete_namespace_by_owner, owner_id);
+
+	if (owner_id == 0) {
+		return_VOID;
+	}
+
+	/* Lock namespace for possible update */
+
+	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+	if (ACPI_FAILURE(status)) {
+		return_VOID;
+	}
+
+	deletion_node = NULL;
+	parent_node = acpi_gbl_root_node;
+	child_node = NULL;
+	level = 1;
+
+	/*
+	 * Traverse the tree of nodes until we bubble back up
+	 * to where we started.
+	 */
+	while (level > 0) {
+		/*
+		 * Get the next child of this parent node. When child_node is NULL,
+		 * the first child of the parent is returned
+		 */
+		child_node = acpi_ns_get_next_node(parent_node, child_node);
+
+		if (deletion_node) {
+			acpi_ns_delete_children(deletion_node);
+			acpi_ns_remove_node(deletion_node);
+			deletion_node = NULL;
+		}
+
+		if (child_node) {
+			if (child_node->owner_id == owner_id) {
+
+				/* Found a matching child node - detach any attached object */
+
+				acpi_ns_detach_object(child_node);
+			}
+
+			/* Check if this node has any children */
+
+			if (child_node->child) {
+				/*
+				 * There is at least one child of this node,
+				 * visit the node
+				 */
+				level++;
+				parent_node = child_node;
+				child_node = NULL;
+			} else if (child_node->owner_id == owner_id) {
+				deletion_node = child_node;
+			}
+		} else {
+			/*
+			 * No more children of this parent node.
+			 * Move up to the grandparent.
+			 */
+			level--;
+			if (level != 0) {
+				if (parent_node->owner_id == owner_id) {
+					deletion_node = parent_node;
+				}
+			}
+
+			/* New "last child" is this parent node */
+
+			child_node = parent_node;
+
+			/* Move up the tree to the grandparent */
+
+			parent_node = parent_node->parent;
+		}
+	}
+
+	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+	return_VOID;
+}