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, 563 insertions, 0 deletions

diff --git a/fs/hfsplus/brec.c b/fs/hfsplus/brec.c
new file mode 100644
index 000000000..f416e562d
--- /dev/null
+++ b/fs/hfsplus/brec.c
@@ -0,0 +1,563 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hfsplus/brec.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Handle individual btree records
+ */
+
+#include <linux/limits.h>
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd);
+static int hfs_brec_update_parent(struct hfs_find_data *fd);
+static int hfs_btree_inc_height(struct hfs_btree *);
+
+/* Get the length and offset of the given record in the given node */
+u16 hfs_brec_lenoff(struct hfs_bnode *node, u16 rec, u16 *off)
+{
+	__be16 retval[2];
+	u16 data_off;
+	u16 next_off;
+
+	if (hfs_brec_record_invalid(node, rec)) {
+		*off = U16_MAX;
+		return U16_MAX;
+	}
+
+	data_off = node->tree->node_size - (rec + 2) * 2;
+	hfs_bnode_read(node, retval, data_off, 4);
+	*off = be16_to_cpu(retval[1]);
+	next_off = be16_to_cpu(retval[0]);
+	if (hfs_brec_offsets_invalid(node, *off, next_off)) {
+		*off = U16_MAX;
+		return U16_MAX;
+	}
+	return next_off - *off;
+}
+
+/* Get the length of the key from a keyed record */
+u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
+{
+	u16 retval, recoff, len;
+
+	if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
+		return 0;
+	if (hfs_brec_record_invalid(node, rec))
+		return U16_MAX;
+
+	if ((node->type == HFS_NODE_INDEX) &&
+	   !(node->tree->attributes & HFS_TREE_VARIDXKEYS) &&
+	   (node->tree->cnid != HFSPLUS_ATTR_CNID)) {
+		retval = node->tree->max_key_len + 2;
+	} else {
+		len = hfs_brec_lenoff(node, rec, &recoff);
+		if (hfs_brec_len_invalid(node, len))
+			return len;
+
+		retval = hfs_bnode_read_u16(node, recoff) + 2;
+		if (retval > node->tree->max_key_len + 2) {
+			pr_err("keylen %d too large\n",
+				retval);
+			retval = U16_MAX;
+		}
+	}
+	return retval;
+}
+
+int hfs_brec_insert(struct hfs_find_data *fd, void *entry, u32 entry_len)
+{
+	struct hfs_btree *tree;
+	struct hfs_bnode *node, *new_node;
+	int size, key_len, rec;
+	int data_off, end_off;
+	int idx_rec_off, data_rec_off, end_rec_off;
+	__be32 cnid;
+
+	tree = fd->tree;
+	if (!fd->bnode) {
+		if (!tree->root)
+			hfs_btree_inc_height(tree);
+		node = hfs_bnode_find(tree, tree->leaf_head);
+		if (IS_ERR(node))
+			return PTR_ERR(node);
+		fd->bnode = node;
+		fd->record = -1;
+	}
+	new_node = NULL;
+	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
+again:
+	/* new record idx and complete record size */
+	rec = fd->record + 1;
+	size = key_len + entry_len;
+
+	node = fd->bnode;
+	hfs_bnode_dump(node);
+	/* get last offset */
+	end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
+	end_off = hfs_bnode_read_u16(node, end_rec_off);
+	end_rec_off -= 2;
+	hfs_dbg("rec %d, size %d, end_off %d, end_rec_off %d\n",
+		rec, size, end_off, end_rec_off);
+	if (size > end_rec_off - end_off) {
+		if (new_node)
+			panic("not enough room!\n");
+		new_node = hfs_bnode_split(fd);
+		if (IS_ERR(new_node))
+			return PTR_ERR(new_node);
+		goto again;
+	}
+	if (node->type == HFS_NODE_LEAF) {
+		tree->leaf_count++;
+		mark_inode_dirty(tree->inode);
+	}
+	node->num_recs++;
+	/* write new last offset */
+	hfs_bnode_write_u16(node,
+		offsetof(struct hfs_bnode_desc, num_recs),
+		node->num_recs);
+	hfs_bnode_write_u16(node, end_rec_off, end_off + size);
+	data_off = end_off;
+	data_rec_off = end_rec_off + 2;
+	idx_rec_off = tree->node_size - (rec + 1) * 2;
+	if (idx_rec_off == data_rec_off)
+		goto skip;
+	/* move all following entries */
+	do {
+		data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
+		hfs_bnode_write_u16(node, data_rec_off, data_off + size);
+		data_rec_off += 2;
+	} while (data_rec_off < idx_rec_off);
+
+	/* move data away */
+	hfs_bnode_move(node, data_off + size, data_off,
+		       end_off - data_off);
+
+skip:
+	hfs_bnode_write(node, fd->search_key, data_off, key_len);
+	hfs_bnode_write(node, entry, data_off + key_len, entry_len);
+	hfs_bnode_dump(node);
+
+	/*
+	 * update parent key if we inserted a key
+	 * at the start of the node and it is not the new node
+	 */
+	if (!rec && new_node != node) {
+		hfs_bnode_read_key(node, fd->search_key, data_off + size);
+		hfs_brec_update_parent(fd);
+	}
+
+	if (new_node) {
+		hfs_bnode_put(fd->bnode);
+		if (!new_node->parent) {
+			hfs_btree_inc_height(tree);
+			new_node->parent = tree->root;
+		}
+		fd->bnode = hfs_bnode_find(tree, new_node->parent);
+
+		/* create index data entry */
+		cnid = cpu_to_be32(new_node->this);
+		entry = &cnid;
+		entry_len = sizeof(cnid);
+
+		/* get index key */
+		hfs_bnode_read_key(new_node, fd->search_key, 14);
+		__hfs_brec_find(fd->bnode, fd, hfs_find_rec_by_key);
+
+		hfs_bnode_put(new_node);
+		new_node = NULL;
+
+		if ((tree->attributes & HFS_TREE_VARIDXKEYS) ||
+				(tree->cnid == HFSPLUS_ATTR_CNID))
+			key_len = be16_to_cpu(fd->search_key->key_len) + 2;
+		else {
+			fd->search_key->key_len =
+				cpu_to_be16(tree->max_key_len);
+			key_len = tree->max_key_len + 2;
+		}
+		goto again;
+	}
+
+	return 0;
+}
+
+int hfs_brec_remove(struct hfs_find_data *fd)
+{
+	struct hfs_btree *tree;
+	struct hfs_bnode *node, *parent;
+	int end_off, rec_off, data_off, size;
+	int res;
+
+	tree = fd->tree;
+	node = fd->bnode;
+again:
+	if (hfs_brec_record_invalid(node, fd->record))
+		return -EINVAL;
+
+	rec_off = tree->node_size - (fd->record + 2) * 2;
+	end_off = tree->node_size - (node->num_recs + 1) * 2;
+
+	if (node->type == HFS_NODE_LEAF) {
+		if (tree->leaf_count == 0)
+			return -EINVAL;
+		tree->leaf_count--;
+		mark_inode_dirty(tree->inode);
+	}
+	hfs_bnode_dump(node);
+	hfs_dbg("rec %d, len %d\n",
+		fd->record, fd->keylength + fd->entrylength);
+	if (!--node->num_recs) {
+		hfs_bnode_unlink(node);
+		if (!node->parent)
+			return 0;
+		parent = hfs_bnode_find(tree, node->parent);
+		if (IS_ERR(parent))
+			return PTR_ERR(parent);
+		hfs_bnode_put(node);
+		node = fd->bnode = parent;
+
+		res = __hfs_brec_find(node, fd, hfs_find_rec_by_key);
+		if (res && res != -ENOENT)
+			return res;
+		goto again;
+	}
+	hfs_bnode_write_u16(node,
+		offsetof(struct hfs_bnode_desc, num_recs),
+		node->num_recs);
+
+	if (rec_off == end_off)
+		goto skip;
+	size = fd->keylength + fd->entrylength;
+
+	do {
+		data_off = hfs_bnode_read_u16(node, rec_off);
+		hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
+		rec_off -= 2;
+	} while (rec_off >= end_off);
+
+	/* fill hole */
+	hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
+		       data_off - fd->keyoffset - size);
+skip:
+	hfs_bnode_dump(node);
+	if (!fd->record)
+		hfs_brec_update_parent(fd);
+	return 0;
+}
+
+static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd)
+{
+	struct hfs_btree *tree;
+	struct hfs_bnode *node, *new_node, *next_node;
+	struct hfs_bnode_desc node_desc;
+	int num_recs, new_rec_off, new_off, old_rec_off;
+	int data_start, data_end, size;
+	size_t rec_off_tbl_size;
+	size_t node_desc_size = sizeof(struct hfs_bnode_desc);
+	size_t rec_size = sizeof(__be16);
+
+	tree = fd->tree;
+	node = fd->bnode;
+	new_node = hfs_bmap_alloc(tree);
+	if (IS_ERR(new_node))
+		return new_node;
+	hfs_bnode_get(node);
+	hfs_dbg("this %d - new %d - next %d\n",
+		node->this, new_node->this, node->next);
+	new_node->next = node->next;
+	new_node->prev = node->this;
+	new_node->parent = node->parent;
+	new_node->type = node->type;
+	new_node->height = node->height;
+
+	if (node->next)
+		next_node = hfs_bnode_find(tree, node->next);
+	else
+		next_node = NULL;
+
+	if (IS_ERR(next_node)) {
+		hfs_bnode_put(node);
+		hfs_bnode_put(new_node);
+		return next_node;
+	}
+
+	rec_off_tbl_size = node->num_recs * rec_size;
+	size = tree->node_size / 2;
+	size -= node_desc_size;
+	size -= rec_off_tbl_size;
+	old_rec_off = tree->node_size - (2 * rec_size);
+
+	num_recs = 1;
+	for (;;) {
+		data_start = hfs_bnode_read_u16(node, old_rec_off);
+		if (data_start > size)
+			break;
+		old_rec_off -= rec_size;
+		if (++num_recs < node->num_recs)
+			continue;
+		hfs_bnode_put(node);
+		hfs_bnode_unlink(new_node);
+		hfs_bnode_put(new_node);
+		if (next_node)
+			hfs_bnode_put(next_node);
+		return ERR_PTR(-ENOSPC);
+	}
+
+	if (fd->record + 1 < num_recs) {
+		/* new record is in the lower half,
+		 * so leave some more space there
+		 */
+		old_rec_off += rec_size;
+		num_recs--;
+		data_start = hfs_bnode_read_u16(node, old_rec_off);
+	} else {
+		hfs_bnode_put(node);
+		hfs_bnode_get(new_node);
+		fd->bnode = new_node;
+		fd->record -= num_recs;
+		fd->keyoffset -= data_start - node_desc_size;
+		fd->entryoffset -= data_start - node_desc_size;
+	}
+	new_node->num_recs = node->num_recs - num_recs;
+	node->num_recs = num_recs;
+
+	new_rec_off = tree->node_size - rec_size;
+	new_off = node_desc_size;
+	size = data_start - new_off;
+	num_recs = new_node->num_recs;
+	data_end = data_start;
+	while (num_recs) {
+		hfs_bnode_write_u16(new_node, new_rec_off, new_off);
+		old_rec_off -= rec_size;
+		new_rec_off -= rec_size;
+		data_end = hfs_bnode_read_u16(node, old_rec_off);
+		new_off = data_end - size;
+		num_recs--;
+	}
+	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
+	hfs_bnode_copy(new_node, node_desc_size,
+			node, data_start, data_end - data_start);
+
+	/* update new bnode header */
+	node_desc.next = cpu_to_be32(new_node->next);
+	node_desc.prev = cpu_to_be32(new_node->prev);
+	node_desc.type = new_node->type;
+	node_desc.height = new_node->height;
+	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
+	node_desc.reserved = 0;
+	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
+
+	/* update previous bnode header */
+	node->next = new_node->this;
+	hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
+	node_desc.next = cpu_to_be32(node->next);
+	node_desc.num_recs = cpu_to_be16(node->num_recs);
+	hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
+
+	/* update next bnode header */
+	if (next_node) {
+		next_node->prev = new_node->this;
+		hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
+		node_desc.prev = cpu_to_be32(next_node->prev);
+		hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
+		hfs_bnode_put(next_node);
+	} else if (node->this == tree->leaf_tail) {
+		/* if there is no next node, this might be the new tail */
+		tree->leaf_tail = new_node->this;
+		mark_inode_dirty(tree->inode);
+	}
+
+	hfs_bnode_dump(node);
+	hfs_bnode_dump(new_node);
+	hfs_bnode_put(node);
+
+	return new_node;
+}
+
+static int hfs_brec_update_parent(struct hfs_find_data *fd)
+{
+	struct hfs_btree *tree;
+	struct hfs_bnode *node, *new_node, *parent;
+	int newkeylen, diff;
+	int rec, rec_off, end_rec_off;
+	int start_off, end_off;
+	int res;
+
+	tree = fd->tree;
+	node = fd->bnode;
+	new_node = NULL;
+	if (!node->parent)
+		return 0;
+
+again:
+	parent = hfs_bnode_find(tree, node->parent);
+	if (IS_ERR(parent))
+		return PTR_ERR(parent);
+	res = __hfs_brec_find(parent, fd, hfs_find_rec_by_key);
+	if (res && res != -ENOENT)
+		return res;
+	if (fd->record < 0)
+		return -ENOENT;
+	hfs_bnode_dump(parent);
+	rec = fd->record;
+
+	/* size difference between old and new key */
+	if ((tree->attributes & HFS_TREE_VARIDXKEYS) ||
+				(tree->cnid == HFSPLUS_ATTR_CNID))
+		newkeylen = hfs_bnode_read_u16(node, 14) + 2;
+	else
+		fd->keylength = newkeylen = tree->max_key_len + 2;
+	hfs_dbg("rec %d, keylength %d, newkeylen %d\n",
+		rec, fd->keylength, newkeylen);
+
+	rec_off = tree->node_size - (rec + 2) * 2;
+	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
+	diff = newkeylen - fd->keylength;
+	if (!diff)
+		goto skip;
+	if (diff > 0) {
+		end_off = hfs_bnode_read_u16(parent, end_rec_off);
+		if (end_rec_off - end_off < diff) {
+
+			hfs_dbg("splitting index node\n");
+			fd->bnode = parent;
+			new_node = hfs_bnode_split(fd);
+			if (IS_ERR(new_node))
+				return PTR_ERR(new_node);
+			parent = fd->bnode;
+			rec = fd->record;
+			rec_off = tree->node_size - (rec + 2) * 2;
+			end_rec_off = tree->node_size -
+				(parent->num_recs + 1) * 2;
+		}
+	}
+
+	end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
+	hfs_bnode_write_u16(parent, rec_off, start_off + diff);
+	start_off -= 4;	/* move previous cnid too */
+
+	while (rec_off > end_rec_off) {
+		rec_off -= 2;
+		end_off = hfs_bnode_read_u16(parent, rec_off);
+		hfs_bnode_write_u16(parent, rec_off, end_off + diff);
+	}
+	hfs_bnode_move(parent, start_off + diff, start_off,
+		       end_off - start_off);
+skip:
+	hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
+	hfs_bnode_dump(parent);
+
+	hfs_bnode_put(node);
+	node = parent;
+
+	if (new_node) {
+		__be32 cnid;
+
+		if (!new_node->parent) {
+			hfs_btree_inc_height(tree);
+			new_node->parent = tree->root;
+		}
+		fd->bnode = hfs_bnode_find(tree, new_node->parent);
+		/* create index key and entry */
+		hfs_bnode_read_key(new_node, fd->search_key, 14);
+		cnid = cpu_to_be32(new_node->this);
+
+		__hfs_brec_find(fd->bnode, fd, hfs_find_rec_by_key);
+		hfs_brec_insert(fd, &cnid, sizeof(cnid));
+		hfs_bnode_put(fd->bnode);
+		hfs_bnode_put(new_node);
+
+		if (!rec) {
+			if (new_node == node)
+				goto out;
+			/* restore search_key */
+			hfs_bnode_read_key(node, fd->search_key, 14);
+		}
+		new_node = NULL;
+	}
+
+	if (!rec && node->parent)
+		goto again;
+out:
+	fd->bnode = node;
+	return 0;
+}
+
+static int hfs_btree_inc_height(struct hfs_btree *tree)
+{
+	struct hfs_bnode *node, *new_node;
+	struct hfs_bnode_desc node_desc;
+	int key_size, rec;
+	__be32 cnid;
+
+	node = NULL;
+	if (tree->root) {
+		node = hfs_bnode_find(tree, tree->root);
+		if (IS_ERR(node))
+			return PTR_ERR(node);
+	}
+	new_node = hfs_bmap_alloc(tree);
+	if (IS_ERR(new_node)) {
+		hfs_bnode_put(node);
+		return PTR_ERR(new_node);
+	}
+
+	tree->root = new_node->this;
+	if (!tree->depth) {
+		tree->leaf_head = tree->leaf_tail = new_node->this;
+		new_node->type = HFS_NODE_LEAF;
+		new_node->num_recs = 0;
+	} else {
+		new_node->type = HFS_NODE_INDEX;
+		new_node->num_recs = 1;
+	}
+	new_node->parent = 0;
+	new_node->next = 0;
+	new_node->prev = 0;
+	new_node->height = ++tree->depth;
+
+	node_desc.next = cpu_to_be32(new_node->next);
+	node_desc.prev = cpu_to_be32(new_node->prev);
+	node_desc.type = new_node->type;
+	node_desc.height = new_node->height;
+	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
+	node_desc.reserved = 0;
+	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
+
+	rec = tree->node_size - 2;
+	hfs_bnode_write_u16(new_node, rec, 14);
+
+	if (node) {
+		/* insert old root idx into new root */
+		node->parent = tree->root;
+		if (node->type == HFS_NODE_LEAF ||
+				tree->attributes & HFS_TREE_VARIDXKEYS ||
+				tree->cnid == HFSPLUS_ATTR_CNID)
+			key_size = hfs_bnode_read_u16(node, 14) + 2;
+		else
+			key_size = tree->max_key_len + 2;
+		hfs_bnode_copy(new_node, 14, node, 14, key_size);
+
+		if (!(tree->attributes & HFS_TREE_VARIDXKEYS) &&
+				(tree->cnid != HFSPLUS_ATTR_CNID)) {
+			key_size = tree->max_key_len + 2;
+			hfs_bnode_write_u16(new_node, 14, tree->max_key_len);
+		}
+		cnid = cpu_to_be32(node->this);
+		hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
+
+		rec -= 2;
+		hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
+
+		hfs_bnode_put(node);
+	}
+	hfs_bnode_put(new_node);
+	mark_inode_dirty(tree->inode);
+
+	return 0;
+}