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, 499 insertions, 0 deletions

diff --git a/fs/hfsplus/attributes.c b/fs/hfsplus/attributes.c
new file mode 100644
index 000000000..7c2e589d4
--- /dev/null
+++ b/fs/hfsplus/attributes.c
@@ -0,0 +1,499 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/hfsplus/attributes.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handling of records in attributes tree
+ */
+
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+static struct kmem_cache *hfsplus_attr_tree_cachep;
+
+int __init hfsplus_create_attr_tree_cache(void)
+{
+	if (hfsplus_attr_tree_cachep)
+		return -EEXIST;
+
+	hfsplus_attr_tree_cachep =
+		kmem_cache_create("hfsplus_attr_cache",
+			sizeof(hfsplus_attr_entry), 0,
+			SLAB_HWCACHE_ALIGN, NULL);
+	if (!hfsplus_attr_tree_cachep)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void hfsplus_destroy_attr_tree_cache(void)
+{
+	kmem_cache_destroy(hfsplus_attr_tree_cachep);
+}
+
+int hfsplus_attr_bin_cmp_key(const hfsplus_btree_key *k1,
+				const hfsplus_btree_key *k2)
+{
+	__be32 k1_cnid, k2_cnid;
+
+	k1_cnid = k1->attr.cnid;
+	k2_cnid = k2->attr.cnid;
+	if (k1_cnid != k2_cnid)
+		return be32_to_cpu(k1_cnid) < be32_to_cpu(k2_cnid) ? -1 : 1;
+
+	return hfsplus_strcmp(
+			(const struct hfsplus_unistr *)&k1->attr.key_name,
+			(const struct hfsplus_unistr *)&k2->attr.key_name);
+}
+
+int hfsplus_attr_build_key(struct super_block *sb, hfsplus_btree_key *key,
+			u32 cnid, const char *name)
+{
+	int len;
+
+	memset(key, 0, sizeof(struct hfsplus_attr_key));
+	key->attr.cnid = cpu_to_be32(cnid);
+	if (name) {
+		int res = hfsplus_asc2uni(sb,
+				(struct hfsplus_unistr *)&key->attr.key_name,
+				HFSPLUS_ATTR_MAX_STRLEN, name, strlen(name),
+				HFS_XATTR_NAME);
+		if (res)
+			return res;
+		len = be16_to_cpu(key->attr.key_name.length);
+	} else {
+		key->attr.key_name.length = 0;
+		len = 0;
+	}
+
+	/* The length of the key, as stored in key_len field, does not include
+	 * the size of the key_len field itself.
+	 * So, offsetof(hfsplus_attr_key, key_name) is a trick because
+	 * it takes into consideration key_len field (__be16) of
+	 * hfsplus_attr_key structure instead of length field (__be16) of
+	 * hfsplus_attr_unistr structure.
+	 */
+	key->key_len =
+		cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) +
+				2 * len);
+
+	return 0;
+}
+
+hfsplus_attr_entry *hfsplus_alloc_attr_entry(void)
+{
+	return kmem_cache_alloc(hfsplus_attr_tree_cachep, GFP_KERNEL);
+}
+
+void hfsplus_destroy_attr_entry(hfsplus_attr_entry *entry)
+{
+	if (entry)
+		kmem_cache_free(hfsplus_attr_tree_cachep, entry);
+}
+
+#define HFSPLUS_INVALID_ATTR_RECORD -1
+
+static int hfsplus_attr_build_record(hfsplus_attr_entry *entry, int record_type,
+				u32 cnid, const void *value, size_t size)
+{
+	if (record_type == HFSPLUS_ATTR_FORK_DATA) {
+		/*
+		 * Mac OS X supports only inline data attributes.
+		 * Do nothing
+		 */
+		memset(entry, 0, sizeof(*entry));
+		return sizeof(struct hfsplus_attr_fork_data);
+	} else if (record_type == HFSPLUS_ATTR_EXTENTS) {
+		/*
+		 * Mac OS X supports only inline data attributes.
+		 * Do nothing.
+		 */
+		memset(entry, 0, sizeof(*entry));
+		return sizeof(struct hfsplus_attr_extents);
+	} else if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
+		u16 len;
+
+		memset(entry, 0, sizeof(struct hfsplus_attr_inline_data));
+		entry->inline_data.record_type = cpu_to_be32(record_type);
+		if (size <= HFSPLUS_MAX_INLINE_DATA_SIZE)
+			len = size;
+		else {
+			hfs_dbg("value size %zu is too big\n", size);
+			return HFSPLUS_INVALID_ATTR_RECORD;
+		}
+		entry->inline_data.length = cpu_to_be16(len);
+		memcpy(entry->inline_data.raw_bytes, value, len);
+		/*
+		 * Align len on two-byte boundary.
+		 * It needs to add pad byte if we have odd len.
+		 */
+		len = round_up(len, 2);
+		return offsetof(struct hfsplus_attr_inline_data, raw_bytes) +
+					len;
+	} else /* invalid input */
+		memset(entry, 0, sizeof(*entry));
+
+	return HFSPLUS_INVALID_ATTR_RECORD;
+}
+
+int hfsplus_find_attr(struct super_block *sb, u32 cnid,
+			const char *name, struct hfs_find_data *fd)
+{
+	int err = 0;
+
+	hfs_dbg("name %s, cnid %d\n", name ? name : NULL, cnid);
+
+	if (!HFSPLUS_SB(sb)->attr_tree) {
+		pr_err("attributes file doesn't exist\n");
+		return -EINVAL;
+	}
+
+	if (name) {
+		err = hfsplus_attr_build_key(sb, fd->search_key, cnid, name);
+		if (err)
+			goto failed_find_attr;
+		err = hfs_brec_find(fd, hfs_find_rec_by_key);
+		if (err == -ENOENT) {
+			/* file exists but xattr is absent */
+			err = -ENODATA;
+			goto failed_find_attr;
+		} else if (err)
+			goto failed_find_attr;
+	} else {
+		err = hfsplus_attr_build_key(sb, fd->search_key, cnid, NULL);
+		if (err)
+			goto failed_find_attr;
+		err = hfs_brec_find(fd, hfs_find_1st_rec_by_cnid);
+		if (err == -ENOENT) {
+			/* file exists but xattr is absent */
+			err = -ENODATA;
+			goto failed_find_attr;
+		} else if (err)
+			goto failed_find_attr;
+	}
+
+failed_find_attr:
+	return err;
+}
+
+int hfsplus_attr_exists(struct inode *inode, const char *name)
+{
+	int err = 0;
+	struct super_block *sb = inode->i_sb;
+	struct hfs_find_data fd;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (!HFSPLUS_SB(sb)->attr_tree)
+		return 0;
+
+	err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+	if (err)
+		return 0;
+
+	err = hfsplus_find_attr(sb, inode->i_ino, name, &fd);
+	if (err)
+		goto attr_not_found;
+
+	hfs_find_exit(&fd);
+	return 1;
+
+attr_not_found:
+	hfs_find_exit(&fd);
+	return 0;
+}
+
+static
+int hfsplus_create_attr_nolock(struct inode *inode, const char *name,
+				const void *value, size_t size,
+				struct hfs_find_data *fd,
+				hfsplus_attr_entry *entry_ptr)
+{
+	struct super_block *sb = inode->i_sb;
+	int entry_size;
+	int err;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (name) {
+		err = hfsplus_attr_build_key(sb, fd->search_key,
+						inode->i_ino, name);
+		if (err)
+			return err;
+	} else
+		return -EINVAL;
+
+	/* Mac OS X supports only inline data attributes. */
+	entry_size = hfsplus_attr_build_record(entry_ptr,
+					HFSPLUS_ATTR_INLINE_DATA,
+					inode->i_ino,
+					value, size);
+	if (entry_size == HFSPLUS_INVALID_ATTR_RECORD) {
+		if (size > HFSPLUS_MAX_INLINE_DATA_SIZE)
+			err = -E2BIG;
+		else
+			err = -EINVAL;
+		hfs_dbg("unable to store value: err %d\n", err);
+		return err;
+	}
+
+	err = hfs_brec_find(fd, hfs_find_rec_by_key);
+	if (err != -ENOENT) {
+		if (!err)
+			err = -EEXIST;
+		return err;
+	}
+
+	err = hfs_brec_insert(fd, entry_ptr, entry_size);
+	if (err) {
+		hfs_dbg("unable to store value: err %d\n", err);
+		return err;
+	}
+
+	hfsplus_mark_inode_dirty(HFSPLUS_ATTR_TREE_I(sb), HFSPLUS_I_ATTR_DIRTY);
+	hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY);
+
+	return 0;
+}
+
+int hfsplus_create_attr(struct inode *inode,
+			const char *name,
+			const void *value, size_t size)
+{
+	struct super_block *sb = inode->i_sb;
+	struct hfs_find_data fd;
+	hfsplus_attr_entry *entry_ptr;
+	int err;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (!HFSPLUS_SB(sb)->attr_tree) {
+		pr_err("attributes file doesn't exist\n");
+		return -EINVAL;
+	}
+
+	entry_ptr = hfsplus_alloc_attr_entry();
+	if (!entry_ptr)
+		return -ENOMEM;
+
+	err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+	if (err)
+		goto failed_init_create_attr;
+
+	/* Fail early and avoid ENOSPC during the btree operation */
+	err = hfs_bmap_reserve(fd.tree, fd.tree->depth + 1);
+	if (err)
+		goto failed_create_attr;
+
+	err = hfsplus_create_attr_nolock(inode, name, value, size,
+					 &fd, entry_ptr);
+	if (err)
+		goto failed_create_attr;
+
+failed_create_attr:
+	hfs_find_exit(&fd);
+
+failed_init_create_attr:
+	hfsplus_destroy_attr_entry(entry_ptr);
+	return err;
+}
+
+static int __hfsplus_delete_attr(struct inode *inode, u32 cnid,
+					struct hfs_find_data *fd)
+{
+	int err;
+	__be32 found_cnid, record_type;
+
+	found_cnid = U32_MAX;
+	hfs_bnode_read(fd->bnode, &found_cnid,
+			fd->keyoffset +
+			offsetof(struct hfsplus_attr_key, cnid),
+			sizeof(__be32));
+	if (cnid != be32_to_cpu(found_cnid))
+		return -ENODATA;
+
+	hfs_bnode_read(fd->bnode, &record_type,
+			fd->entryoffset, sizeof(record_type));
+
+	switch (be32_to_cpu(record_type)) {
+	case HFSPLUS_ATTR_INLINE_DATA:
+		/* All is OK. Do nothing. */
+		break;
+	case HFSPLUS_ATTR_FORK_DATA:
+	case HFSPLUS_ATTR_EXTENTS:
+		pr_err("only inline data xattr are supported\n");
+		return -EOPNOTSUPP;
+	default:
+		pr_err("invalid extended attribute record\n");
+		return -ENOENT;
+	}
+
+	/* Avoid btree corruption */
+	hfs_bnode_read(fd->bnode, fd->search_key,
+			fd->keyoffset, fd->keylength);
+
+	err = hfs_brec_remove(fd);
+	if (err)
+		return err;
+
+	hfsplus_mark_inode_dirty(HFSPLUS_ATTR_TREE_I(inode->i_sb),
+				 HFSPLUS_I_ATTR_DIRTY);
+	hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY);
+	return 0;
+}
+
+static
+int hfsplus_delete_attr_nolock(struct inode *inode, const char *name,
+				struct hfs_find_data *fd)
+{
+	struct super_block *sb = inode->i_sb;
+	int err;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (name) {
+		err = hfsplus_attr_build_key(sb, fd->search_key,
+						inode->i_ino, name);
+		if (err)
+			return err;
+	} else {
+		pr_err("invalid extended attribute name\n");
+		return -EINVAL;
+	}
+
+	err = hfs_brec_find(fd, hfs_find_rec_by_key);
+	if (err == -ENOENT) {
+		/* file exists but xattr is absent */
+		return -ENODATA;
+	} else if (err)
+		return err;
+
+	err = __hfsplus_delete_attr(inode, inode->i_ino, fd);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+int hfsplus_delete_attr(struct inode *inode, const char *name)
+{
+	int err = 0;
+	struct super_block *sb = inode->i_sb;
+	struct hfs_find_data fd;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (!HFSPLUS_SB(sb)->attr_tree) {
+		pr_err("attributes file doesn't exist\n");
+		return -EINVAL;
+	}
+
+	err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+	if (err)
+		return err;
+
+	/* Fail early and avoid ENOSPC during the btree operation */
+	err = hfs_bmap_reserve(fd.tree, fd.tree->depth);
+	if (err)
+		goto out;
+
+	err = hfsplus_delete_attr_nolock(inode, name, &fd);
+	if (err)
+		goto out;
+
+out:
+	hfs_find_exit(&fd);
+	return err;
+}
+
+int hfsplus_delete_all_attrs(struct inode *dir, u32 cnid)
+{
+	int err = 0;
+	struct hfs_find_data fd;
+
+	hfs_dbg("cnid %d\n", cnid);
+
+	if (!HFSPLUS_SB(dir->i_sb)->attr_tree) {
+		pr_err("attributes file doesn't exist\n");
+		return -EINVAL;
+	}
+
+	err = hfs_find_init(HFSPLUS_SB(dir->i_sb)->attr_tree, &fd);
+	if (err)
+		return err;
+
+	for (;;) {
+		err = hfsplus_find_attr(dir->i_sb, cnid, NULL, &fd);
+		if (err == -ENOENT || err == -ENODATA) {
+			/*
+			 * xattr has not been found
+			 */
+			err = -ENODATA;
+			goto end_delete_all;
+		} else if (err) {
+			pr_err("xattr search failed\n");
+			goto end_delete_all;
+		}
+
+		err = __hfsplus_delete_attr(dir, cnid, &fd);
+		if (err)
+			goto end_delete_all;
+	}
+
+end_delete_all:
+	hfs_find_exit(&fd);
+	return err;
+}
+
+int hfsplus_replace_attr(struct inode *inode,
+			 const char *name,
+			 const void *value, size_t size)
+{
+	struct super_block *sb = inode->i_sb;
+	struct hfs_find_data fd;
+	hfsplus_attr_entry *entry_ptr;
+	int err = 0;
+
+	hfs_dbg("name %s, ino %llu\n",
+		name ? name : NULL, inode->i_ino);
+
+	if (!HFSPLUS_SB(sb)->attr_tree) {
+		pr_err("attributes file doesn't exist\n");
+		return -EINVAL;
+	}
+
+	entry_ptr = hfsplus_alloc_attr_entry();
+	if (!entry_ptr)
+		return -ENOMEM;
+
+	err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd);
+	if (err)
+		goto failed_init_replace_attr;
+
+	/* Fail early and avoid ENOSPC during the btree operation */
+	err = hfs_bmap_reserve(fd.tree, fd.tree->depth + 1);
+	if (err)
+		goto failed_replace_attr;
+
+	err = hfsplus_delete_attr_nolock(inode, name, &fd);
+	if (err)
+		goto failed_replace_attr;
+
+	err = hfsplus_create_attr_nolock(inode, name, value, size,
+					 &fd, entry_ptr);
+	if (err)
+		goto failed_replace_attr;
+
+failed_replace_attr:
+	hfs_find_exit(&fd);
+
+failed_init_replace_attr:
+	hfsplus_destroy_attr_entry(entry_ptr);
+	return err;
+}