Commit 26a836ce authored by Su Yue's avatar Su Yue Committed by David Sterba
Browse files

btrfs: Check name_len on add_inode_ref call path 



replay_one_buffer first reads buffers and dispatches items accroding to
the item type.
In this patch, add_inode_ref handles inode_ref and inode_extref.
Then add_inode_ref calls ref_get_fields and extref_get_fields to read
ref/extref name for the first time.
So checking name_len before reading those two is fine.

add_inode_ref also calls inode_in_dir to match ref/extref in parent_dir.
The call graph includes btrfs_match_dir_item_name to read dir_item name
in the parent dir.
Checking first dir_item is not enough. Change it to verify every
dir_item while doing matches.

Signed-off-by: default avatarSu Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent e79a3327

fs/btrfs/dir-item.c

+2 −2
Original line number Diff line number Diff line
@@ -395,8 +395,6 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info, 


	leaf = path->nodes[0];

	dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);

	if (verify_dir_item(fs_info, leaf, path->slots[0], dir_item))

		return NULL;



	total_len = btrfs_item_size_nr(leaf, path->slots[0]);

	while (cur < total_len) {
@@ -405,6 +403,8 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info, 
			btrfs_dir_data_len(leaf, dir_item);

		name_ptr = (unsigned long)(dir_item + 1);



		if (verify_dir_item(fs_info, leaf, path->slots[0], dir_item))

			return NULL;

		if (btrfs_dir_name_len(leaf, dir_item) == name_len &&

		    memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)

			return dir_item;

fs/btrfs/tree-log.c

+18 −9
Original line number Diff line number Diff line
@@ -1175,15 +1175,19 @@ next: 
	return 0;

}



static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,

			     u32 *namelen, char **name, u64 *index,

			     u64 *parent_objectid)

static int extref_get_fields(struct extent_buffer *eb, int slot,

			     unsigned long ref_ptr, u32 *namelen, char **name,

			     u64 *index, u64 *parent_objectid)

{

	struct btrfs_inode_extref *extref;



	extref = (struct btrfs_inode_extref *)ref_ptr;



	*namelen = btrfs_inode_extref_name_len(eb, extref);

	if (!btrfs_is_name_len_valid(eb, slot, (unsigned long)&extref->name,

				     *namelen))

		return -EIO;



	*name = kmalloc(*namelen, GFP_NOFS);

	if (*name == NULL)

		return -ENOMEM;
@@ -1198,14 +1202,19 @@ static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr, 
	return 0;

}



static int ref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,

			  u32 *namelen, char **name, u64 *index)

static int ref_get_fields(struct extent_buffer *eb, int slot,

			  unsigned long ref_ptr, u32 *namelen, char **name,

			  u64 *index)

{

	struct btrfs_inode_ref *ref;



	ref = (struct btrfs_inode_ref *)ref_ptr;



	*namelen = btrfs_inode_ref_name_len(eb, ref);

	if (!btrfs_is_name_len_valid(eb, slot, (unsigned long)(ref + 1),

				     *namelen))

		return -EIO;



	*name = kmalloc(*namelen, GFP_NOFS);

	if (*name == NULL)

		return -ENOMEM;
@@ -1280,8 +1289,8 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans, 


	while (ref_ptr < ref_end) {

		if (log_ref_ver) {

			ret = extref_get_fields(eb, ref_ptr, &namelen, &name,

						&ref_index, &parent_objectid);

			ret = extref_get_fields(eb, slot, ref_ptr, &namelen,

					  &name, &ref_index, &parent_objectid);

			/*

			 * parent object can change from one array

			 * item to another.
@@ -1293,8 +1302,8 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans, 
				goto out;

			}

		} else {

			ret = ref_get_fields(eb, ref_ptr, &namelen, &name,

					     &ref_index);

			ret = ref_get_fields(eb, slot, ref_ptr, &namelen,

					     &name, &ref_index);

		}

		if (ret)

			goto out;

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