We use this helper for inode-resolve and path resolution in send, so update this helper to properly decrypt any encrypted names it finds. Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> --- fs/btrfs/backref.c | 45 +++++++++++++++++++++++++++++++++++++++++---- fs/btrfs/fscrypt.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/fscrypt.h | 11 +++++++++++ 3 files changed, 98 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index f58fe7c745c2..9ed854b9f3fc 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -20,6 +20,7 @@ #include "extent-tree.h" #include "relocation.h" #include "tree-checker.h" +#include "fscrypt.h" /* Just arbitrary numbers so we can be sure one of these happened. */ #define BACKREF_FOUND_SHARED 6 @@ -2117,6 +2118,42 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid, return ret; } +static int copy_resolved_iref_to_buf(struct btrfs_root *fs_root, + struct extent_buffer *eb, + char *dest, u64 parent, + unsigned long name_off, u32 name_len, + s64 *bytes_left) +{ + struct btrfs_fs_info *fs_info = fs_root->fs_info; + struct fscrypt_str fname = FSTR_INIT(NULL, 0); + int ret; + + /* No encryption, just copy the name in. */ + if (!btrfs_fs_incompat(fs_info, ENCRYPT)) { + *bytes_left -= name_len; + if (*bytes_left >= 0) + read_extent_buffer(eb, dest + *bytes_left, + name_off, name_len); + return 0; + } + + ret = fscrypt_fname_alloc_buffer(BTRFS_NAME_LEN, &fname); + if (ret) + return ret; + + ret = btrfs_decrypt_name(fs_root, eb, name_off, name_len, parent, + &fname); + if (ret) + goto out; + + *bytes_left -= fname.len; + if (*bytes_left >= 0) + memcpy(dest + *bytes_left, fname.name, fname.len); +out: + fscrypt_fname_free_buffer(&fname); + return ret; +} + /* * this iterates to turn a name (from iref/extref) into a full filesystem path. * Elements of the path are separated by '/' and the path is guaranteed to be @@ -2148,10 +2185,10 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, dest[bytes_left] = '\0'; while (1) { - bytes_left -= name_len; - if (bytes_left >= 0) - read_extent_buffer(eb, dest + bytes_left, - name_off, name_len); + ret = copy_resolved_iref_to_buf(fs_root, eb, dest, parent, + name_off, name_len, &bytes_left); + if (ret) + break; if (eb != eb_in) { if (!path->skip_locking) btrfs_tree_read_unlock(eb); diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c index 2fbceec62dc7..6211fa17bf79 100644 --- a/fs/btrfs/fscrypt.c +++ b/fs/btrfs/fscrypt.c @@ -355,6 +355,52 @@ int btrfs_fscrypt_bio_length(struct bio *bio, u64 map_length) return map_length; } +int btrfs_decrypt_name(struct btrfs_root *root, struct extent_buffer *eb, + unsigned long name_off, u32 name_len, + u64 parent_ino, struct fscrypt_str *name) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + struct inode *dir; + struct fscrypt_str iname = FSTR_INIT(NULL, 0); + int ret; + + ASSERT(name_len <= BTRFS_NAME_LEN); + + ret = fscrypt_fname_alloc_buffer(name_len, &iname); + if (ret) + return ret; + + dir = btrfs_iget(fs_info->sb, parent_ino, root); + if (IS_ERR(dir)) { + ret = PTR_ERR(dir); + goto out; + } + + /* + * Directory isn't encrypted, the name isn't encrypted, we can just copy + * it into the buffer. + */ + if (!IS_ENCRYPTED(dir)) { + read_extent_buffer(eb, name->name, name_off, name_len); + name->len = name_len; + goto out_inode; + } + + read_extent_buffer(eb, iname.name, name_off, name_len); + + ret = fscrypt_prepare_readdir(dir); + if (ret) + goto out_inode; + + ASSERT(dir->i_crypt_info); + ret = fscrypt_fname_disk_to_usr(dir, 0, 0, &iname, name); +out_inode: + iput(dir); +out: + fscrypt_fname_free_buffer(&iname); + return ret; +} + const struct fscrypt_operations btrfs_fscrypt_ops = { .has_per_extent_encryption = 1, .get_context = btrfs_fscrypt_get_context, diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h index c4a327be0eeb..aba01bacc165 100644 --- a/fs/btrfs/fscrypt.h +++ b/fs/btrfs/fscrypt.h @@ -36,6 +36,9 @@ bool btrfs_mergeable_encrypted_bio(struct bio *bio, struct inode *inode, struct fscrypt_extent_info *fi, u64 logical_offset); int btrfs_fscrypt_bio_length(struct bio *bio, u64 map_length); +int btrfs_decrypt_name(struct btrfs_root *root, struct extent_buffer *eb, + unsigned long name_off, u32 name_len, + u64 parent_ino, struct fscrypt_str *name); #else static inline int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode, @@ -94,6 +97,14 @@ static inline u64 btrfs_fscrypt_bio_length(struct bio *bio, u64 map_length) { return map_length; } + +static inline int btrfs_decrypt_name(struct btrfs_root *root, + struct extent_buffer *eb, + unsigned long name_off, u32 name_len, + u64 parent_ino, struct fscrypt_str *name) +{ + return -EINVAL; +} #endif /* CONFIG_FS_ENCRYPTION */ extern const struct fscrypt_operations btrfs_fscrypt_ops; -- 2.41.0