Add the __counted_by compiler attribute to the flexible array member name to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE.
Inline and use struct_size() to calculate the number of bytes to allocate for new_fn and remove the local variable len. Signed-off-by: Thorsten Blum <[email protected]> Reviewed-by: Jan Kara <[email protected]> --- fs/ext4/dir.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index ef6a3c8f3a9a..02d47a64e8d1 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -418,7 +418,7 @@ struct fname { __u32 inode; __u8 name_len; __u8 file_type; - char name[]; + char name[] __counted_by(name_len); }; /* @@ -471,14 +471,13 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, struct rb_node **p, *parent = NULL; struct fname *fname, *new_fn; struct dir_private_info *info; - int len; info = dir_file->private_data; p = &info->root.rb_node; /* Create and allocate the fname structure */ - len = sizeof(struct fname) + ent_name->len + 1; - new_fn = kzalloc(len, GFP_KERNEL); + new_fn = kzalloc(struct_size(new_fn, name, ent_name->len + 1), + GFP_KERNEL); if (!new_fn) return -ENOMEM; new_fn->hash = hash; -- 2.46.2
