Use kmalloc_flex() when allocating a new 'struct external_name' in __d_alloc() to replace offsetof() and the open-coded size arithmetic, and to keep the size type-safe. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Link: https://patch.msgid.link/20260417094238.551114-3-thorsten.blum@linux.dev Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl> Signed-off-by: Christian Brauner <brauner@kernel.org>