220a5ee395
commitd7f1b4bdc7upstream. The return value calculation was incorrect: `return len - buf_size;` Initially `len = buf_size`, then `len` decreases with each operation. This results in a negative return value on success. Fix by returning `buf_size - len` which correctly calculates the actual number of bytes written. Fixes:a976d790f4("efi/cper: Add a new helper function to print bitmasks") Signed-off-by: Morduan Zang <zhangdandan@uniontech.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>