If, for any reason, the open-coded arithmetic causes a wraparound,
the protection that `struct_size()` adds against potential integer
overflows is defeated. Fix this by hardening call to `struct_size()`
with `size_add()`.
Fixes: b626871a7cda ("usb: atm: Use struct_size() helper")
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/ZQSuboEIhvATAdxN@work
Signed-off-by: Kees Cook <keescook@chromium.org>
size_t size;
/* instance init */
- size = struct_size(instance, urbs, num_rcv_urbs + num_snd_urbs);
+ size = struct_size(instance, urbs,
+ size_add(num_rcv_urbs, num_snd_urbs));
instance = kzalloc(size, GFP_KERNEL);
if (!instance)
return -ENOMEM;