Re: [PATCH v2][next] RDMA/core: Use size_{add,mul}() in calls to struct_size()

From: Gustavo A. R. Silva
Date: Mon Sep 18 2023 - 13:57:29 EST




On 9/18/23 06:41, Leon Romanovsky wrote:
On Sun, Sep 17, 2023 at 01:59:26PM -0600, Gustavo A. R. Silva wrote:


On 9/18/23 04:49, Leon Romanovsky wrote:
On Fri, Sep 15, 2023 at 12:06:21PM -0600, Gustavo A. R. Silva wrote:


On 9/14/23 21:29, Kees Cook wrote:
On Mon, Sep 11, 2023 at 05:27:59PM -0600, Gustavo A. R. Silva wrote:
Harden calls to struct_size() with size_add() and size_mul().

Specifically, make sure that open-coded arithmetic cannot cause an
overflow/wraparound. (i.e. it will stay saturated at SIZE_MAX.)

Yep; I have another patch where I explain this in similar terms.

I'll send it, shortly.

You missed other places with similar arithmetic.
drivers/infiniband/core/device.c: pdata_rcu = kzalloc(struct_size(pdata_rcu, pdata,
drivers/infiniband/core/device.c- rdma_end_port(device) + 1),
drivers/infiniband/core/device.c- GFP_KERNEL);

drivers/infiniband/core/sa_query.c: sa_dev = kzalloc(struct_size(sa_dev, port, e - s + 1), GFP_KERNEL);
drivers/infiniband/core/user_mad.c: umad_dev = kzalloc(struct_size(umad_dev, ports, e - s + 1), GFP_KERNEL);

I haven't sent all my patches.

Please sent one patch for whole drivers/infiniband/core/ folder as your
title: "RDMA/core ..." suggests.

OK. Done:

https://lore.kernel.org/linux-hardening/ZQdt4NsJFwwOYxUR@work/

Thanks
--
Gustavo