Re: [PATCH v3][next] RDMA/core: Use size_{add,sub,mul}() in calls to struct_size()

[Leon Romanovsky]

On Sun, Sep 17, 2023 at 03:21:36PM -0600, Gustavo A. R. Silva wrote:
> If, for any reason, the open-coded arithmetic causes a wraparound,

The thing is that it doesn't.

> the protection that `struct_size()` provides against potential integer
> overflows is defeated. Fix this by hardening calls to `struct_size()`
> with `size_add()`, `size_sub()` and `size_mul()`.
> 
> Fixes: 467f432a521a ("RDMA/core: Split port and device counter sysfs attributes")
> Fixes: a4676388e2e2 ("RDMA/core: Simplify how the gid_attrs sysfs is created")
> Fixes: e9dd5daf884c ("IB/umad: Refactor code to use cdev_device_add()")
> Fixes: 324e227ea7c9 ("RDMA/device: Add ib_device_get_by_netdev()")
> Fixes: 5aad26a7eac5 ("IB/core: Use struct_size() in kzalloc()")
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
> ---
> Changes in v3:
>  - Include changes to other files in drivers/infiniband/core/
>  - Update changelog text with a more descriptive argument for the
>    changes.
>  - Add more `Fixes:` tags.

I don't think that any of these Fixes are necessary, as nothing wrong
in the code you changed.

Thanks