linux-kernel - Re: [PATCH v2] RDMA: Directly cast the sockaddr union to sockaddr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190516124428.hytvkwfltfi24lrv@verge.net.au>
Date:   Thu, 16 May 2019 14:44:28 +0200
From:   Simon Horman <horms@...ge.net.au>
To:     Jason Gunthorpe <jgg@...pe.ca>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        David Miller <davem@...emloft.net>,
        Doug Ledford <dledford@...hat.com>,
        linux-rdma <linux-rdma@...r.kernel.org>,
        Linux List Kernel Mailing <linux-kernel@...r.kernel.org>,
        Netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH v2] RDMA: Directly cast the sockaddr union to sockaddr

On Mon, May 13, 2019 at 09:55:21PM -0300, Jason Gunthorpe wrote:
> gcc 9 now does allocation size tracking and thinks that passing the member
> of a union and then accessing beyond that member's bounds is an overflow.
> 
> Instead of using the union member, use the entire union with a cast to
> get to the sockaddr. gcc will now know that the memory extends the full
> size of the union.
> 
> Signed-off-by: Jason Gunthorpe <jgg@...lanox.com>
> ---
>  drivers/infiniband/core/addr.c           | 16 ++++++++--------
>  drivers/infiniband/hw/ocrdma/ocrdma_ah.c |  5 ++---
>  drivers/infiniband/hw/ocrdma/ocrdma_hw.c |  5 ++---
>  3 files changed, 12 insertions(+), 14 deletions(-)
> 
> I missed the ocrdma files in the v1
> 
> We can revisit what to do with that repetitive union after the merge
> window, but this simple patch will eliminate the warnings for now.
> 
> Linus, I'll send this as a PR tomorrow - there is also a bug fix for
> the rdma-netlink changes posted that should go too.

<2c>
I would be very happy to see this revisited in such a way
that some use is made of the C type system (instead of casts).
</2c>