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Date:   Tue, 18 May 2021 10:05:46 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Jiapeng Chong <jiapeng.chong@linux.alibaba.com>,
        yishaih@nvidia.com, dledford@redhat.com,
        linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] RDMA/mlx4: Remove unnessesary check in
 mlx4_ib_modify_wq()
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References: <1620382961-69701-1-git-send-email-jiapeng.chong@linux.alibaba.com>
 <20210511174302.GA1291834@nvidia.com>
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On Tue, May 11, 2021 at 02:43:02PM -0300, Jason Gunthorpe wrote:
> On Fri, May 07, 2021 at 06:22:41PM +0800, Jiapeng Chong wrote:
> > cur_state and new_state are enums and when GCC considers
> > them as unsigned, the conditions are never met.
> 
> But doesn't gcc consider enums to be 'int' as the standard requires?

Ohh, I missed that.

> 
> This change looks really sketchy to me, cur_state and new_state are
> both userspace controlled data. We should not make assumptions about
> the underlying signedness of an enum when validating user data.

I still think that the right change should be in
ib_uverbs_ex_modify_wq(), so both mlx4 and mlx5 will be protected.

Thanks

> 
> Jason