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Date:   Sun, 4 Apr 2021 13:33:43 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     Doug Ledford <dledford@redhat.com>, Jason Gunthorpe <jgg@ziepe.ca>,
        Mark Bloch <markb@mellanox.com>, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] RDMA/addr: potential uninitialized variable in
 ib_nl_process_good_ip_rsep()
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References: <YGcES6MsXGnh83qi@mwanda>
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On Fri, Apr 02, 2021 at 02:47:23PM +0300, Dan Carpenter wrote:
> The nla_len() is less than or equal to 16.  If it's less than 16 then
> end of the "gid" buffer is uninitialized.
> 
> Fixes: ae43f8286730 ("IB/core: Add IP to GID netlink offload")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I just spotted this in review.  I think it's a bug but I'm not 100%.

I tend to agree with you, that it is a bug.

LS_NLA_TYPE_DGID is declared as NLA_BINARY which doesn't complain if
data is less than declared ".len". However, the fix needs to be in
ib_nl_is_good_ip_resp(), it shouldn't return "true" if length not equal
to 16.

Thanks