Re: Issue with iwd + Linux 5.8.3 + WPA Enterprise

From: Herbert Xu
Date: Wed Aug 26 2020 - 10:19:41 EST


On Wed, Aug 26, 2020 at 08:57:17AM -0500, Denis Kenzior wrote:
>
> I'm just waking up now, so I might seem dense, but for my education, can you
> tell me why we need to set MSG_MORE when we issue just a single sendmsg
> followed immediately by recv/recvmsg? ell/iwd operates on small buffers, so
> we don't really feed the kernel data in multiple send operations. You can
> see this in the ell git tree link referenced in Andrew's reply.

You obviously don't need MSG_MORE if you're doing a single sendmsg.

The problematic code is in l_cipher_set_iv. It does a sendmsg(2)
that expects to be followed by more sendmsg(2) calls before a
recvmsg(2). That's the one that needs a MSG_MORE.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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