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From: Rich Felker <dalias@libc.org>
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Subject: Re: Need to zero pads in msghdr
Date: Wed, 25 Jan 2017 12:00:48 -0500
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On Wed, Jan 25, 2017 at 08:42:52AM -0800, Andrei Vagin wrote:
> Hi,
> 
> In this patch
> http://git.musl-libc.org/cgit/musl/commit/arch/x86_64/bits/socket.h?id=7168790763cdeb794df52be6e3b39fbb021c5a64
> you suppose that the kernel ignores the upper 32 bits of msg_iovlen,
> but it doesn't, so pads in msghdr structures have to be zeroed before
> calling sendmsg and recvmsg syscalls.
> 
> https://github.com/xemul/criu/issues/276

sendmsg and recvmsg perform this zeroing. If it's not working there
must be some more subtle cause.

Rich