netdev - Re: [PATCH] bpf: tcp_bpf_recvmsg should return EAGAIN when nonblocking and no data

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] [day] [month] [year] [list]

Date:   Tue, 30 Oct 2018 23:30:59 +0100
From:   Daniel Borkmann <daniel@...earbox.net>
To:     John Fastabend <john.fastabend@...il.com>, ast@...nel.org
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH] bpf: tcp_bpf_recvmsg should return EAGAIN when
 nonblocking and no data

On 10/29/2018 08:31 PM, John Fastabend wrote:
> We return 0 in the case of a nonblocking socket that has no data
> available. However, this is incorrect and may confuse applications.
> After this patch we do the correct thing and return the error
> EAGAIN.
> 
> Quoting return codes from recvmsg manpage,
> 
> EAGAIN or EWOULDBLOCK
>  The socket is marked nonblocking and the receive operation would
>  block, or a receive timeout had been set and the timeout expired
>  before data was received.
> 
> Signed-off-by: John Fastabend <john.fastabend@...il.com>

Applied to bpf, thanks!