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Date: Mon, 21 Aug 2023 19:11:13 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Kuniyuki Iwashima
 <kuni1840@gmail.com>, <netdev@vger.kernel.org>
Subject: Re: [PATCH v1 net] net: Allow larger buffer than peer address for
 SO_PEERNAME.
Message-ID: <20230821191113.72311580@kernel.org>
In-Reply-To: <20230819005552.39751-1-kuniyu@amazon.com>
References: <20230819005552.39751-1-kuniyu@amazon.com>
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On Fri, 18 Aug 2023 17:55:52 -0700 Kuniyuki Iwashima wrote:
> For example, we usually do not know the peer name if we get an AF_UNIX
> socket by accept(), FD passing, or pidfd_getfd().  Then we get -EINVAL
> if we pass sizeof(struct sockaddr_un) to getsockopt(SO_PEERNAME).  So,
> we need to do binary search to get the exact peer name.

Sounds annoying indeed, but is it really a fix?