Re: [PATCH v1 net 1/2] tcp: Fix bind() conflict check for dual-stack wildcard address. - Linux regression tracking (Thorsten Leemhuis)

From: "Linux regression tracking (Thorsten Leemhuis)"  <regressions@leemhuis.info>
To: Kuniyuki Iwashima <kuniyu@amazon.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	David Ahern <dsahern@kernel.org>
Cc: Kuniyuki Iwashima <kuni1840@gmail.com>,
	netdev@vger.kernel.org, Paul Holzinger <pholzing@redhat.com>,
	Martin KaFai Lau <martin.lau@kernel.org>
Subject: Re: [PATCH v1 net 1/2] tcp: Fix bind() conflict check for dual-stack wildcard address.
Date: Sun, 12 Mar 2023 12:42:48 +0100	[thread overview]
Message-ID: <533d3c1a-db7e-6ff2-1fdf-fb8bbbb7a14c@leemhuis.info> (raw)
In-Reply-To: <20230312031904.4674-2-kuniyu@amazon.com>

Thx for working on this. There is one small detail to improve:

On 12.03.23 04:19, Kuniyuki Iwashima wrote:
> Paul Holzinger reported [0] that commit 5456262d2baa ("net: Fix
> incorrect address comparison when searching for a bind2 bucket")
> introduced a bind() regression.  Paul also gave a nice repro that
> calls two types of bind() on the same port, both of which now
> succeed, but the second call should fail:
> 
>   bind(fd1, ::, port) + bind(fd2, 127.0.0.1, port)
> 
> The cited commit added address family tests in three functions to
> fix the uninit-value KMSAN report. [1]  However, the test added to
> inet_bind2_bucket_match_addr_any() removed a necessary conflict
> check; the dual-stack wildcard address no longer conflicts with
> an IPv4 non-wildcard address.
> 
> If tb->family is AF_INET6 and sk->sk_family is AF_INET in
> inet_bind2_bucket_match_addr_any(), we still need to check
> if tb has the dual-stack wildcard address.
> 
> Note that the IPv4 wildcard address does not conflict with
> IPv6 non-wildcard addresses.
> 
> [0]: https://lore.kernel.org/netdev/e21bf153-80b0-9ec0-15ba-e04a4ad42c34@redhat.com/
> [1]: https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv-ijN-A@mail.gmail.com/
> 
> Fixes: 5456262d2baa ("net: Fix incorrect address comparison when searching for a bind2 bucket")
> Reported-by: Paul Holzinger <pholzing@redhat.com>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>

The links above should use proper link tags, this thus ideally should
look something like this:

Link:
https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv-ijN-A@mail.gmail.com/
[1]
Fixes: 5456262d2baa ("net: Fix incorrect address comparison when
searching for a bind2 bucket")
Reported-by: Paul Holzinger <pholzing@redhat.com>
Link:
https://lore.kernel.org/netdev/e21bf153-80b0-9ec0-15ba-e04a4ad42c34@redhat.com/
[0]

[placing the link [1] at the end would be fine, too]

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
If I did something stupid, please tell me, as explained on that page.

P.S.: While at it:

#regzbot ^backmonitor:
https://lore.kernel.org/netdev/e21bf153-80b0-9ec0-15ba-e04a4ad42c34@redhat.com/