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Date: Fri, 3 Jan 2025 18:14:31 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Shiming Cheng <shiming.cheng@mediatek.com>
Cc: <willemdebruijn.kernel@gmail.com>, <davem@davemloft.net>,
 <dsahern@kernel.org>, <edumazet@google.com>, <pabeni@redhat.com>,
 <horms@kernel.org>, <matthias.bgg@gmail.com>,
 <angelogioacchino.delregno@collabora.com>, <linux-kernel@vger.kernel.org>,
 <linux-arm-kernel@lists.infradead.org>,
 <linux-mediatek@lists.infradead.org>, <netdev@vger.kernel.org>,
 <lena.wang@mediatek.com>
Subject: Re: [PATCH net v2] ipv6: socket SO_BINDTODEVICE lookup routing fail
 without IPv6 rule.
Message-ID: <20250103181431.536909ad@kernel.org>
In-Reply-To: <20250103054413.31581-1-shiming.cheng@mediatek.com>
References: <20250103054413.31581-1-shiming.cheng@mediatek.com>
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On Fri, 3 Jan 2025 13:43:49 +0800 Shiming Cheng wrote:
> When using socket IPv6 with SO_BINDTODEVICE, if IPv6 rule is not
> matched, it will return ENETUNREACH. In fact, IPv4 does not behave
> this way. IPv4 prioritizes looking up IP rules for routing and
> forwarding, if not matched it will use socket-bound out interface
> to send packets. The modification here is to make IPv6 behave the
> same as IPv4. If IP rule is not found, it will also use socket-bound
> out interface to send packts.

CI shows failures in tools/testing/selftests/net/fcnal-test.sh
and tools/testing/selftests/net/fib_nexthops.sh with this patch
applied. Could be a flake but please double check before sending v3