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Miller" , Eric Dumazet , Simon Horman , Shuah Khan , Hannes Frederic Sowa , Vadim Fedorenko , netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, Alice Mikityanska Subject: [PATCH net v2 0/2] Fix UDP length overflow in edge cases Date: Thu, 13 Aug 2026 15:03:49 +0300 Message-ID: <20260813120351.2807829-1-alice.kernel@fastmail.im> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Alice Mikityanska These are fixes for rare edge cases of 16-bit UDP length field overflow that might happen on netdevs with MTU >= 64k. Exposed by the new WARN added to udp_set_len_short, reported by syzbot. v1: https://lore.kernel.org/netdev/20260805205957.1652619-1-alice.kernel@fastmail.im/ Alice Mikityanska (2): net: Fix UDP length overflow with PMTU discover and big MTU net: ipv6: Clamp to IP6_MAX_MTU in ip6_dst_mtu_maybe_forward include/net/ip6_route.h | 2 + net/ipv4/ip_output.c | 2 + net/ipv6/ip6_output.c | 2 +- tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/cork_fragsize.py | 77 ++++++++++++++++++++ 5 files changed, 83 insertions(+), 1 deletion(-) create mode 100755 tools/testing/selftests/net/cork_fragsize.py -- 2.55.0