From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pz2-f42.google.com (mail-pz2-f42.google.com [74.125.228.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B6D504E73DE for ; Mon, 21 Sep 2026 17:40:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.228.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790012402; cv=none; b=QXNpS7nqU85F2v+d/fENu0h/a6Oh+sgxR9dXymnZDTxjB6YBLwLflBgsaRohiANQRXwus5E0rfywOxC61pbhBby+Kqvr/sL+nS+bwAfEBUYz4C4kR+rghJUcIwTx8G2Sw0lsYn6wrMMZs/7jsWiDjYpr6bG60wRCC3vfcGZMcFo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790012402; c=relaxed/simple; bh=G6MYpOzFS9oaQMkxPkHjP9bTWZdWzUL4Wm5DCp+oCjw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G3k2JYZUvqT6/P5xcDBUjav8K+6aVfAVB09OhcE10JjOxbMIMdRjSHNaM8x3J99JT13bj985zd9cSq1KrfjJ98osWX6xFq1cjjWYwctS4pluB3909vWxZGNjzG3aLNpIOHhP0eIeBLBEoR7F7TO5nBiZHwU5bFFrhq/9wWybFqo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=kZaRz6wc; arc=none smtp.client-ip=74.125.228.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kZaRz6wc" Received: by mail-pz2-f42.google.com with SMTP id 41be03b00d2f7-cc1cea50dc0so1401349a12.2 for ; Mon, 21 Sep 2026 10:40:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790012400; x=1790617200; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=9eJ58EFzv+KbS2BjBvEgqqhI69SkKi+v+DcklYWB+/8=; b=kZaRz6wcdpyS4w1YAvdChMzOmhQ6BOMMlkGfeeFkipwbEuEhKnVR2aEPoYIrYzlx0g mzkqgWiZXKVpvSl6eUw0EW7g6dDx6yIWonhhmC6Vk1YmQiHh2my84aIFh4D1MifC4Xcs W3nppw7NJdFhSXQNN/LrLFXC8k1D3KLBUg+ktJHlUr9eXRJ8hFaXTfXEM/KYNXquFR4J bcngKiI8NURVLWoQbZpRl8dgxP2yxbkp77tJT1n263lRZZ4wlwhgxc5ziz0BZuSXnuyV C0JaeCc9m7Yxc88r+u5UJlriKGO6qDk+YR24LWCq37h64z4aq3KzT69jRxvqKh1A015O 1vcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790012400; x=1790617200; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=9eJ58EFzv+KbS2BjBvEgqqhI69SkKi+v+DcklYWB+/8=; b=uGd5209qIx9GXOEHOFsUVXKCE8c9Ojm0Ud93ZoHqTtWpS/TFa3pc+mDdlnm9O3Y67I UFwMnvQtLCoAbb1NbrMs1OYML/wCPbfYKyeABq4SBSw64ue59hA59+5dCzEauN61/RFt LSHoPeukJD9VfaAHNuFpqfUZc3UF96I+e7AfWV+83iBUqH/I46FVgRUl/5y5gZZ+wEiL 0TY9HQlEs+Gfj4OspXo1c4Gl3KYDbAiFLdO9ZDiMn+Xy3kCTt0kR6ArlqbHkZlkYWdsY qYa4ch509FKmTLiOubQUwLjxvMr3lHyY+sAq0lDWa+Capia45lyhGgLVpyefpgSylLPr wKHQ== X-Forwarded-Encrypted: i=1; AKwUvBzfnGHmbTaee0tCts58IBj4dy+HetbGfuNEl8XQ857h7qr5wll3m/LzFDX8tw67UvlWmGo6I6wsiDfQgYY=@vger.kernel.org X-Gm-Message-State: AFuF++kPo7EaGGwzd8a7OZxA+etUXmcpBAWO8L7T/7pL/CWqyc1+3jF8 XU6fZsxfnZuW0Z07YM3F4mn7iZNpZ8Pj5mHKjHaB9qWvwsPRngvkNWe6 X-Gm-Gg: AYBFou1mDdKqQFfOsQ4Xzp/Cq798zLyv/qL7CJRwremPeTDWH8hrPLRoTIofXNM3t5T Hef+IMf1lmPL23ODC9jCqbdAfiBI1xHbTJGcI5LsShmatrGx9uyoVy1w9Y6JB2ru5GS3FDaoHIP pKCfcHGI8JqAQUXPqC3gOip9bPLduPWcjSvNkHMSC/DoSllDuzIUQRvqkh6JEjCLXwDEz1/OGvw Re5sxaak9qYUKyh+BZjH3wbWjGdlkGwYaZ+1ux6PqM4htG7n9+Q6k0eLDjDFoZt7jhL/RwnqxE4 8+oLAYDPW73xtJu+t8gwRBM1SkeZXFqUU2y/Nx2ef15zSitAozNTLdAsFCFuC+kkVrKxFzM7vUR NqfqSM8ZVSdKg+nT1fazV/RKnBm7RX/lb3rJNtQtJ6CmpEX/IAdLTtdMx5wWveFvL74C8IothJo InQGOAizOZLHgM0qfd+8x7p2X+gwsZ1yHz7nz20aQm+r7XrIPIp3pEtOlpdUDSqHHABy+OEPfF4 p5mmiYcYmnK/rBHL/p3xPzfvvrURmNn X-Received: by 2002:a05:6a20:439f:b0:3d1:af47:5f80 with SMTP id adf61e73a8af0-3dd8c405d09mr19804538637.11.1790012399706; Mon, 21 Sep 2026 10:39:59 -0700 (PDT) Received: from 192.168.50.3 ([198.176.50.208]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-cc72af0955esm3986985a12.32.2026.09.21.10.39.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Sep 2026 10:39:59 -0700 (PDT) From: Weiming Shi To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Martin KaFai Lau , Song Liu , Yonghong Song , Jiri Olsa , Emil Tsalapatis , Ihor Solodrai , John Fastabend , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Shuah Khan Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, Xiang Mei , Weiming Shi Subject: [PATCH v4 2/2] selftests/bpf: cover stale CB after LWT IP encapsulation Date: Tue, 22 Sep 2026 01:39:10 +0800 Message-ID: <20260921173910.90847-3-bestswngs@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260921173910.90847-1-bestswngs@gmail.com> References: <20260921173910.90847-1-bestswngs@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add compact regression coverage to the existing LWT IP encapsulation test. Send an IPv4 ping with a Record Route option through an ingress LWT program which prepends a TTL-one IPv4 header, then observe __icmp_send() with fentry and verify that the restored protocol control block no longer contains the inner header's cached option offsets. Read ctx->cb[0] in the LWT program so the test exercises bpf_prog_run_save_cb()'s save/restore path before the post-run check. Link: https://lore.kernel.org/bpf/DLKB3UXOH0IS.1UL8NV9HSJFXG@gmail.com/ Signed-off-by: Weiming Shi --- .../selftests/bpf/prog_tests/lwt_ip_encap.c | 45 ++++++++++++++++++ .../selftests/bpf/progs/test_lwt_ip_encap.c | 47 +++++++++++++++++++ 2 files changed, 92 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/lwt_ip_encap.c b/tools/testing/selftests/bpf/prog_tests/lwt_ip_encap.c index 39e8a3b8b6af..14ba33eaeb96 100644 --- a/tools/testing/selftests/bpf/prog_tests/lwt_ip_encap.c +++ b/tools/testing/selftests/bpf/prog_tests/lwt_ip_encap.c @@ -686,3 +686,48 @@ void test_lwt_ip_encap_vxlan_ipv6(void) { lwt_ip_encap_vxlan(IPV6_ENCAP); } + +void test_lwt_ip_encap_stale_cb(void) +{ + char ns1[NETNS_NAME_SIZE] = NETNS_BASE "-1-"; + char ns2[NETNS_NAME_SIZE] = NETNS_BASE "-2-"; + char ns3[NETNS_NAME_SIZE] = NETNS_BASE "-3-"; + struct test_lwt_ip_encap *skel = NULL; + + if (!ASSERT_OK(create_ns(ns1, NETNS_NAME_SIZE), "create ns1")) + goto out; + if (!ASSERT_OK(create_ns(ns2, NETNS_NAME_SIZE), "create ns2")) + goto out; + if (!ASSERT_OK(create_ns(ns3, NETNS_NAME_SIZE), "create ns3")) + goto out; + if (!ASSERT_OK(setup_network(ns1, ns2, ns3, ""), "setup network")) + goto out; + + skel = test_lwt_ip_encap__open(); + if (!ASSERT_OK_PTR(skel, "open")) + goto out; + bpf_program__set_autoload(skel->progs.bpf_lwt_encap_gre, false); + bpf_program__set_autoload(skel->progs.bpf_lwt_encap_gre6, false); + bpf_program__set_autoload(skel->progs.bpf_lwt_encap_vxlan, false); + bpf_program__set_autoload(skel->progs.bpf_lwt_encap_vxlan6, false); + bpf_program__set_autoload(skel->progs.bpf_lwt_encap_stale, false); + if (!ASSERT_OK(test_lwt_ip_encap__load(skel), "load")) + goto out; + if (!ASSERT_OK(test_lwt_ip_encap__attach(skel), "attach")) + goto out; + + SYS(out, "ip -n %s route replace %s/32 encap bpf in obj %s sec encap_stale dev veth3", + ns2, IP4_ADDR_DST, BPF_FILE); + skel->bss->stale_cb_seen = false; + skel->bss->stale_cb_cleared = false; + SYS_NOFAIL("ip netns exec %s ping -q -R -c 1 -W 1 -I veth1 %s >/dev/null 2>&1", + ns1, IP4_ADDR_DST); + ASSERT_TRUE(skel->bss->stale_cb_seen, "stale_cb_seen"); + ASSERT_TRUE(skel->bss->stale_cb_cleared, "stale_cb_cleared"); + +out: + test_lwt_ip_encap__destroy(skel); + SYS_NOFAIL("ip netns del %s", ns1); + SYS_NOFAIL("ip netns del %s", ns2); + SYS_NOFAIL("ip netns del %s", ns3); +} diff --git a/tools/testing/selftests/bpf/progs/test_lwt_ip_encap.c b/tools/testing/selftests/bpf/progs/test_lwt_ip_encap.c index 4a934fccf8f5..8b57c7fb7fa8 100644 --- a/tools/testing/selftests/bpf/progs/test_lwt_ip_encap.c +++ b/tools/testing/selftests/bpf/progs/test_lwt_ip_encap.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include "vmlinux.h" #include +#include #include #include #include @@ -10,6 +11,8 @@ struct grehdr { __be16 protocol; }; +#define ICMP_TIME_EXCEEDED 11 + SEC("encap_gre") int bpf_lwt_encap_gre(struct __sk_buff *skb) { @@ -80,6 +83,29 @@ int bpf_lwt_encap_gre6(struct __sk_buff *skb) return BPF_LWT_REROUTE; } +SEC("encap_stale") +int bpf_lwt_encap_stale(struct __sk_buff *skb) +{ + struct iphdr iph = {}; + + /* Exercise CB restore before post-run invalidation. */ + if (skb->cb[0]) + return BPF_DROP; + + iph.version = 4; + iph.ihl = 5; + iph.ttl = 1; + iph.protocol = IPPROTO_IPIP; + iph.tot_len = bpf_htons(skb->len + sizeof(iph)); + iph.saddr = bpf_htonl(0xac100264); /* 172.16.2.100 */ + iph.daddr = bpf_htonl(0xac100464); /* 172.16.4.100 */ + + if (bpf_lwt_push_encap(skb, BPF_LWT_ENCAP_IP, &iph, sizeof(iph))) + return BPF_DROP; + + return BPF_OK; +} + #define VXLAN_PORT 4789 #define VXLAN_FLAGS 0x08000000 #define VXLAN_VNI 1 @@ -194,6 +220,27 @@ volatile const int tgt_ip_version; __u16 transport_hdr = 0; __u16 network_hdr = 0; bool fexit_triggered = false; +bool stale_cb_cleared = false; +bool stale_cb_seen = false; + +SEC("fentry/__icmp_send") +int BPF_PROG(fentry_icmp_send, struct sk_buff *skb, int type, int code, + __be32 info, const struct inet_skb_parm *parm) +{ + struct iphdr *iph; + + if (type != ICMP_TIME_EXCEEDED) + return 0; + + iph = (void *)BPF_CORE_READ(skb, head) + BPF_CORE_READ(skb, network_header); + if (BPF_CORE_READ(iph, daddr) != bpf_htonl(0xac100464)) + return 0; + + stale_cb_seen = true; + stale_cb_cleared = !BPF_CORE_READ(parm, opt.optlen) && + !BPF_CORE_READ(parm, opt.rr); + return 0; +} SEC("?fexit/bpf_lwt_push_ip_encap") int BPF_PROG(fexit_lwt_push_ip_encap, struct sk_buff *skb, void *hdr, u32 len, bool ingress, -- 2.55.0