From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Sat, 27 Apr 2024 12:05:51 +0200
Subject: Adding upstream version 5.10.209.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 .../testing/selftests/bpf/progs/test_pkt_access.c  | 150 +++++++++++++++++++++
 1 file changed, 150 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/progs/test_pkt_access.c

(limited to 'tools/testing/selftests/bpf/progs/test_pkt_access.c')

diff --git a/tools/testing/selftests/bpf/progs/test_pkt_access.c b/tools/testing/selftests/bpf/progs/test_pkt_access.c
new file mode 100644
index 000000000..852051064
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_pkt_access.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2017 Facebook
+ */
+#include <stddef.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/in.h>
+#include <linux/tcp.h>
+#include <linux/pkt_cls.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+#define barrier() __asm__ __volatile__("": : :"memory")
+int _version SEC("version") = 1;
+
+/* llvm will optimize both subprograms into exactly the same BPF assembly
+ *
+ * Disassembly of section .text:
+ *
+ * 0000000000000000 test_pkt_access_subprog1:
+ * ; 	return skb->len * 2;
+ *        0:	61 10 00 00 00 00 00 00	r0 = *(u32 *)(r1 + 0)
+ *        1:	64 00 00 00 01 00 00 00	w0 <<= 1
+ *        2:	95 00 00 00 00 00 00 00	exit
+ *
+ * 0000000000000018 test_pkt_access_subprog2:
+ * ; 	return skb->len * val;
+ *        3:	61 10 00 00 00 00 00 00	r0 = *(u32 *)(r1 + 0)
+ *        4:	64 00 00 00 01 00 00 00	w0 <<= 1
+ *        5:	95 00 00 00 00 00 00 00	exit
+ *
+ * Which makes it an interesting test for BTF-enabled verifier.
+ */
+static __attribute__ ((noinline))
+int test_pkt_access_subprog1(volatile struct __sk_buff *skb)
+{
+	return skb->len * 2;
+}
+
+static __attribute__ ((noinline))
+int test_pkt_access_subprog2(int val, volatile struct __sk_buff *skb)
+{
+	return skb->len * val;
+}
+
+#define MAX_STACK (512 - 2 * 32)
+
+__attribute__ ((noinline))
+int get_skb_len(struct __sk_buff *skb)
+{
+	volatile char buf[MAX_STACK] = {};
+
+	return skb->len;
+}
+
+__attribute__ ((noinline))
+int get_constant(long val)
+{
+	return val - 122;
+}
+
+int get_skb_ifindex(int, struct __sk_buff *skb, int);
+
+__attribute__ ((noinline))
+int test_pkt_access_subprog3(int val, struct __sk_buff *skb)
+{
+	return get_skb_len(skb) * get_skb_ifindex(val, skb, get_constant(123));
+}
+
+__attribute__ ((noinline))
+int get_skb_ifindex(int val, struct __sk_buff *skb, int var)
+{
+	volatile char buf[MAX_STACK] = {};
+
+	return skb->ifindex * val * var;
+}
+
+__attribute__ ((noinline))
+int test_pkt_write_access_subprog(struct __sk_buff *skb, __u32 off)
+{
+	void *data = (void *)(long)skb->data;
+	void *data_end = (void *)(long)skb->data_end;
+	struct tcphdr *tcp = NULL;
+
+	if (off > sizeof(struct ethhdr) + sizeof(struct ipv6hdr))
+		return -1;
+
+	tcp = data + off;
+	if (tcp + 1 > data_end)
+		return -1;
+	/* make modification to the packet data */
+	tcp->check++;
+	return 0;
+}
+
+SEC("classifier/test_pkt_access")
+int test_pkt_access(struct __sk_buff *skb)
+{
+	void *data_end = (void *)(long)skb->data_end;
+	void *data = (void *)(long)skb->data;
+	struct ethhdr *eth = (struct ethhdr *)(data);
+	struct tcphdr *tcp = NULL;
+	__u8 proto = 255;
+	__u64 ihl_len;
+
+	if (eth + 1 > data_end)
+		return TC_ACT_SHOT;
+
+	if (eth->h_proto == bpf_htons(ETH_P_IP)) {
+		struct iphdr *iph = (struct iphdr *)(eth + 1);
+
+		if (iph + 1 > data_end)
+			return TC_ACT_SHOT;
+		ihl_len = iph->ihl * 4;
+		proto = iph->protocol;
+		tcp = (struct tcphdr *)((void *)(iph) + ihl_len);
+	} else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) {
+		struct ipv6hdr *ip6h = (struct ipv6hdr *)(eth + 1);
+
+		if (ip6h + 1 > data_end)
+			return TC_ACT_SHOT;
+		ihl_len = sizeof(*ip6h);
+		proto = ip6h->nexthdr;
+		tcp = (struct tcphdr *)((void *)(ip6h) + ihl_len);
+	}
+
+	if (test_pkt_access_subprog1(skb) != skb->len * 2)
+		return TC_ACT_SHOT;
+	if (test_pkt_access_subprog2(2, skb) != skb->len * 2)
+		return TC_ACT_SHOT;
+	if (test_pkt_access_subprog3(3, skb) != skb->len * 3 * skb->ifindex)
+		return TC_ACT_SHOT;
+	if (tcp) {
+		if (test_pkt_write_access_subprog(skb, (void *)tcp - data))
+			return TC_ACT_SHOT;
+		if (((void *)(tcp) + 20) > data_end || proto != 6)
+			return TC_ACT_SHOT;
+		barrier(); /* to force ordering of checks */
+		if (((void *)(tcp) + 18) > data_end)
+			return TC_ACT_SHOT;
+		if (tcp->urg_ptr == 123)
+			return TC_ACT_OK;
+	}
+
+	return TC_ACT_UNSPEC;
+}
-- 
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