1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <stddef.h> 3 #include <linux/bpf.h> 4 #include <bpf/bpf_helpers.h> 5 6 struct S { 7 int x; 8 }; 9 10 struct C { 11 int x; 12 int y; 13 }; 14 15 struct { 16 __uint(type, BPF_MAP_TYPE_ARRAY); 17 __uint(max_entries, 1); 18 __type(key, __u32); 19 __type(value, struct S); 20 } map SEC(".maps"); 21 22 enum E { 23 E_ITEM 24 }; 25 26 static int global_data_x = 100; 27 static int volatile global_data_y = 500; 28 29 __noinline int foo(const struct S *s) 30 { 31 if (s) 32 return bpf_get_prandom_u32() < s->x; 33 34 return 0; 35 } 36 37 __noinline int bar(int *x) 38 { 39 if (x) 40 *x &= bpf_get_prandom_u32(); 41 42 return 0; 43 } 44 __noinline int baz(volatile int *x) 45 { 46 if (x) 47 *x &= bpf_get_prandom_u32(); 48 49 return 0; 50 } 51 52 __noinline int qux(enum E *e) 53 { 54 if (e) 55 return *e; 56 57 return 0; 58 } 59 60 __noinline int quux(int (*arr)[10]) 61 { 62 if (arr) 63 return (*arr)[9]; 64 65 return 0; 66 } 67 68 __noinline int quuz(int **p) 69 { 70 if (p) 71 *p = NULL; 72 73 return 0; 74 } 75 76 SEC("cgroup_skb/ingress") 77 int test_cls(struct __sk_buff *skb) 78 { 79 int result = 0; 80 81 { 82 const struct S s = {.x = skb->len }; 83 84 result |= foo(&s); 85 } 86 87 { 88 const __u32 key = 1; 89 const struct S *s = bpf_map_lookup_elem(&map, &key); 90 91 result |= foo(s); 92 } 93 94 { 95 const struct C c = {.x = skb->len, .y = skb->family }; 96 97 result |= foo((const struct S *)&c); 98 } 99 100 { 101 result |= foo(NULL); 102 } 103 104 { 105 bar(&result); 106 bar(&global_data_x); 107 } 108 109 { 110 result |= baz(&global_data_y); 111 } 112 113 { 114 enum E e = E_ITEM; 115 116 result |= qux(&e); 117 } 118 119 { 120 int array[10] = {0}; 121 122 result |= quux(&array); 123 } 124 125 { 126 int *p; 127 128 result |= quuz(&p); 129 } 130 131 return result ? 1 : 0; 132 } 133