1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2019 Facebook 3 4 #include <linux/bpf.h> 5 #include <stdint.h> 6 #include <bpf/bpf_helpers.h> 7 #include <bpf/bpf_core_read.h> 8 9 char _license[] SEC("license") = "GPL"; 10 11 struct { 12 char in[256]; 13 char out[256]; 14 } data = {}; 15 16 struct core_reloc_flavors { 17 int a; 18 int b; 19 int c; 20 }; 21 22 /* local flavor with reversed layout */ 23 struct core_reloc_flavors___reversed { 24 int c; 25 int b; 26 int a; 27 }; 28 29 /* local flavor with nested/overlapping layout */ 30 struct core_reloc_flavors___weird { 31 struct { 32 int b; 33 }; 34 /* a and c overlap in local flavor, but this should still work 35 * correctly with target original flavor 36 */ 37 union { 38 int a; 39 int c; 40 }; 41 }; 42 43 #define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src) 44 45 SEC("raw_tracepoint/sys_enter") 46 int test_core_flavors(void *ctx) 47 { 48 struct core_reloc_flavors *in_orig = (void *)&data.in; 49 struct core_reloc_flavors___reversed *in_rev = (void *)&data.in; 50 struct core_reloc_flavors___weird *in_weird = (void *)&data.in; 51 struct core_reloc_flavors *out = (void *)&data.out; 52 53 /* read a using weird layout */ 54 if (CORE_READ(&out->a, &in_weird->a)) 55 return 1; 56 /* read b using reversed layout */ 57 if (CORE_READ(&out->b, &in_rev->b)) 58 return 1; 59 /* read c using original layout */ 60 if (CORE_READ(&out->c, &in_orig->c)) 61 return 1; 62 63 return 0; 64 } 65 66