Andrii Nakryiko | e2b5cfc | 2023-02-15 20:59:54 -0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ |
| 3 | #include "vmlinux.h" |
| 4 | #include <bpf/bpf_helpers.h> |
| 5 | #include <bpf/bpf_tracing.h> |
| 6 | #include <bpf/bpf_core_read.h> |
| 7 | #include "bpf_misc.h" |
| 8 | |
| 9 | char _license[] SEC("license") = "GPL"; |
| 10 | |
| 11 | static long stack[256]; |
| 12 | |
| 13 | /* |
| 14 | * KPROBE contexts |
| 15 | */ |
| 16 | |
| 17 | __weak int kprobe_typedef_ctx_subprog(bpf_user_pt_regs_t *ctx) |
| 18 | { |
| 19 | return bpf_get_stack(ctx, &stack, sizeof(stack), 0); |
| 20 | } |
| 21 | |
| 22 | SEC("?kprobe") |
| 23 | __success |
| 24 | int kprobe_typedef_ctx(void *ctx) |
| 25 | { |
| 26 | return kprobe_typedef_ctx_subprog(ctx); |
| 27 | } |
| 28 | |
| 29 | #define pt_regs_struct_t typeof(*(__PT_REGS_CAST((struct pt_regs *)NULL))) |
| 30 | |
| 31 | __weak int kprobe_struct_ctx_subprog(pt_regs_struct_t *ctx) |
| 32 | { |
| 33 | return bpf_get_stack((void *)ctx, &stack, sizeof(stack), 0); |
| 34 | } |
| 35 | |
| 36 | SEC("?kprobe") |
| 37 | __success |
| 38 | int kprobe_resolved_ctx(void *ctx) |
| 39 | { |
| 40 | return kprobe_struct_ctx_subprog(ctx); |
| 41 | } |
| 42 | |
| 43 | /* this is current hack to make this work on old kernels */ |
| 44 | struct bpf_user_pt_regs_t {}; |
| 45 | |
| 46 | __weak int kprobe_workaround_ctx_subprog(struct bpf_user_pt_regs_t *ctx) |
| 47 | { |
| 48 | return bpf_get_stack(ctx, &stack, sizeof(stack), 0); |
| 49 | } |
| 50 | |
| 51 | SEC("?kprobe") |
| 52 | __success |
| 53 | int kprobe_workaround_ctx(void *ctx) |
| 54 | { |
| 55 | return kprobe_workaround_ctx_subprog(ctx); |
| 56 | } |
| 57 | |
| 58 | /* |
| 59 | * RAW_TRACEPOINT contexts |
| 60 | */ |
| 61 | |
| 62 | __weak int raw_tp_ctx_subprog(struct bpf_raw_tracepoint_args *ctx) |
| 63 | { |
| 64 | return bpf_get_stack(ctx, &stack, sizeof(stack), 0); |
| 65 | } |
| 66 | |
| 67 | SEC("?raw_tp") |
| 68 | __success |
| 69 | int raw_tp_ctx(void *ctx) |
| 70 | { |
| 71 | return raw_tp_ctx_subprog(ctx); |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * RAW_TRACEPOINT_WRITABLE contexts |
| 76 | */ |
| 77 | |
| 78 | __weak int raw_tp_writable_ctx_subprog(struct bpf_raw_tracepoint_args *ctx) |
| 79 | { |
| 80 | return bpf_get_stack(ctx, &stack, sizeof(stack), 0); |
| 81 | } |
| 82 | |
| 83 | SEC("?raw_tp") |
| 84 | __success |
| 85 | int raw_tp_writable_ctx(void *ctx) |
| 86 | { |
| 87 | return raw_tp_writable_ctx_subprog(ctx); |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * PERF_EVENT contexts |
| 92 | */ |
| 93 | |
| 94 | __weak int perf_event_ctx_subprog(struct bpf_perf_event_data *ctx) |
| 95 | { |
| 96 | return bpf_get_stack(ctx, &stack, sizeof(stack), 0); |
| 97 | } |
| 98 | |
| 99 | SEC("?perf_event") |
| 100 | __success |
| 101 | int perf_event_ctx(void *ctx) |
| 102 | { |
| 103 | return perf_event_ctx_subprog(ctx); |
| 104 | } |