Commit e2b5cfc9 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
Browse files

selftests/bpf: Add global subprog context passing tests 



Add tests validating that it's possible to pass context arguments into
global subprogs for various types of programs, including a particularly
tricky KPROBE programs (which cover kprobes, uprobes, USDTs, a vast and
important class of programs).

Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230216045954.3002473-4-andrii@kernel.org
parent 95ebb376

tools/testing/selftests/bpf/prog_tests/test_global_funcs.c

+2 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include "test_global_func15.skel.h"

#include "test_global_func16.skel.h"

#include "test_global_func17.skel.h"

#include "test_global_func_ctx_args.skel.h"



void test_test_global_funcs(void)

{
@@ -38,4 +39,5 @@ void test_test_global_funcs(void) 
	RUN_TESTS(test_global_func15);

	RUN_TESTS(test_global_func16);

	RUN_TESTS(test_global_func17);

	RUN_TESTS(test_global_func_ctx_args);

}

tools/testing/selftests/bpf/progs/test_global_func_ctx_args.c

0 → 100644
+104 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */

#include "vmlinux.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>

#include <bpf/bpf_core_read.h>

#include "bpf_misc.h"



char _license[] SEC("license") = "GPL";



static long stack[256];



/*

 * KPROBE contexts

 */



__weak int kprobe_typedef_ctx_subprog(bpf_user_pt_regs_t *ctx)

{

	return bpf_get_stack(ctx, &stack, sizeof(stack), 0);

}



SEC("?kprobe")

__success

int kprobe_typedef_ctx(void *ctx)

{

	return kprobe_typedef_ctx_subprog(ctx);

}



#define pt_regs_struct_t typeof(*(__PT_REGS_CAST((struct pt_regs *)NULL)))



__weak int kprobe_struct_ctx_subprog(pt_regs_struct_t *ctx)

{

	return bpf_get_stack((void *)ctx, &stack, sizeof(stack), 0);

}



SEC("?kprobe")

__success

int kprobe_resolved_ctx(void *ctx)

{

	return kprobe_struct_ctx_subprog(ctx);

}



/* this is current hack to make this work on old kernels */

struct bpf_user_pt_regs_t {};



__weak int kprobe_workaround_ctx_subprog(struct bpf_user_pt_regs_t *ctx)

{

	return bpf_get_stack(ctx, &stack, sizeof(stack), 0);

}



SEC("?kprobe")

__success

int kprobe_workaround_ctx(void *ctx)

{

	return kprobe_workaround_ctx_subprog(ctx);

}



/*

 * RAW_TRACEPOINT contexts

 */



__weak int raw_tp_ctx_subprog(struct bpf_raw_tracepoint_args *ctx)

{

	return bpf_get_stack(ctx, &stack, sizeof(stack), 0);

}



SEC("?raw_tp")

__success

int raw_tp_ctx(void *ctx)

{

	return raw_tp_ctx_subprog(ctx);

}



/*

 * RAW_TRACEPOINT_WRITABLE contexts

 */



__weak int raw_tp_writable_ctx_subprog(struct bpf_raw_tracepoint_args *ctx)

{

	return bpf_get_stack(ctx, &stack, sizeof(stack), 0);

}



SEC("?raw_tp")

__success

int raw_tp_writable_ctx(void *ctx)

{

	return raw_tp_writable_ctx_subprog(ctx);

}



/*

 * PERF_EVENT contexts

 */



__weak int perf_event_ctx_subprog(struct bpf_perf_event_data *ctx)

{

	return bpf_get_stack(ctx, &stack, sizeof(stack), 0);

}



SEC("?perf_event")

__success

int perf_event_ctx(void *ctx)

{

	return perf_event_ctx_subprog(ctx);

}