Commit 0c8bbf99 authored by Alexei Starovoitov's avatar Alexei Starovoitov Committed by Andrii Nakryiko
Browse files

selftests/bpf: Test may_goto 



Add tests for may_goto instruction via cond_break macro.

Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Tested-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240306031929.42666-5-alexei.starovoitov@gmail.com
parent 06375801

tools/testing/selftests/bpf/DENYLIST.s390x

+1 −0
Original line number Diff line number Diff line
@@ -3,3 +3,4 @@ 
exceptions				 # JIT does not support calling kfunc bpf_throw				       (exceptions)

get_stack_raw_tp                         # user_stack corrupted user stack                                             (no backchain userspace)

stacktrace_build_id                      # compare_map_keys stackid_hmap vs. stackmap err -2 errno 2                   (?)

verifier_iterating_callbacks

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

+100 −3
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include "bpf_misc.h"

#include "bpf_experimental.h"



struct {

	__uint(type, BPF_MAP_TYPE_ARRAY);
@@ -239,4 +237,103 @@ int bpf_loop_iter_limit_nested(void *unused) 
	return 1000 * a + b + c;

}



#define ARR_SZ 1000000

int zero;

char arr[ARR_SZ];



SEC("socket")

__success __retval(0xd495cdc0)

int cond_break1(const void *ctx)

{

	unsigned long i;

	unsigned int sum = 0;



	for (i = zero; i < ARR_SZ; cond_break, i++)

		sum += i;

	for (i = zero; i < ARR_SZ; i++) {

		barrier_var(i);

		sum += i + arr[i];

		cond_break;

	}



	return sum;

}



SEC("socket")

__success __retval(999000000)

int cond_break2(const void *ctx)

{

	int i, j;

	int sum = 0;



	for (i = zero; i < 1000; cond_break, i++)

		for (j = zero; j < 1000; j++) {

			sum += i + j;

			cond_break;

		}



	return sum;

}



static __noinline int loop(void)

{

	int i, sum = 0;



	for (i = zero; i <= 1000000; i++, cond_break)

		sum += i;



	return sum;

}



SEC("socket")

__success __retval(0x6a5a2920)

int cond_break3(const void *ctx)

{

	return loop();

}



SEC("socket")

__success __retval(1)

int cond_break4(const void *ctx)

{

	int cnt = zero;



	for (;;) {

		/* should eventually break out of the loop */

		cond_break;

		cnt++;

	}

	/* if we looped a bit, it's a success */

	return cnt > 1 ? 1 : 0;

}



static __noinline int static_subprog(void)

{

	int cnt = zero;



	for (;;) {

		cond_break;

		cnt++;

	}



	return cnt;

}



SEC("socket")

__success __retval(1)

int cond_break5(const void *ctx)

{

	int cnt1 = zero, cnt2;



	for (;;) {

		cond_break;

		cnt1++;

	}



	cnt2 = static_subprog();



	/* main and subprog have to loop a bit */

	return cnt1 > 1 && cnt2 > 1 ? 1 : 0;

}



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