Commit e3f9bc35 authored by Jiri Olsa's avatar Jiri Olsa Committed by Andrii Nakryiko
Browse files

libbpf: Allow decimal offset for kprobes 



Allow to specify decimal offset in SEC macro, like:
  SEC("kprobe/bpf_fentry_test7+5")

Add selftest for that.

Suggested-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Reviewed-by: default avatarAlan Maguire <alan.maguire@oracle.com>
Tested-by: default avatarAlan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20210721215810.889975-3-jolsa@kernel.org
parent 1f71a468

tools/lib/bpf/libbpf.c

+1 −1
Original line number Diff line number Diff line
@@ -10424,7 +10424,7 @@ static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, 
	func_name = prog->sec_name + sec->len;

	opts.retprobe = strcmp(sec->sec, "kretprobe/") == 0;



	n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%lx", &func, &offset);

	n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset);

	if (n < 1) {

		err = -EINVAL;

		pr_warn("kprobe name is invalid: %s\n", func_name);

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

+2 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ void test_get_func_ip_test(void) 
	 */

#ifndef __x86_64__

	bpf_program__set_autoload(skel->progs.test6, false);

	bpf_program__set_autoload(skel->progs.test7, false);

#endif



	err = get_func_ip_test__load(skel);
@@ -46,6 +47,7 @@ void test_get_func_ip_test(void) 
	ASSERT_EQ(skel->bss->test5_result, 1, "test5_result");

#ifdef __x86_64__

	ASSERT_EQ(skel->bss->test6_result, 1, "test6_result");

	ASSERT_EQ(skel->bss->test7_result, 1, "test7_result");

#endif



cleanup:

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

+11 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ extern const void bpf_fentry_test3 __ksym; 
extern const void bpf_fentry_test4 __ksym;

extern const void bpf_modify_return_test __ksym;

extern const void bpf_fentry_test6 __ksym;

extern const void bpf_fentry_test7 __ksym;



__u64 test1_result = 0;

SEC("fentry/bpf_fentry_test1")
@@ -71,3 +72,13 @@ int test6(struct pt_regs *ctx) 
	test6_result = (const void *) addr == &bpf_fentry_test6 + 5;

	return 0;

}



__u64 test7_result = 0;

SEC("kprobe/bpf_fentry_test7+5")

int test7(struct pt_regs *ctx)

{

	__u64 addr = bpf_get_func_ip(ctx);



	test7_result = (const void *) addr == &bpf_fentry_test7 + 5;

	return 0;

}