Commit 202702e8 authored by Ilya Leoshkevich's avatar Ilya Leoshkevich Committed by Andrii Nakryiko
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selftests/bpf: Attach to fopen()/fclose() in attach_probe 



malloc() and free() may be completely replaced by sanitizers, use
fopen() and fclose() instead.

Signed-off-by: default avatarIlya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-7-iii@linux.ibm.com
parent 907300c7

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

+5 −5
Original line number Diff line number Diff line
@@ -33,8 +33,8 @@ void test_attach_probe(void) 
	struct test_attach_probe* skel;

	ssize_t uprobe_offset, ref_ctr_offset;

	struct bpf_link *uprobe_err_link;

	FILE *devnull;

	bool legacy;

	char *mem;



	/* Check if new-style kprobe/uprobe API is supported.

	 * Kernels that support new FD-based kprobe and uprobe BPF attachment
@@ -147,7 +147,7 @@ void test_attach_probe(void) 
	/* test attach by name for a library function, using the library

	 * as the binary argument. libc.so.6 will be resolved via dlopen()/dlinfo().

	 */

	uprobe_opts.func_name = "malloc";

	uprobe_opts.func_name = "fopen";

	uprobe_opts.retprobe = false;

	skel->links.handle_uprobe_byname2 =

			bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname2,
@@ -157,7 +157,7 @@ void test_attach_probe(void) 
	if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname2, "attach_uprobe_byname2"))

		goto cleanup;



	uprobe_opts.func_name = "free";

	uprobe_opts.func_name = "fclose";

	uprobe_opts.retprobe = true;

	skel->links.handle_uretprobe_byname2 =

			bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe_byname2,
@@ -195,8 +195,8 @@ void test_attach_probe(void) 
	usleep(1);



	/* trigger & validate shared library u[ret]probes attached by name */

	mem = malloc(1);

	free(mem);

	devnull = fopen("/dev/null", "r");

	fclose(devnull);



	/* trigger & validate uprobe & uretprobe */

	trigger_func();

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

+6 −5
Original line number Diff line number Diff line
@@ -92,18 +92,19 @@ int handle_uretprobe_byname(struct pt_regs *ctx) 
}



SEC("uprobe")

int handle_uprobe_byname2(struct pt_regs *ctx)

int BPF_UPROBE(handle_uprobe_byname2, const char *pathname, const char *mode)

{

	unsigned int size = PT_REGS_PARM1(ctx);

	char mode_buf[2] = {};



	/* verify malloc size */

	if (size == 1)

	/* verify fopen mode */

	bpf_probe_read_user(mode_buf, sizeof(mode_buf), mode);

	if (mode_buf[0] == 'r' && mode_buf[1] == 0)

		uprobe_byname2_res = 7;

	return 0;

}



SEC("uretprobe")

int handle_uretprobe_byname2(struct pt_regs *ctx)

int BPF_URETPROBE(handle_uretprobe_byname2, void *ret)

{

	uretprobe_byname2_res = 8;

	return 0;