Add uretprobe syscall test and compare register values before
and after the uretprobe is hit. Also compare the register values
seen from attached bpf program.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/testing/selftests/bpf/Makefile | 13 ++-
.../bpf/prog_tests/arch/x86/uprobe_syscall.S | 89 +++++++++++++++++++
.../selftests/bpf/prog_tests/uprobe_syscall.c | 84 +++++++++++++++++
.../selftests/bpf/progs/uprobe_syscall.c | 15 ++++
4 files changed, 200 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/arch/x86/uprobe_syscall.S
create mode 100644 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 3b9eb40d6343..e425a946276b 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -490,6 +490,9 @@ TRUNNER_TEST_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.test.o, \
$$(notdir $$(wildcard $(TRUNNER_TESTS_DIR)/*.c)))
TRUNNER_EXTRA_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o, \
$$(filter %.c,$(TRUNNER_EXTRA_SOURCES)))
+TRUNNER_ASM_OBJS := $$(patsubst %.S,$$(TRUNNER_OUTPUT)/%.arch.o, \
+ $$(notdir $$(wildcard $(TRUNNER_TESTS_DIR)/arch/$(SRCARCH)/*.S)))
+
TRUNNER_EXTRA_HDRS := $$(filter %.h,$(TRUNNER_EXTRA_SOURCES))
TRUNNER_TESTS_HDR := $(TRUNNER_TESTS_DIR)/tests.h
TRUNNER_BPF_SRCS := $$(notdir $$(wildcard $(TRUNNER_BPF_PROGS_DIR)/*.c))
@@ -597,6 +600,13 @@ $(TRUNNER_EXTRA_OBJS): $(TRUNNER_OUTPUT)/%.o: \
$$(call msg,EXT-OBJ,$(TRUNNER_BINARY),$$@)
$(Q)$$(CC) $$(CFLAGS) -c $$< $$(LDLIBS) -o $$@
+$(TRUNNER_ASM_OBJS): $(TRUNNER_OUTPUT)/%.arch.o: \
+ $(TRUNNER_TESTS_DIR)/arch/$(SRCARCH)/%.S \
+ $(TRUNNER_TESTS_HDR) \
+ $$(BPFOBJ) | $(TRUNNER_OUTPUT)
+ $$(call msg,ASM-OBJ,$(TRUNNER_BINARY),$$@)
+ $(Q)$$(CC) $$(CFLAGS) -c $$< $$(LDLIBS) -o $$@
+
# non-flavored in-srctree builds receive special treatment, in particular, we
# do not need to copy extra resources (see e.g. test_btf_dump_case())
$(TRUNNER_BINARY)-extras: $(TRUNNER_EXTRA_FILES) | $(TRUNNER_OUTPUT)
@@ -606,7 +616,8 @@ ifneq ($2:$(OUTPUT),:$(shell pwd))
endif
$(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS) \
- $(TRUNNER_EXTRA_OBJS) $$(BPFOBJ) \
+ $(TRUNNER_EXTRA_OBJS) $(TRUNNER_ASM_OBJS) \
+ $$(BPFOBJ) \
$(RESOLVE_BTFIDS) \
$(TRUNNER_BPFTOOL) \
| $(TRUNNER_BINARY)-extras
diff --git a/tools/testing/selftests/bpf/prog_tests/arch/x86/uprobe_syscall.S b/tools/testing/selftests/bpf/prog_tests/arch/x86/uprobe_syscall.S
new file mode 100644
index 000000000000..bcbad218c4d6
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/arch/x86/uprobe_syscall.S
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef ASM_NL
+#define ASM_NL ;
+#endif
+
+#define SYM_ENTRY(name) \
+ .globl name ASM_NL \
+ name:
+
+#define SYM_END(name) \
+ .type name STT_FUNC ASM_NL \
+ .size name, .-name ASM_NL
+
+.code64
+.section .text, "ax"
+
+SYM_ENTRY(uprobe_syscall_arch_test)
+ movq $0xdeadbeef, %rax
+ ret
+SYM_END(uprobe_syscall_arch_test)
+
+.globl uprobe_syscall_arch
+uprobe_syscall_arch:
+ movq %r15, 0(%rdi)
+ movq %r14, 8(%rdi)
+ movq %r13, 16(%rdi)
+ movq %r12, 24(%rdi)
+ movq %rbp, 32(%rdi)
+ movq %rbx, 40(%rdi)
+ movq %r11, 48(%rdi)
+ movq %r10, 56(%rdi)
+ movq %r9, 64(%rdi)
+ movq %r8, 72(%rdi)
+ movq %rax, 80(%rdi)
+ movq %rcx, 88(%rdi)
+ movq %rdx, 96(%rdi)
+ movq %rsi, 104(%rdi)
+ movq %rdi, 112(%rdi)
+ movq $0, 120(%rdi) /* orig_rax */
+ movq $0, 128(%rdi) /* rip */
+ movq $0, 136(%rdi) /* cs */
+
+ pushf
+ pop %rax
+
+ movq %rax, 144(%rdi) /* eflags */
+ movq %rsp, 152(%rdi) /* rsp */
+ movq $0, 160(%rdi) /* ss */
+
+ pushq %rsi
+ call uprobe_syscall_arch_test
+
+ /* store return value and get second argument pointer to rax */
+ pushq %rax
+ movq 8(%rsp), %rax
+
+ movq %r15, 0(%rax)
+ movq %r14, 8(%rax)
+ movq %r13, 16(%rax)
+ movq %r12, 24(%rax)
+ movq %rbp, 32(%rax)
+ movq %rbx, 40(%rax)
+ movq %r11, 48(%rax)
+ movq %r10, 56(%rax)
+ movq %r9, 64(%rax)
+ movq %r8, 72(%rax)
+ movq %rcx, 88(%rax)
+ movq %rdx, 96(%rax)
+ movq %rsi, 104(%rax)
+ movq %rdi, 112(%rax)
+ movq $0, 120(%rax) /* orig_rax */
+ movq $0, 128(%rax) /* rip */
+ movq $0, 136(%rax) /* cs */
+
+ pop %rax
+ pop %rsi
+ movq %rax, 80(%rsi)
+
+ pushf
+ pop %rax
+
+ movq %rax, 144(%rsi) /* eflags */
+ movq %rsp, 152(%rsi) /* rsp */
+ movq $0, 160(%rsi) /* ss */
+
+ ret
+
+.section .note.GNU-stack,"",@progbits
diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
new file mode 100644
index 000000000000..0df205fea957
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+
+#ifdef __x86_64__
+
+#include <unistd.h>
+#include <asm/ptrace.h>
+#include "uprobe_syscall.skel.h"
+
+extern int uprobe_syscall_arch(struct pt_regs *before, struct pt_regs *after);
+
+static void test_uretprobe(void)
+{
+ struct pt_regs before = {}, after = {};
+ unsigned long *pb = (unsigned long *) &before;
+ unsigned long *pa = (unsigned long *) &after;
+ unsigned long *prog_regs;
+ struct uprobe_syscall *skel = NULL;
+ unsigned int i, cnt;
+ int err;
+
+ skel = uprobe_syscall__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "uprobe_syscall__open_and_load"))
+ goto cleanup;
+
+ err = uprobe_syscall__attach(skel);
+ if (!ASSERT_OK(err, "uprobe_syscall__attach"))
+ goto cleanup;
+
+ uprobe_syscall_arch(&before, &after);
+
+ prog_regs = (unsigned long *) &skel->bss->regs;
+ cnt = sizeof(before)/sizeof(*pb);
+
+ for (i = 0; i < cnt; i++) {
+ unsigned int offset = i * sizeof(unsigned long);
+
+ /*
+ * Check register before and after uprobe_syscall_arch_test call
+ * that triggers the uretprobe.
+ */
+ switch (offset) {
+ case offsetof(struct pt_regs, rax):
+ ASSERT_EQ(pa[i], 0xdeadbeef, "return value");
+ break;
+ default:
+ if (!ASSERT_EQ(pb[i], pa[i], "register before-after value check"))
+ fprintf(stdout, "failed register offset %u\n", offset);
+ }
+
+ /*
+ * Check register seen from bpf program and register after
+ * uprobe_syscall_arch_test call
+ */
+ switch (offset) {
+ /*
+ * These will be different (not set in uprobe_syscall_arch),
+ * we don't care.
+ */
+ case offsetof(struct pt_regs, orig_rax):
+ case offsetof(struct pt_regs, rip):
+ case offsetof(struct pt_regs, cs):
+ case offsetof(struct pt_regs, rsp):
+ case offsetof(struct pt_regs, ss):
+ break;
+ default:
+ if (!ASSERT_EQ(prog_regs[i], pa[i], "register prog-after value check"))
+ fprintf(stdout, "failed register offset %u\n", offset);
+ }
+ }
+
+cleanup:
+ uprobe_syscall__destroy(skel);
+}
+#else
+static void test_uretprobe(void) { }
+#endif
+
+void test_uprobe_syscall(void)
+{
+ if (test__start_subtest("uretprobe"))
+ test_uretprobe();
+}
diff --git a/tools/testing/selftests/bpf/progs/uprobe_syscall.c b/tools/testing/selftests/bpf/progs/uprobe_syscall.c
new file mode 100644
index 000000000000..0cc7e8761410
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/uprobe_syscall.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <string.h>
+
+struct pt_regs regs;
+
+char _license[] SEC("license") = "GPL";
+
+SEC("uretprobe//proc/self/exe:uprobe_syscall_arch_test")
+int uretprobe(struct pt_regs *ctx)
+{
+ memcpy(®s, ctx, sizeof(regs));
+ return 0;
+}
--
2.44.0
