summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/bpf/prog_tests
diff options
context:
space:
mode:
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests')
-rw-r--r--tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c385
-rw-r--r--tools/testing/selftests/bpf/prog_tests/uretprobe_stack.c186
2 files changed, 571 insertions, 0 deletions
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..bd8c75b620c2
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
@@ -0,0 +1,385 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+
+#ifdef __x86_64__
+
+#include <unistd.h>
+#include <asm/ptrace.h>
+#include <linux/compiler.h>
+#include <linux/stringify.h>
+#include <sys/wait.h>
+#include <sys/syscall.h>
+#include <sys/prctl.h>
+#include <asm/prctl.h>
+#include "uprobe_syscall.skel.h"
+#include "uprobe_syscall_executed.skel.h"
+
+__naked unsigned long uretprobe_regs_trigger(void)
+{
+ asm volatile (
+ "movq $0xdeadbeef, %rax\n"
+ "ret\n"
+ );
+}
+
+__naked void uretprobe_regs(struct pt_regs *before, struct pt_regs *after)
+{
+ asm volatile (
+ "movq %r15, 0(%rdi)\n"
+ "movq %r14, 8(%rdi)\n"
+ "movq %r13, 16(%rdi)\n"
+ "movq %r12, 24(%rdi)\n"
+ "movq %rbp, 32(%rdi)\n"
+ "movq %rbx, 40(%rdi)\n"
+ "movq %r11, 48(%rdi)\n"
+ "movq %r10, 56(%rdi)\n"
+ "movq %r9, 64(%rdi)\n"
+ "movq %r8, 72(%rdi)\n"
+ "movq %rax, 80(%rdi)\n"
+ "movq %rcx, 88(%rdi)\n"
+ "movq %rdx, 96(%rdi)\n"
+ "movq %rsi, 104(%rdi)\n"
+ "movq %rdi, 112(%rdi)\n"
+ "movq $0, 120(%rdi)\n" /* orig_rax */
+ "movq $0, 128(%rdi)\n" /* rip */
+ "movq $0, 136(%rdi)\n" /* cs */
+ "pushf\n"
+ "pop %rax\n"
+ "movq %rax, 144(%rdi)\n" /* eflags */
+ "movq %rsp, 152(%rdi)\n" /* rsp */
+ "movq $0, 160(%rdi)\n" /* ss */
+
+ /* save 2nd argument */
+ "pushq %rsi\n"
+ "call uretprobe_regs_trigger\n"
+
+ /* save return value and load 2nd argument pointer to rax */
+ "pushq %rax\n"
+ "movq 8(%rsp), %rax\n"
+
+ "movq %r15, 0(%rax)\n"
+ "movq %r14, 8(%rax)\n"
+ "movq %r13, 16(%rax)\n"
+ "movq %r12, 24(%rax)\n"
+ "movq %rbp, 32(%rax)\n"
+ "movq %rbx, 40(%rax)\n"
+ "movq %r11, 48(%rax)\n"
+ "movq %r10, 56(%rax)\n"
+ "movq %r9, 64(%rax)\n"
+ "movq %r8, 72(%rax)\n"
+ "movq %rcx, 88(%rax)\n"
+ "movq %rdx, 96(%rax)\n"
+ "movq %rsi, 104(%rax)\n"
+ "movq %rdi, 112(%rax)\n"
+ "movq $0, 120(%rax)\n" /* orig_rax */
+ "movq $0, 128(%rax)\n" /* rip */
+ "movq $0, 136(%rax)\n" /* cs */
+
+ /* restore return value and 2nd argument */
+ "pop %rax\n"
+ "pop %rsi\n"
+
+ "movq %rax, 80(%rsi)\n"
+
+ "pushf\n"
+ "pop %rax\n"
+
+ "movq %rax, 144(%rsi)\n" /* eflags */
+ "movq %rsp, 152(%rsi)\n" /* rsp */
+ "movq $0, 160(%rsi)\n" /* ss */
+ "ret\n"
+);
+}
+
+static void test_uretprobe_regs_equal(void)
+{
+ struct uprobe_syscall *skel = NULL;
+ struct pt_regs before = {}, after = {};
+ unsigned long *pb = (unsigned long *) &before;
+ unsigned long *pa = (unsigned long *) &after;
+ unsigned long *pp;
+ 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;
+
+ uretprobe_regs(&before, &after);
+
+ pp = (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 uretprobe_regs_trigger 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
+ * uretprobe_regs_trigger call
+ */
+ switch (offset) {
+ /*
+ * These values will be different (not set in uretprobe_regs),
+ * 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(pp[i], pa[i], "register prog-after value check"))
+ fprintf(stdout, "failed register offset %u\n", offset);
+ }
+ }
+
+cleanup:
+ uprobe_syscall__destroy(skel);
+}
+
+#define BPF_TESTMOD_UPROBE_TEST_FILE "/sys/kernel/bpf_testmod_uprobe"
+
+static int write_bpf_testmod_uprobe(unsigned long offset)
+{
+ size_t n, ret;
+ char buf[30];
+ int fd;
+
+ n = sprintf(buf, "%lu", offset);
+
+ fd = open(BPF_TESTMOD_UPROBE_TEST_FILE, O_WRONLY);
+ if (fd < 0)
+ return -errno;
+
+ ret = write(fd, buf, n);
+ close(fd);
+ return ret != n ? (int) ret : 0;
+}
+
+static void test_uretprobe_regs_change(void)
+{
+ struct pt_regs before = {}, after = {};
+ unsigned long *pb = (unsigned long *) &before;
+ unsigned long *pa = (unsigned long *) &after;
+ unsigned long cnt = sizeof(before)/sizeof(*pb);
+ unsigned int i, err, offset;
+
+ offset = get_uprobe_offset(uretprobe_regs_trigger);
+
+ err = write_bpf_testmod_uprobe(offset);
+ if (!ASSERT_OK(err, "register_uprobe"))
+ return;
+
+ uretprobe_regs(&before, &after);
+
+ err = write_bpf_testmod_uprobe(0);
+ if (!ASSERT_OK(err, "unregister_uprobe"))
+ return;
+
+ for (i = 0; i < cnt; i++) {
+ unsigned int offset = i * sizeof(unsigned long);
+
+ switch (offset) {
+ case offsetof(struct pt_regs, rax):
+ ASSERT_EQ(pa[i], 0x12345678deadbeef, "rax");
+ break;
+ case offsetof(struct pt_regs, rcx):
+ ASSERT_EQ(pa[i], 0x87654321feebdaed, "rcx");
+ break;
+ case offsetof(struct pt_regs, r11):
+ ASSERT_EQ(pa[i], (__u64) -1, "r11");
+ break;
+ default:
+ if (!ASSERT_EQ(pa[i], pb[i], "register before-after value check"))
+ fprintf(stdout, "failed register offset %u\n", offset);
+ }
+ }
+}
+
+#ifndef __NR_uretprobe
+#define __NR_uretprobe 467
+#endif
+
+__naked unsigned long uretprobe_syscall_call_1(void)
+{
+ /*
+ * Pretend we are uretprobe trampoline to trigger the return
+ * probe invocation in order to verify we get SIGILL.
+ */
+ asm volatile (
+ "pushq %rax\n"
+ "pushq %rcx\n"
+ "pushq %r11\n"
+ "movq $" __stringify(__NR_uretprobe) ", %rax\n"
+ "syscall\n"
+ "popq %r11\n"
+ "popq %rcx\n"
+ "retq\n"
+ );
+}
+
+__naked unsigned long uretprobe_syscall_call(void)
+{
+ asm volatile (
+ "call uretprobe_syscall_call_1\n"
+ "retq\n"
+ );
+}
+
+static void test_uretprobe_syscall_call(void)
+{
+ LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
+ .retprobe = true,
+ );
+ struct uprobe_syscall_executed *skel;
+ int pid, status, err, go[2], c;
+
+ if (ASSERT_OK(pipe(go), "pipe"))
+ return;
+
+ skel = uprobe_syscall_executed__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "uprobe_syscall_executed__open_and_load"))
+ goto cleanup;
+
+ pid = fork();
+ if (!ASSERT_GE(pid, 0, "fork"))
+ goto cleanup;
+
+ /* child */
+ if (pid == 0) {
+ close(go[1]);
+
+ /* wait for parent's kick */
+ err = read(go[0], &c, 1);
+ if (err != 1)
+ exit(-1);
+
+ uretprobe_syscall_call();
+ _exit(0);
+ }
+
+ skel->links.test = bpf_program__attach_uprobe_multi(skel->progs.test, pid,
+ "/proc/self/exe",
+ "uretprobe_syscall_call", &opts);
+ if (!ASSERT_OK_PTR(skel->links.test, "bpf_program__attach_uprobe_multi"))
+ goto cleanup;
+
+ /* kick the child */
+ write(go[1], &c, 1);
+ err = waitpid(pid, &status, 0);
+ ASSERT_EQ(err, pid, "waitpid");
+
+ /* verify the child got killed with SIGILL */
+ ASSERT_EQ(WIFSIGNALED(status), 1, "WIFSIGNALED");
+ ASSERT_EQ(WTERMSIG(status), SIGILL, "WTERMSIG");
+
+ /* verify the uretprobe program wasn't called */
+ ASSERT_EQ(skel->bss->executed, 0, "executed");
+
+cleanup:
+ uprobe_syscall_executed__destroy(skel);
+ close(go[1]);
+ close(go[0]);
+}
+
+/*
+ * Borrowed from tools/testing/selftests/x86/test_shadow_stack.c.
+ *
+ * For use in inline enablement of shadow stack.
+ *
+ * The program can't return from the point where shadow stack gets enabled
+ * because there will be no address on the shadow stack. So it can't use
+ * syscall() for enablement, since it is a function.
+ *
+ * Based on code from nolibc.h. Keep a copy here because this can't pull
+ * in all of nolibc.h.
+ */
+#define ARCH_PRCTL(arg1, arg2) \
+({ \
+ long _ret; \
+ register long _num asm("eax") = __NR_arch_prctl; \
+ register long _arg1 asm("rdi") = (long)(arg1); \
+ register long _arg2 asm("rsi") = (long)(arg2); \
+ \
+ asm volatile ( \
+ "syscall\n" \
+ : "=a"(_ret) \
+ : "r"(_arg1), "r"(_arg2), \
+ "0"(_num) \
+ : "rcx", "r11", "memory", "cc" \
+ ); \
+ _ret; \
+})
+
+#ifndef ARCH_SHSTK_ENABLE
+#define ARCH_SHSTK_ENABLE 0x5001
+#define ARCH_SHSTK_DISABLE 0x5002
+#define ARCH_SHSTK_SHSTK (1ULL << 0)
+#endif
+
+static void test_uretprobe_shadow_stack(void)
+{
+ if (ARCH_PRCTL(ARCH_SHSTK_ENABLE, ARCH_SHSTK_SHSTK)) {
+ test__skip();
+ return;
+ }
+
+ /* Run all of the uretprobe tests. */
+ test_uretprobe_regs_equal();
+ test_uretprobe_regs_change();
+ test_uretprobe_syscall_call();
+
+ ARCH_PRCTL(ARCH_SHSTK_DISABLE, ARCH_SHSTK_SHSTK);
+}
+#else
+static void test_uretprobe_regs_equal(void)
+{
+ test__skip();
+}
+
+static void test_uretprobe_regs_change(void)
+{
+ test__skip();
+}
+
+static void test_uretprobe_syscall_call(void)
+{
+ test__skip();
+}
+
+static void test_uretprobe_shadow_stack(void)
+{
+ test__skip();
+}
+#endif
+
+void test_uprobe_syscall(void)
+{
+ if (test__start_subtest("uretprobe_regs_equal"))
+ test_uretprobe_regs_equal();
+ if (test__start_subtest("uretprobe_regs_change"))
+ test_uretprobe_regs_change();
+ if (test__start_subtest("uretprobe_syscall_call"))
+ test_uretprobe_syscall_call();
+ if (test__start_subtest("uretprobe_shadow_stack"))
+ test_uretprobe_shadow_stack();
+}
diff --git a/tools/testing/selftests/bpf/prog_tests/uretprobe_stack.c b/tools/testing/selftests/bpf/prog_tests/uretprobe_stack.c
new file mode 100644
index 000000000000..6deb8d560ddd
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/uretprobe_stack.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+
+#include <test_progs.h>
+#include "uretprobe_stack.skel.h"
+#include "../sdt.h"
+
+/* We set up target_1() -> target_2() -> target_3() -> target_4() -> USDT()
+ * call chain, each being traced by our BPF program. On entry or return from
+ * each target_*() we are capturing user stack trace and recording it in
+ * global variable, so that user space part of the test can validate it.
+ *
+ * Note, we put each target function into a custom section to get those
+ * __start_XXX/__stop_XXX symbols, generated by linker for us, which allow us
+ * to know address range of those functions
+ */
+__attribute__((section("uprobe__target_4")))
+__weak int target_4(void)
+{
+ STAP_PROBE1(uretprobe_stack, target, 42);
+ return 42;
+}
+
+extern const void *__start_uprobe__target_4;
+extern const void *__stop_uprobe__target_4;
+
+__attribute__((section("uprobe__target_3")))
+__weak int target_3(void)
+{
+ return target_4();
+}
+
+extern const void *__start_uprobe__target_3;
+extern const void *__stop_uprobe__target_3;
+
+__attribute__((section("uprobe__target_2")))
+__weak int target_2(void)
+{
+ return target_3();
+}
+
+extern const void *__start_uprobe__target_2;
+extern const void *__stop_uprobe__target_2;
+
+__attribute__((section("uprobe__target_1")))
+__weak int target_1(int depth)
+{
+ if (depth < 1)
+ return 1 + target_1(depth + 1);
+ else
+ return target_2();
+}
+
+extern const void *__start_uprobe__target_1;
+extern const void *__stop_uprobe__target_1;
+
+extern const void *__start_uretprobe_stack_sec;
+extern const void *__stop_uretprobe_stack_sec;
+
+struct range {
+ long start;
+ long stop;
+};
+
+static struct range targets[] = {
+ {}, /* we want target_1 to map to target[1], so need 1-based indexing */
+ { (long)&__start_uprobe__target_1, (long)&__stop_uprobe__target_1 },
+ { (long)&__start_uprobe__target_2, (long)&__stop_uprobe__target_2 },
+ { (long)&__start_uprobe__target_3, (long)&__stop_uprobe__target_3 },
+ { (long)&__start_uprobe__target_4, (long)&__stop_uprobe__target_4 },
+};
+
+static struct range caller = {
+ (long)&__start_uretprobe_stack_sec,
+ (long)&__stop_uretprobe_stack_sec,
+};
+
+static void validate_stack(__u64 *ips, int stack_len, int cnt, ...)
+{
+ int i, j;
+ va_list args;
+
+ if (!ASSERT_GT(stack_len, 0, "stack_len"))
+ return;
+
+ stack_len /= 8;
+
+ /* check if we have enough entries to satisfy test expectations */
+ if (!ASSERT_GE(stack_len, cnt, "stack_len2"))
+ return;
+
+ if (env.verbosity >= VERBOSE_NORMAL) {
+ printf("caller: %#lx - %#lx\n", caller.start, caller.stop);
+ for (i = 1; i < ARRAY_SIZE(targets); i++)
+ printf("target_%d: %#lx - %#lx\n", i, targets[i].start, targets[i].stop);
+ for (i = 0; i < stack_len; i++) {
+ for (j = 1; j < ARRAY_SIZE(targets); j++) {
+ if (ips[i] >= targets[j].start && ips[i] < targets[j].stop)
+ break;
+ }
+ if (j < ARRAY_SIZE(targets)) { /* found target match */
+ printf("ENTRY #%d: %#lx (in target_%d)\n", i, (long)ips[i], j);
+ } else if (ips[i] >= caller.start && ips[i] < caller.stop) {
+ printf("ENTRY #%d: %#lx (in caller)\n", i, (long)ips[i]);
+ } else {
+ printf("ENTRY #%d: %#lx\n", i, (long)ips[i]);
+ }
+ }
+ }
+
+ va_start(args, cnt);
+
+ for (i = cnt - 1; i >= 0; i--) {
+ /* most recent entry is the deepest target function */
+ const struct range *t = va_arg(args, const struct range *);
+
+ ASSERT_GE(ips[i], t->start, "addr_start");
+ ASSERT_LT(ips[i], t->stop, "addr_stop");
+ }
+
+ va_end(args);
+}
+
+/* __weak prevents inlining */
+__attribute__((section("uretprobe_stack_sec")))
+__weak void test_uretprobe_stack(void)
+{
+ LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
+ struct uretprobe_stack *skel;
+ int err;
+
+ skel = uretprobe_stack__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "skel_open"))
+ return;
+
+ err = uretprobe_stack__attach(skel);
+ if (!ASSERT_OK(err, "skel_attach"))
+ goto cleanup;
+
+ /* trigger */
+ ASSERT_EQ(target_1(0), 42 + 1, "trigger_return");
+
+ /*
+ * Stacks captured on ENTRY uprobes
+ */
+
+ /* (uprobe 1) target_1 in stack trace*/
+ validate_stack(skel->bss->entry_stack1, skel->bss->entry1_len,
+ 2, &caller, &targets[1]);
+ /* (uprobe 1, recursed) */
+ validate_stack(skel->bss->entry_stack1_recur, skel->bss->entry1_recur_len,
+ 3, &caller, &targets[1], &targets[1]);
+ /* (uprobe 2) caller -> target_1 -> target_1 -> target_2 */
+ validate_stack(skel->bss->entry_stack2, skel->bss->entry2_len,
+ 4, &caller, &targets[1], &targets[1], &targets[2]);
+ /* (uprobe 3) */
+ validate_stack(skel->bss->entry_stack3, skel->bss->entry3_len,
+ 5, &caller, &targets[1], &targets[1], &targets[2], &targets[3]);
+ /* (uprobe 4) caller -> target_1 -> target_1 -> target_2 -> target_3 -> target_4 */
+ validate_stack(skel->bss->entry_stack4, skel->bss->entry4_len,
+ 6, &caller, &targets[1], &targets[1], &targets[2], &targets[3], &targets[4]);
+
+ /* (USDT): full caller -> target_1 -> target_1 -> target_2 (uretprobed)
+ * -> target_3 -> target_4 (uretprobes) chain
+ */
+ validate_stack(skel->bss->usdt_stack, skel->bss->usdt_len,
+ 6, &caller, &targets[1], &targets[1], &targets[2], &targets[3], &targets[4]);
+
+ /*
+ * Now stacks captured on the way out in EXIT uprobes
+ */
+
+ /* (uretprobe 4) everything up to target_4, but excluding it */
+ validate_stack(skel->bss->exit_stack4, skel->bss->exit4_len,
+ 5, &caller, &targets[1], &targets[1], &targets[2], &targets[3]);
+ /* we didn't install uretprobes on target_2 and target_3 */
+ /* (uretprobe 1, recur) first target_1 call only */
+ validate_stack(skel->bss->exit_stack1_recur, skel->bss->exit1_recur_len,
+ 2, &caller, &targets[1]);
+ /* (uretprobe 1) just a caller in the stack trace */
+ validate_stack(skel->bss->exit_stack1, skel->bss->exit1_len,
+ 1, &caller);
+
+cleanup:
+ uretprobe_stack__destroy(skel);
+}
generated by cgit v1.2.3-70-g09d2 (git 2.51.1) at 2025-10-26 10:21:55 +0000