Message ID | 20240507105321.71524-8-jolsa@kernel.org (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | Masami Hiramatsu |
Headers | show |
Series | uprobe: uretprobe speed up | expand |
On Tue, 7 May 2024 12:53:20 +0200 Jiri Olsa <jolsa@kernel.org> wrote: > Adding return uprobe test for shadow stack and making sure it's > working properly. Borrowed some of the code from bpf selftests. Hi Jiri, I can not find "SKIP" result in this change. If CONFIG_UPROBES=n, this should skip uprobe test. Thank you, > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > --- > .../testing/selftests/x86/test_shadow_stack.c | 142 ++++++++++++++++++ > 1 file changed, 142 insertions(+) > > diff --git a/tools/testing/selftests/x86/test_shadow_stack.c b/tools/testing/selftests/x86/test_shadow_stack.c > index 757e6527f67e..1b919baa999b 100644 > --- a/tools/testing/selftests/x86/test_shadow_stack.c > +++ b/tools/testing/selftests/x86/test_shadow_stack.c > @@ -34,6 +34,7 @@ > #include <sys/ptrace.h> > #include <sys/signal.h> > #include <linux/elf.h> > +#include <linux/perf_event.h> > > /* > * Define the ABI defines if needed, so people can run the tests > @@ -681,6 +682,141 @@ int test_32bit(void) > return !segv_triggered; > } > > +static int parse_uint_from_file(const char *file, const char *fmt) > +{ > + int err, ret; > + FILE *f; > + > + f = fopen(file, "re"); > + if (!f) { > + err = -errno; > + printf("failed to open '%s': %d\n", file, err); > + return err; > + } > + err = fscanf(f, fmt, &ret); > + if (err != 1) { > + err = err == EOF ? -EIO : -errno; > + printf("failed to parse '%s': %d\n", file, err); > + fclose(f); > + return err; > + } > + fclose(f); > + return ret; > +} > + > +static int determine_uprobe_perf_type(void) > +{ > + const char *file = "/sys/bus/event_source/devices/uprobe/type"; > + > + return parse_uint_from_file(file, "%d\n"); > +} > + > +static int determine_uprobe_retprobe_bit(void) > +{ > + const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; > + > + return parse_uint_from_file(file, "config:%d\n"); > +} > + > +static ssize_t get_uprobe_offset(const void *addr) > +{ > + size_t start, end, base; > + char buf[256]; > + bool found = false; > + FILE *f; > + > + f = fopen("/proc/self/maps", "r"); > + if (!f) > + return -errno; > + > + while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) { > + if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) { > + found = true; > + break; > + } > + } > + > + fclose(f); > + > + if (!found) > + return -ESRCH; > + > + return (uintptr_t)addr - start + base; > +} > + > +static __attribute__((noinline)) void uretprobe_trigger(void) > +{ > + asm volatile (""); > +} > + > +/* > + * This test setups return uprobe, which is sensitive to shadow stack > + * (crashes without extra fix). After executing the uretprobe we fail > + * the test if we receive SIGSEGV, no crash means we're good. > + * > + * Helper functions above borrowed from bpf selftests. > + */ > +static int test_uretprobe(void) > +{ > + const size_t attr_sz = sizeof(struct perf_event_attr); > + const char *file = "/proc/self/exe"; > + int bit, fd = 0, type, err = 1; > + struct perf_event_attr attr; > + struct sigaction sa = {}; > + ssize_t offset; > + > + type = determine_uprobe_perf_type(); > + if (type < 0) > + return 1; > + > + offset = get_uprobe_offset(uretprobe_trigger); > + if (offset < 0) > + return 1; > + > + bit = determine_uprobe_retprobe_bit(); > + if (bit < 0) > + return 1; > + > + sa.sa_sigaction = segv_gp_handler; > + sa.sa_flags = SA_SIGINFO; > + if (sigaction(SIGSEGV, &sa, NULL)) > + return 1; > + > + /* Setup return uprobe through perf event interface. */ > + memset(&attr, 0, attr_sz); > + attr.size = attr_sz; > + attr.type = type; > + attr.config = 1 << bit; > + attr.config1 = (__u64) (unsigned long) file; > + attr.config2 = offset; > + > + fd = syscall(__NR_perf_event_open, &attr, 0 /* pid */, -1 /* cpu */, > + -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); > + if (fd < 0) > + goto out; > + > + if (sigsetjmp(jmp_buffer, 1)) > + goto out; > + > + ARCH_PRCTL(ARCH_SHSTK_ENABLE, ARCH_SHSTK_SHSTK); > + > + /* > + * This either segfaults and goes through sigsetjmp above > + * or succeeds and we're good. > + */ > + uretprobe_trigger(); > + > + printf("[OK]\tUretprobe test\n"); > + err = 0; > + > +out: > + ARCH_PRCTL(ARCH_SHSTK_DISABLE, ARCH_SHSTK_SHSTK); > + signal(SIGSEGV, SIG_DFL); > + if (fd) > + close(fd); > + return err; > +} > + > void segv_handler_ptrace(int signum, siginfo_t *si, void *uc) > { > /* The SSP adjustment caused a segfault. */ > @@ -867,6 +1003,12 @@ int main(int argc, char *argv[]) > goto out; > } > > + if (test_uretprobe()) { > + ret = 1; > + printf("[FAIL]\turetprobe test\n"); > + goto out; > + } > + > return ret; > > out: > -- > 2.44.0 >
On Mon, May 13, 2024 at 06:45:07PM +0900, Masami Hiramatsu wrote: > On Tue, 7 May 2024 12:53:20 +0200 > Jiri Olsa <jolsa@kernel.org> wrote: > > > Adding return uprobe test for shadow stack and making sure it's > > working properly. Borrowed some of the code from bpf selftests. > > Hi Jiri, > > I can not find "SKIP" result in this change. If CONFIG_UPROBES=n, > this should skip uprobe test. ah it should be detected by parse_uint_from_file returning ENOENT or something like that.. will add that thanks, jirka > > Thank you, > > > > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > > --- > > .../testing/selftests/x86/test_shadow_stack.c | 142 ++++++++++++++++++ > > 1 file changed, 142 insertions(+) > > > > diff --git a/tools/testing/selftests/x86/test_shadow_stack.c b/tools/testing/selftests/x86/test_shadow_stack.c > > index 757e6527f67e..1b919baa999b 100644 > > --- a/tools/testing/selftests/x86/test_shadow_stack.c > > +++ b/tools/testing/selftests/x86/test_shadow_stack.c > > @@ -34,6 +34,7 @@ > > #include <sys/ptrace.h> > > #include <sys/signal.h> > > #include <linux/elf.h> > > +#include <linux/perf_event.h> > > > > /* > > * Define the ABI defines if needed, so people can run the tests > > @@ -681,6 +682,141 @@ int test_32bit(void) > > return !segv_triggered; > > } > > > > +static int parse_uint_from_file(const char *file, const char *fmt) > > +{ > > + int err, ret; > > + FILE *f; > > + > > + f = fopen(file, "re"); > > + if (!f) { > > + err = -errno; > > + printf("failed to open '%s': %d\n", file, err); > > + return err; > > + } > > + err = fscanf(f, fmt, &ret); > > + if (err != 1) { > > + err = err == EOF ? -EIO : -errno; > > + printf("failed to parse '%s': %d\n", file, err); > > + fclose(f); > > + return err; > > + } > > + fclose(f); > > + return ret; > > +} > > + > > +static int determine_uprobe_perf_type(void) > > +{ > > + const char *file = "/sys/bus/event_source/devices/uprobe/type"; > > + > > + return parse_uint_from_file(file, "%d\n"); > > +} > > + > > +static int determine_uprobe_retprobe_bit(void) > > +{ > > + const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; > > + > > + return parse_uint_from_file(file, "config:%d\n"); > > +} > > + > > +static ssize_t get_uprobe_offset(const void *addr) > > +{ > > + size_t start, end, base; > > + char buf[256]; > > + bool found = false; > > + FILE *f; > > + > > + f = fopen("/proc/self/maps", "r"); > > + if (!f) > > + return -errno; > > + > > + while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) { > > + if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) { > > + found = true; > > + break; > > + } > > + } > > + > > + fclose(f); > > + > > + if (!found) > > + return -ESRCH; > > + > > + return (uintptr_t)addr - start + base; > > +} > > + > > +static __attribute__((noinline)) void uretprobe_trigger(void) > > +{ > > + asm volatile (""); > > +} > > + > > +/* > > + * This test setups return uprobe, which is sensitive to shadow stack > > + * (crashes without extra fix). After executing the uretprobe we fail > > + * the test if we receive SIGSEGV, no crash means we're good. > > + * > > + * Helper functions above borrowed from bpf selftests. > > + */ > > +static int test_uretprobe(void) > > +{ > > + const size_t attr_sz = sizeof(struct perf_event_attr); > > + const char *file = "/proc/self/exe"; > > + int bit, fd = 0, type, err = 1; > > + struct perf_event_attr attr; > > + struct sigaction sa = {}; > > + ssize_t offset; > > + > > + type = determine_uprobe_perf_type(); > > + if (type < 0) > > + return 1; > > + > > + offset = get_uprobe_offset(uretprobe_trigger); > > + if (offset < 0) > > + return 1; > > + > > + bit = determine_uprobe_retprobe_bit(); > > + if (bit < 0) > > + return 1; > > + > > + sa.sa_sigaction = segv_gp_handler; > > + sa.sa_flags = SA_SIGINFO; > > + if (sigaction(SIGSEGV, &sa, NULL)) > > + return 1; > > + > > + /* Setup return uprobe through perf event interface. */ > > + memset(&attr, 0, attr_sz); > > + attr.size = attr_sz; > > + attr.type = type; > > + attr.config = 1 << bit; > > + attr.config1 = (__u64) (unsigned long) file; > > + attr.config2 = offset; > > + > > + fd = syscall(__NR_perf_event_open, &attr, 0 /* pid */, -1 /* cpu */, > > + -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); > > + if (fd < 0) > > + goto out; > > + > > + if (sigsetjmp(jmp_buffer, 1)) > > + goto out; > > + > > + ARCH_PRCTL(ARCH_SHSTK_ENABLE, ARCH_SHSTK_SHSTK); > > + > > + /* > > + * This either segfaults and goes through sigsetjmp above > > + * or succeeds and we're good. > > + */ > > + uretprobe_trigger(); > > + > > + printf("[OK]\tUretprobe test\n"); > > + err = 0; > > + > > +out: > > + ARCH_PRCTL(ARCH_SHSTK_DISABLE, ARCH_SHSTK_SHSTK); > > + signal(SIGSEGV, SIG_DFL); > > + if (fd) > > + close(fd); > > + return err; > > +} > > + > > void segv_handler_ptrace(int signum, siginfo_t *si, void *uc) > > { > > /* The SSP adjustment caused a segfault. */ > > @@ -867,6 +1003,12 @@ int main(int argc, char *argv[]) > > goto out; > > } > > > > + if (test_uretprobe()) { > > + ret = 1; > > + printf("[FAIL]\turetprobe test\n"); > > + goto out; > > + } > > + > > return ret; > > > > out: > > -- > > 2.44.0 > > > > > -- > Masami Hiramatsu (Google) <mhiramat@kernel.org>
diff --git a/tools/testing/selftests/x86/test_shadow_stack.c b/tools/testing/selftests/x86/test_shadow_stack.c index 757e6527f67e..1b919baa999b 100644 --- a/tools/testing/selftests/x86/test_shadow_stack.c +++ b/tools/testing/selftests/x86/test_shadow_stack.c @@ -34,6 +34,7 @@ #include <sys/ptrace.h> #include <sys/signal.h> #include <linux/elf.h> +#include <linux/perf_event.h> /* * Define the ABI defines if needed, so people can run the tests @@ -681,6 +682,141 @@ int test_32bit(void) return !segv_triggered; } +static int parse_uint_from_file(const char *file, const char *fmt) +{ + int err, ret; + FILE *f; + + f = fopen(file, "re"); + if (!f) { + err = -errno; + printf("failed to open '%s': %d\n", file, err); + return err; + } + err = fscanf(f, fmt, &ret); + if (err != 1) { + err = err == EOF ? -EIO : -errno; + printf("failed to parse '%s': %d\n", file, err); + fclose(f); + return err; + } + fclose(f); + return ret; +} + +static int determine_uprobe_perf_type(void) +{ + const char *file = "/sys/bus/event_source/devices/uprobe/type"; + + return parse_uint_from_file(file, "%d\n"); +} + +static int determine_uprobe_retprobe_bit(void) +{ + const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; + + return parse_uint_from_file(file, "config:%d\n"); +} + +static ssize_t get_uprobe_offset(const void *addr) +{ + size_t start, end, base; + char buf[256]; + bool found = false; + FILE *f; + + f = fopen("/proc/self/maps", "r"); + if (!f) + return -errno; + + while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) { + if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) { + found = true; + break; + } + } + + fclose(f); + + if (!found) + return -ESRCH; + + return (uintptr_t)addr - start + base; +} + +static __attribute__((noinline)) void uretprobe_trigger(void) +{ + asm volatile (""); +} + +/* + * This test setups return uprobe, which is sensitive to shadow stack + * (crashes without extra fix). After executing the uretprobe we fail + * the test if we receive SIGSEGV, no crash means we're good. + * + * Helper functions above borrowed from bpf selftests. + */ +static int test_uretprobe(void) +{ + const size_t attr_sz = sizeof(struct perf_event_attr); + const char *file = "/proc/self/exe"; + int bit, fd = 0, type, err = 1; + struct perf_event_attr attr; + struct sigaction sa = {}; + ssize_t offset; + + type = determine_uprobe_perf_type(); + if (type < 0) + return 1; + + offset = get_uprobe_offset(uretprobe_trigger); + if (offset < 0) + return 1; + + bit = determine_uprobe_retprobe_bit(); + if (bit < 0) + return 1; + + sa.sa_sigaction = segv_gp_handler; + sa.sa_flags = SA_SIGINFO; + if (sigaction(SIGSEGV, &sa, NULL)) + return 1; + + /* Setup return uprobe through perf event interface. */ + memset(&attr, 0, attr_sz); + attr.size = attr_sz; + attr.type = type; + attr.config = 1 << bit; + attr.config1 = (__u64) (unsigned long) file; + attr.config2 = offset; + + fd = syscall(__NR_perf_event_open, &attr, 0 /* pid */, -1 /* cpu */, + -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); + if (fd < 0) + goto out; + + if (sigsetjmp(jmp_buffer, 1)) + goto out; + + ARCH_PRCTL(ARCH_SHSTK_ENABLE, ARCH_SHSTK_SHSTK); + + /* + * This either segfaults and goes through sigsetjmp above + * or succeeds and we're good. + */ + uretprobe_trigger(); + + printf("[OK]\tUretprobe test\n"); + err = 0; + +out: + ARCH_PRCTL(ARCH_SHSTK_DISABLE, ARCH_SHSTK_SHSTK); + signal(SIGSEGV, SIG_DFL); + if (fd) + close(fd); + return err; +} + void segv_handler_ptrace(int signum, siginfo_t *si, void *uc) { /* The SSP adjustment caused a segfault. */ @@ -867,6 +1003,12 @@ int main(int argc, char *argv[]) goto out; } + if (test_uretprobe()) { + ret = 1; + printf("[FAIL]\turetprobe test\n"); + goto out; + } + return ret; out:
Adding return uprobe test for shadow stack and making sure it's working properly. Borrowed some of the code from bpf selftests. Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- .../testing/selftests/x86/test_shadow_stack.c | 142 ++++++++++++++++++ 1 file changed, 142 insertions(+)