| Message ID | 20250115-riscv-new-regset-v5-2-d0e6ec031a23@coelacanthus.name (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | riscv/ptrace: add new regset to access original a0 register | expand |
On Wed, Jan 15, 2025 at 04:24:59AM +0800, Celeste Liu wrote: > This test checks that orig_a0 and a0 can be modified and accessed > independently. > > Co-developed-by: Quan Zhou <zhouquan@iscas.ac.cn> > Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> > Co-developed-by: Charlie Jenkins <charlie@rivosinc.com> > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> > Reviewed-by: Björn Töpel <bjorn@rivosinc.com> > Signed-off-by: Celeste Liu <uwu@coelacanthus.name> > --- > tools/testing/selftests/riscv/abi/.gitignore | 1 + > tools/testing/selftests/riscv/abi/Makefile | 6 +- > tools/testing/selftests/riscv/abi/ptrace.c | 201 +++++++++++++++++++++++++++ > 3 files changed, 207 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/riscv/abi/.gitignore b/tools/testing/selftests/riscv/abi/.gitignore > index b38358f91c4d2240ae64892871d9ca98bda1ae58..378c605919a3b3d58eec2701eb7af430cfe315d6 100644 > --- a/tools/testing/selftests/riscv/abi/.gitignore > +++ b/tools/testing/selftests/riscv/abi/.gitignore > @@ -1 +1,2 @@ > pointer_masking > +ptrace > diff --git a/tools/testing/selftests/riscv/abi/Makefile b/tools/testing/selftests/riscv/abi/Makefile > index ed82ff9c664e7eb3f760cbab81fb957ff72579c5..359a082c88a401883fb3776b35e4dacf69beaaaa 100644 > --- a/tools/testing/selftests/riscv/abi/Makefile > +++ b/tools/testing/selftests/riscv/abi/Makefile > @@ -1,10 +1,14 @@ > # SPDX-License-Identifier: GPL-2.0 > > CFLAGS += -I$(top_srcdir)/tools/include > +CFLAGS += $(KHDR_INCLUDES) > > -TEST_GEN_PROGS := pointer_masking > +TEST_GEN_PROGS := pointer_masking ptrace > > include ../../lib.mk > > $(OUTPUT)/pointer_masking: pointer_masking.c > $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ > + > +$(OUTPUT)/ptrace: ptrace.c > + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ > diff --git a/tools/testing/selftests/riscv/abi/ptrace.c b/tools/testing/selftests/riscv/abi/ptrace.c > new file mode 100644 > index 0000000000000000000000000000000000000000..f1a0458adccdd040bfaa350e2e8d98b1ef34c0ad > --- /dev/null > +++ b/tools/testing/selftests/riscv/abi/ptrace.c > @@ -0,0 +1,201 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +#include <stdio.h> > +#include <stdlib.h> > +#include <string.h> > +#include <unistd.h> > +#include <fcntl.h> > +#include <signal.h> > +#include <errno.h> > +#include <sys/types.h> > +#include <sys/ptrace.h> > +#include <sys/stat.h> > +#include <sys/user.h> > +#include <sys/wait.h> > +#include <sys/uio.h> > +#include <linux/elf.h> > +#include <linux/unistd.h> > +#include <linux/ptrace.h> > +#include <asm/ptrace.h> > + > +#include "../../kselftest_harness.h" > + > +#ifndef sizeof_field > +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) > +#endif > +#ifndef offsetofend > +#define offsetofend(TYPE, MEMBER) \ > + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) > +#endif I think this is the sixth test to define these. We should copy include/linux/stddef.h into tools/include. We already have tools/include/uapi/linux/stddef.h with __struct_group and __DECLARE_FLEX_ARRAY, so I think it should just work. > + > + > +#define ORIG_A0_MODIFY 0x01 > +#define A0_MODIFY 0x02 > +#define A0_OLD 0xbadbeefbeeff > +#define A0_NEW 0xffeebfeebdab > + > + > +struct a0_regs { > + __s64 orig_a0; > + __u64 a0; > +}; > + > +#define perr_and_exit(fmt, ...) \ > + ({ \ > + char buf[256]; \ > + snprintf(buf, sizeof(buf), "%s:%d:" fmt ": %m\n", \ > + __func__, __LINE__, ##__VA_ARGS__); \ > + ksft_exit_fail_perror(buf); \ > + }) > + > +static void ptrace_test(int opt, struct a0_regs result[]) > +{ > + int status; > + long rc; > + pid_t pid; > + struct user_regs_struct regs; > + struct iovec iov = { > + .iov_base = ®s, > + .iov_len = sizeof(regs), > + }; > + > + unsigned long orig_a0; > + struct iovec a0_iov = { > + .iov_base = &orig_a0, > + .iov_len = sizeof(orig_a0), > + }; > + struct ptrace_syscall_info syscall_info = { > + .op = 0xff, > + }; > + const unsigned int expected_sci_entry_size = > + offsetofend(struct ptrace_syscall_info, entry.args); > + const unsigned int expected_sci_exit_size = > + offsetofend(struct ptrace_syscall_info, exit.is_error); > + > + pid = fork(); > + if (pid == 0) { > + /* Mark oneself being traced */ > + long val = ptrace(PTRACE_TRACEME, 0, 0, 0); > + > + if (val < 0) > + perr_and_exit("failed to request for tracer to trace me: %ld", val); > + > + kill(getpid(), SIGSTOP); > + > + /* Perform chdir syscall that will be intercepted */ > + syscall(__NR_chdir, A0_OLD); > + > + exit(0); > + } > + > + if (pid < 0) > + ksft_exit_fail_perror("failed to fork"); > + > + for (int i = 0; i < 3; i++) { > + if (waitpid(pid, &status, 0) != pid) > + perr_and_exit("failed to wait for the tracee %d", pid); > + if (WIFSTOPPED(status)) { > + switch (WSTOPSIG(status)) { > + case SIGSTOP: > + if (ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACESYSGOOD) < 0) > + perr_and_exit("failed to set PTRACE_O_TRACESYSGOOD"); > + break; > + case SIGTRAP|0x80: > + /* Modify twice so GET_SYSCALL_INFO get modified a0 and orig_a0 */ > + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) > + perr_and_exit("failed to get tracee registers"); > + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) > + perr_and_exit("failed to get tracee registers"); > + > + /* Modify a0/orig_a0 for the syscall */ > + switch (opt) { > + case A0_MODIFY: > + regs.a0 = A0_NEW; > + break; > + case ORIG_A0_MODIFY: > + orig_a0 = A0_NEW; > + break; > + } > + > + if (ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &iov)) > + perr_and_exit("failed to set tracee registers"); > + if (ptrace(PTRACE_SETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) > + perr_and_exit("failed to set tracee registers"); > + switch (i) { > + case 1: > + /* Stop at the beginning of syscall */ > + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, > + sizeof(syscall_info), &syscall_info); > + if (rc < 0) > + perr_and_exit("failed to get syscall info of entry"); > + if (rc < expected_sci_entry_size > + || syscall_info.op != PTRACE_SYSCALL_INFO_ENTRY) > + perr_and_exit("stop position of entry mismatched"); > + result[0].orig_a0 = syscall_info.entry.args[0]; > + break; > + > + case 2: > + /* Stop at the end of syscall */ > + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, > + sizeof(syscall_info), &syscall_info); > + if (rc < 0) > + perr_and_exit("failed to get syscall info of entry"); > + if (rc < expected_sci_exit_size > + || syscall_info.op != PTRACE_SYSCALL_INFO_EXIT) > + perr_and_exit("stop position of exit mismatched"); > + result[0].a0 = syscall_info.exit.rval; > + > + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) > + perr_and_exit("failed to get tracee registers"); > + result[1].a0 = regs.a0; > + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, > + &a0_iov)) > + perr_and_exit("failed to get tracee registers"); > + result[1].orig_a0 = orig_a0; > + } > + } > + if (ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0) > + perr_and_exit("failed to resume tracee"); > + } > + } > + > + /* Resume the tracee */ > + ptrace(PTRACE_CONT, pid, 0, 0); > + if (waitpid(pid, &status, 0) != pid) > + perr_and_exit("failed to wait for the tracee"); > + > +} > + > +TEST(ptrace_access_a0) > +{ > + struct a0_regs result[2]; > + > + ptrace_test(A0_MODIFY, result); > + > + /* Verify PTRACE_SETREGSET */ > + /* The modification of a0 cannot affect the first argument of the syscall */ > + EXPECT_EQ(A0_OLD, result[0].orig_a0); > + EXPECT_EQ(A0_NEW, result[0].a0); > + > + /* Verify PTRACE_GETREGSET */ > + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); > + EXPECT_EQ(result[1].a0, result[0].a0); > +} > + > +TEST(ptrace_access_orig_a0) > +{ > + struct a0_regs result[2]; > + > + ptrace_test(ORIG_A0_MODIFY, result); > + > + /* Verify PTRACE_SETREGSET */ > + /* Only modify orig_a0 to change the first argument of the syscall */ > + EXPECT_EQ(A0_NEW, result[0].orig_a0); > + /* a0 will keep default value, orig_a0 or -ENOSYS, depends on internal. */ > + EXPECT_NE(A0_NEW, result[0].a0); I don't understand this test. Why don't we know what to expect? Also, the comment says orig_a0 is an option for the value, but then we don't expect it to be A0_NEW, even though we expect orig_a0 to be A0_NEW? > + > + /* Verify PTRACE_GETREGSET */ > + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); > + EXPECT_EQ(result[1].a0, result[0].a0); > +} > + > +TEST_HARNESS_MAIN > > -- > 2.48.0 > Other than the two comments/questions, this test looks great. Thanks, drew
On 2025-01-15 17:14, Andrew Jones wrote: > On Wed, Jan 15, 2025 at 04:24:59AM +0800, Celeste Liu wrote: >> This test checks that orig_a0 and a0 can be modified and accessed >> independently. >> >> Co-developed-by: Quan Zhou <zhouquan@iscas.ac.cn> >> Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> >> Co-developed-by: Charlie Jenkins <charlie@rivosinc.com> >> Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> >> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> >> Signed-off-by: Celeste Liu <uwu@coelacanthus.name> >> --- >> tools/testing/selftests/riscv/abi/.gitignore | 1 + >> tools/testing/selftests/riscv/abi/Makefile | 6 +- >> tools/testing/selftests/riscv/abi/ptrace.c | 201 +++++++++++++++++++++++++++ >> 3 files changed, 207 insertions(+), 1 deletion(-) >> >> diff --git a/tools/testing/selftests/riscv/abi/.gitignore b/tools/testing/selftests/riscv/abi/.gitignore >> index b38358f91c4d2240ae64892871d9ca98bda1ae58..378c605919a3b3d58eec2701eb7af430cfe315d6 100644 >> --- a/tools/testing/selftests/riscv/abi/.gitignore >> +++ b/tools/testing/selftests/riscv/abi/.gitignore >> @@ -1 +1,2 @@ >> pointer_masking >> +ptrace >> diff --git a/tools/testing/selftests/riscv/abi/Makefile b/tools/testing/selftests/riscv/abi/Makefile >> index ed82ff9c664e7eb3f760cbab81fb957ff72579c5..359a082c88a401883fb3776b35e4dacf69beaaaa 100644 >> --- a/tools/testing/selftests/riscv/abi/Makefile >> +++ b/tools/testing/selftests/riscv/abi/Makefile >> @@ -1,10 +1,14 @@ >> # SPDX-License-Identifier: GPL-2.0 >> >> CFLAGS += -I$(top_srcdir)/tools/include >> +CFLAGS += $(KHDR_INCLUDES) >> >> -TEST_GEN_PROGS := pointer_masking >> +TEST_GEN_PROGS := pointer_masking ptrace >> >> include ../../lib.mk >> >> $(OUTPUT)/pointer_masking: pointer_masking.c >> $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ >> + >> +$(OUTPUT)/ptrace: ptrace.c >> + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ >> diff --git a/tools/testing/selftests/riscv/abi/ptrace.c b/tools/testing/selftests/riscv/abi/ptrace.c >> new file mode 100644 >> index 0000000000000000000000000000000000000000..f1a0458adccdd040bfaa350e2e8d98b1ef34c0ad >> --- /dev/null >> +++ b/tools/testing/selftests/riscv/abi/ptrace.c >> @@ -0,0 +1,201 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +#include <stdio.h> >> +#include <stdlib.h> >> +#include <string.h> >> +#include <unistd.h> >> +#include <fcntl.h> >> +#include <signal.h> >> +#include <errno.h> >> +#include <sys/types.h> >> +#include <sys/ptrace.h> >> +#include <sys/stat.h> >> +#include <sys/user.h> >> +#include <sys/wait.h> >> +#include <sys/uio.h> >> +#include <linux/elf.h> >> +#include <linux/unistd.h> >> +#include <linux/ptrace.h> >> +#include <asm/ptrace.h> >> + >> +#include "../../kselftest_harness.h" >> + >> +#ifndef sizeof_field >> +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) >> +#endif >> +#ifndef offsetofend >> +#define offsetofend(TYPE, MEMBER) \ >> + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) >> +#endif > > I think this is the sixth test to define these. We should copy > include/linux/stddef.h into tools/include. We already have > tools/include/uapi/linux/stddef.h with __struct_group and > __DECLARE_FLEX_ARRAY, so I think it should just work. Agreed. But it may be better to be a separate patchset so we can change those definition in different selftests one pass. > >> + >> + >> +#define ORIG_A0_MODIFY 0x01 >> +#define A0_MODIFY 0x02 >> +#define A0_OLD 0xbadbeefbeeff >> +#define A0_NEW 0xffeebfeebdab >> + >> + >> +struct a0_regs { >> + __s64 orig_a0; >> + __u64 a0; >> +}; >> + >> +#define perr_and_exit(fmt, ...) \ >> + ({ \ >> + char buf[256]; \ >> + snprintf(buf, sizeof(buf), "%s:%d:" fmt ": %m\n", \ >> + __func__, __LINE__, ##__VA_ARGS__); \ >> + ksft_exit_fail_perror(buf); \ >> + }) >> + >> +static void ptrace_test(int opt, struct a0_regs result[]) >> +{ >> + int status; >> + long rc; >> + pid_t pid; >> + struct user_regs_struct regs; >> + struct iovec iov = { >> + .iov_base = ®s, >> + .iov_len = sizeof(regs), >> + }; >> + >> + unsigned long orig_a0; >> + struct iovec a0_iov = { >> + .iov_base = &orig_a0, >> + .iov_len = sizeof(orig_a0), >> + }; >> + struct ptrace_syscall_info syscall_info = { >> + .op = 0xff, >> + }; >> + const unsigned int expected_sci_entry_size = >> + offsetofend(struct ptrace_syscall_info, entry.args); >> + const unsigned int expected_sci_exit_size = >> + offsetofend(struct ptrace_syscall_info, exit.is_error); >> + >> + pid = fork(); >> + if (pid == 0) { >> + /* Mark oneself being traced */ >> + long val = ptrace(PTRACE_TRACEME, 0, 0, 0); >> + >> + if (val < 0) >> + perr_and_exit("failed to request for tracer to trace me: %ld", val); >> + >> + kill(getpid(), SIGSTOP); >> + >> + /* Perform chdir syscall that will be intercepted */ >> + syscall(__NR_chdir, A0_OLD); >> + >> + exit(0); >> + } >> + >> + if (pid < 0) >> + ksft_exit_fail_perror("failed to fork"); >> + >> + for (int i = 0; i < 3; i++) { >> + if (waitpid(pid, &status, 0) != pid) >> + perr_and_exit("failed to wait for the tracee %d", pid); >> + if (WIFSTOPPED(status)) { >> + switch (WSTOPSIG(status)) { >> + case SIGSTOP: >> + if (ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACESYSGOOD) < 0) >> + perr_and_exit("failed to set PTRACE_O_TRACESYSGOOD"); >> + break; >> + case SIGTRAP|0x80: >> + /* Modify twice so GET_SYSCALL_INFO get modified a0 and orig_a0 */ >> + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) >> + perr_and_exit("failed to get tracee registers"); >> + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) >> + perr_and_exit("failed to get tracee registers"); >> + >> + /* Modify a0/orig_a0 for the syscall */ >> + switch (opt) { >> + case A0_MODIFY: >> + regs.a0 = A0_NEW; >> + break; >> + case ORIG_A0_MODIFY: >> + orig_a0 = A0_NEW; >> + break; >> + } >> + >> + if (ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &iov)) >> + perr_and_exit("failed to set tracee registers"); >> + if (ptrace(PTRACE_SETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) >> + perr_and_exit("failed to set tracee registers"); >> + switch (i) { >> + case 1: >> + /* Stop at the beginning of syscall */ >> + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, >> + sizeof(syscall_info), &syscall_info); >> + if (rc < 0) >> + perr_and_exit("failed to get syscall info of entry"); >> + if (rc < expected_sci_entry_size >> + || syscall_info.op != PTRACE_SYSCALL_INFO_ENTRY) >> + perr_and_exit("stop position of entry mismatched"); >> + result[0].orig_a0 = syscall_info.entry.args[0]; >> + break; >> + >> + case 2: >> + /* Stop at the end of syscall */ >> + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, >> + sizeof(syscall_info), &syscall_info); >> + if (rc < 0) >> + perr_and_exit("failed to get syscall info of entry"); >> + if (rc < expected_sci_exit_size >> + || syscall_info.op != PTRACE_SYSCALL_INFO_EXIT) >> + perr_and_exit("stop position of exit mismatched"); >> + result[0].a0 = syscall_info.exit.rval; >> + >> + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) >> + perr_and_exit("failed to get tracee registers"); >> + result[1].a0 = regs.a0; >> + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, >> + &a0_iov)) >> + perr_and_exit("failed to get tracee registers"); >> + result[1].orig_a0 = orig_a0; >> + } >> + } >> + if (ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0) >> + perr_and_exit("failed to resume tracee"); >> + } >> + } >> + >> + /* Resume the tracee */ >> + ptrace(PTRACE_CONT, pid, 0, 0); >> + if (waitpid(pid, &status, 0) != pid) >> + perr_and_exit("failed to wait for the tracee"); >> + >> +} >> + >> +TEST(ptrace_access_a0) >> +{ >> + struct a0_regs result[2]; >> + >> + ptrace_test(A0_MODIFY, result); >> + >> + /* Verify PTRACE_SETREGSET */ >> + /* The modification of a0 cannot affect the first argument of the syscall */ >> + EXPECT_EQ(A0_OLD, result[0].orig_a0); >> + EXPECT_EQ(A0_NEW, result[0].a0); >> + >> + /* Verify PTRACE_GETREGSET */ >> + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); >> + EXPECT_EQ(result[1].a0, result[0].a0); >> +} >> + >> +TEST(ptrace_access_orig_a0) >> +{ >> + struct a0_regs result[2]; >> + >> + ptrace_test(ORIG_A0_MODIFY, result); >> + >> + /* Verify PTRACE_SETREGSET */ >> + /* Only modify orig_a0 to change the first argument of the syscall */ >> + EXPECT_EQ(A0_NEW, result[0].orig_a0); >> + /* a0 will keep default value, orig_a0 or -ENOSYS, depends on internal. */ >> + EXPECT_NE(A0_NEW, result[0].a0); > > I don't understand this test. Why don't we know what to expect? Also, the > comment says orig_a0 is an option for the value, but then we don't expect > it to be A0_NEW, even though we expect orig_a0 to be A0_NEW? The purpose of the test is to ensure that the ORIG_A0_MODIFY operation will not affect the a0 register (So it will not be our A0_NEW). But there is a problem with the comment. It is written for some old wrong code. I will correct the comment. > >> + >> + /* Verify PTRACE_GETREGSET */ >> + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); >> + EXPECT_EQ(result[1].a0, result[0].a0); >> +} >> + >> +TEST_HARNESS_MAIN >> >> -- >> 2.48.0 >> > > Other than the two comments/questions, this test looks great. > > Thanks, > drew
On Wed, Jan 15, 2025 at 05:41:57PM +0800, Celeste Liu wrote: > On 2025-01-15 17:14, Andrew Jones wrote: > > On Wed, Jan 15, 2025 at 04:24:59AM +0800, Celeste Liu wrote: ... > >> +#ifndef sizeof_field > >> +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) > >> +#endif > >> +#ifndef offsetofend > >> +#define offsetofend(TYPE, MEMBER) \ > >> + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) > >> +#endif > > > > I think this is the sixth test to define these. We should copy > > include/linux/stddef.h into tools/include. We already have > > tools/include/uapi/linux/stddef.h with __struct_group and > > __DECLARE_FLEX_ARRAY, so I think it should just work. > > Agreed. But it may be better to be a separate patchset > so we can change those definition in different selftests > one pass. > I think a separate "copy stddef.h" patch could be in this series to avoid having to add the defines here. Then, another series can be sent with one patch for each conversion. That said, I'm OK with adding the defines for now and doing the conversion later. I just hope it will actually happen. Thanks, drew
On 2025-01-15 17:56, Andrew Jones wrote: > On Wed, Jan 15, 2025 at 05:41:57PM +0800, Celeste Liu wrote: >> On 2025-01-15 17:14, Andrew Jones wrote: >>> On Wed, Jan 15, 2025 at 04:24:59AM +0800, Celeste Liu wrote: > ... >>>> +#ifndef sizeof_field >>>> +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) >>>> +#endif >>>> +#ifndef offsetofend >>>> +#define offsetofend(TYPE, MEMBER) \ >>>> + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) >>>> +#endif >>> >>> I think this is the sixth test to define these. We should copy >>> include/linux/stddef.h into tools/include. We already have >>> tools/include/uapi/linux/stddef.h with __struct_group and >>> __DECLARE_FLEX_ARRAY, so I think it should just work. >> >> Agreed. But it may be better to be a separate patchset >> so we can change those definition in different selftests >> one pass. >> > > I think a separate "copy stddef.h" patch could be in this series to > avoid having to add the defines here. Then, another series can be > sent with one patch for each conversion. That said, I'm OK with > adding the defines for now and doing the conversion later. I just > hope it will actually happen. v6 has been sent. The "copy stddef.h" patch has been included. Once this patchset land, I will send another patchset to deal with other usages. https://lore.kernel.org/lkml/20250115-riscv-new-regset-v6-0-59bfddd33525@coelacanthus.name/T/ > > Thanks, > drew
diff --git a/tools/testing/selftests/riscv/abi/.gitignore b/tools/testing/selftests/riscv/abi/.gitignore index b38358f91c4d2240ae64892871d9ca98bda1ae58..378c605919a3b3d58eec2701eb7af430cfe315d6 100644 --- a/tools/testing/selftests/riscv/abi/.gitignore +++ b/tools/testing/selftests/riscv/abi/.gitignore @@ -1 +1,2 @@ pointer_masking +ptrace diff --git a/tools/testing/selftests/riscv/abi/Makefile b/tools/testing/selftests/riscv/abi/Makefile index ed82ff9c664e7eb3f760cbab81fb957ff72579c5..359a082c88a401883fb3776b35e4dacf69beaaaa 100644 --- a/tools/testing/selftests/riscv/abi/Makefile +++ b/tools/testing/selftests/riscv/abi/Makefile @@ -1,10 +1,14 @@ # SPDX-License-Identifier: GPL-2.0 CFLAGS += -I$(top_srcdir)/tools/include +CFLAGS += $(KHDR_INCLUDES) -TEST_GEN_PROGS := pointer_masking +TEST_GEN_PROGS := pointer_masking ptrace include ../../lib.mk $(OUTPUT)/pointer_masking: pointer_masking.c $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ + +$(OUTPUT)/ptrace: ptrace.c + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ diff --git a/tools/testing/selftests/riscv/abi/ptrace.c b/tools/testing/selftests/riscv/abi/ptrace.c new file mode 100644 index 0000000000000000000000000000000000000000..f1a0458adccdd040bfaa350e2e8d98b1ef34c0ad --- /dev/null +++ b/tools/testing/selftests/riscv/abi/ptrace.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <signal.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/ptrace.h> +#include <sys/stat.h> +#include <sys/user.h> +#include <sys/wait.h> +#include <sys/uio.h> +#include <linux/elf.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <asm/ptrace.h> + +#include "../../kselftest_harness.h" + +#ifndef sizeof_field +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER)) +#endif +#ifndef offsetofend +#define offsetofend(TYPE, MEMBER) \ + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER)) +#endif + + +#define ORIG_A0_MODIFY 0x01 +#define A0_MODIFY 0x02 +#define A0_OLD 0xbadbeefbeeff +#define A0_NEW 0xffeebfeebdab + + +struct a0_regs { + __s64 orig_a0; + __u64 a0; +}; + +#define perr_and_exit(fmt, ...) \ + ({ \ + char buf[256]; \ + snprintf(buf, sizeof(buf), "%s:%d:" fmt ": %m\n", \ + __func__, __LINE__, ##__VA_ARGS__); \ + ksft_exit_fail_perror(buf); \ + }) + +static void ptrace_test(int opt, struct a0_regs result[]) +{ + int status; + long rc; + pid_t pid; + struct user_regs_struct regs; + struct iovec iov = { + .iov_base = ®s, + .iov_len = sizeof(regs), + }; + + unsigned long orig_a0; + struct iovec a0_iov = { + .iov_base = &orig_a0, + .iov_len = sizeof(orig_a0), + }; + struct ptrace_syscall_info syscall_info = { + .op = 0xff, + }; + const unsigned int expected_sci_entry_size = + offsetofend(struct ptrace_syscall_info, entry.args); + const unsigned int expected_sci_exit_size = + offsetofend(struct ptrace_syscall_info, exit.is_error); + + pid = fork(); + if (pid == 0) { + /* Mark oneself being traced */ + long val = ptrace(PTRACE_TRACEME, 0, 0, 0); + + if (val < 0) + perr_and_exit("failed to request for tracer to trace me: %ld", val); + + kill(getpid(), SIGSTOP); + + /* Perform chdir syscall that will be intercepted */ + syscall(__NR_chdir, A0_OLD); + + exit(0); + } + + if (pid < 0) + ksft_exit_fail_perror("failed to fork"); + + for (int i = 0; i < 3; i++) { + if (waitpid(pid, &status, 0) != pid) + perr_and_exit("failed to wait for the tracee %d", pid); + if (WIFSTOPPED(status)) { + switch (WSTOPSIG(status)) { + case SIGSTOP: + if (ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACESYSGOOD) < 0) + perr_and_exit("failed to set PTRACE_O_TRACESYSGOOD"); + break; + case SIGTRAP|0x80: + /* Modify twice so GET_SYSCALL_INFO get modified a0 and orig_a0 */ + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) + perr_and_exit("failed to get tracee registers"); + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) + perr_and_exit("failed to get tracee registers"); + + /* Modify a0/orig_a0 for the syscall */ + switch (opt) { + case A0_MODIFY: + regs.a0 = A0_NEW; + break; + case ORIG_A0_MODIFY: + orig_a0 = A0_NEW; + break; + } + + if (ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &iov)) + perr_and_exit("failed to set tracee registers"); + if (ptrace(PTRACE_SETREGSET, pid, NT_RISCV_ORIG_A0, &a0_iov)) + perr_and_exit("failed to set tracee registers"); + switch (i) { + case 1: + /* Stop at the beginning of syscall */ + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, + sizeof(syscall_info), &syscall_info); + if (rc < 0) + perr_and_exit("failed to get syscall info of entry"); + if (rc < expected_sci_entry_size + || syscall_info.op != PTRACE_SYSCALL_INFO_ENTRY) + perr_and_exit("stop position of entry mismatched"); + result[0].orig_a0 = syscall_info.entry.args[0]; + break; + + case 2: + /* Stop at the end of syscall */ + rc = ptrace(PTRACE_GET_SYSCALL_INFO, pid, + sizeof(syscall_info), &syscall_info); + if (rc < 0) + perr_and_exit("failed to get syscall info of entry"); + if (rc < expected_sci_exit_size + || syscall_info.op != PTRACE_SYSCALL_INFO_EXIT) + perr_and_exit("stop position of exit mismatched"); + result[0].a0 = syscall_info.exit.rval; + + if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &iov)) + perr_and_exit("failed to get tracee registers"); + result[1].a0 = regs.a0; + if (ptrace(PTRACE_GETREGSET, pid, NT_RISCV_ORIG_A0, + &a0_iov)) + perr_and_exit("failed to get tracee registers"); + result[1].orig_a0 = orig_a0; + } + } + if (ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0) + perr_and_exit("failed to resume tracee"); + } + } + + /* Resume the tracee */ + ptrace(PTRACE_CONT, pid, 0, 0); + if (waitpid(pid, &status, 0) != pid) + perr_and_exit("failed to wait for the tracee"); + +} + +TEST(ptrace_access_a0) +{ + struct a0_regs result[2]; + + ptrace_test(A0_MODIFY, result); + + /* Verify PTRACE_SETREGSET */ + /* The modification of a0 cannot affect the first argument of the syscall */ + EXPECT_EQ(A0_OLD, result[0].orig_a0); + EXPECT_EQ(A0_NEW, result[0].a0); + + /* Verify PTRACE_GETREGSET */ + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); + EXPECT_EQ(result[1].a0, result[0].a0); +} + +TEST(ptrace_access_orig_a0) +{ + struct a0_regs result[2]; + + ptrace_test(ORIG_A0_MODIFY, result); + + /* Verify PTRACE_SETREGSET */ + /* Only modify orig_a0 to change the first argument of the syscall */ + EXPECT_EQ(A0_NEW, result[0].orig_a0); + /* a0 will keep default value, orig_a0 or -ENOSYS, depends on internal. */ + EXPECT_NE(A0_NEW, result[0].a0); + + /* Verify PTRACE_GETREGSET */ + EXPECT_EQ(result[1].orig_a0, result[0].orig_a0); + EXPECT_EQ(result[1].a0, result[0].a0); +} + +TEST_HARNESS_MAIN