Re: [PATCH 09/14] add syscall tests

[Samuel Thibault]

Luca Dariz, le jeu. 28 déc. 2023 20:42:56 +0100, a ecrit:
> ---
>  tests/test-syscalls.c | 149 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 149 insertions(+)
>  create mode 100644 tests/test-syscalls.c
> 
> diff --git a/tests/test-syscalls.c b/tests/test-syscalls.c
> new file mode 100644
> index 00000000..7e4234ac
> --- /dev/null
> +++ b/tests/test-syscalls.c
> @@ -0,0 +1,149 @@
> +
> +#include <syscalls.h>
> +#include <testlib.h>
> +
> +#include <mach/exception.h>
> +#include <mach/mig_errors.h>
> +#include <mach/vm_param.h>
> +
> +#include <mach.user.h>
> +#include <mach_port.user.h>
> +#include <exc.server.h>
> +
> +
> +static struct {
> +  mach_port_t exception_port;
> +  mach_port_t thread;
> +  mach_port_t task;
> +  integer_t exception;
> +  integer_t code;
> +  integer_t subcode;
> +} last_exc;
> +kern_return_t catch_exception_raise(mach_port_t exception_port,
> +                                    mach_port_t thread, mach_port_t task,
> +                                    integer_t exception, integer_t code,
> +                                    long_integer_t subcode)
> +{
> +  printf("received catch_exception_raise(%u %u %u %d %d %d)\n",
> +         exception_port, thread, task, exception, code, subcode);
> +  last_exc.exception_port = exception_port;
> +  last_exc.thread = thread;
> +  last_exc.task = task;
> +  last_exc.exception = exception;
> +  last_exc.code = code;
> +  last_exc.subcode = subcode;
> +  return KERN_SUCCESS;
> +}
> +
> +static char simple_request_data[PAGE_SIZE];
> +static char simple_reply_data[PAGE_SIZE];
> +int simple_msg_server(boolean_t (*demuxer) (mach_msg_header_t *request,
> +                                             mach_msg_header_t *reply),
> +                      mach_port_t rcv_port_name,
> +                      int num_msgs)
> +{
> +  int midx = 0, mok = 0;
> +  int ret;
> +  mig_reply_header_t *request = (mig_reply_header_t*)simple_request_data;
> +  mig_reply_header_t *reply = (mig_reply_header_t*)simple_reply_data;
> +  while ((midx - num_msgs) < 0)
> +    {
> +      ret = mach_msg(&request->Head, MACH_RCV_MSG, 0, PAGE_SIZE,
> +                     rcv_port_name, 0, MACH_PORT_NULL);
> +      switch (ret)
> +        {
> +        case MACH_MSG_SUCCESS:
> +          if ((*demuxer)(&request->Head, &reply->Head))
> +            mok++;  // TODO send reply
> +          else
> +            FAILURE("demuxer didn't handle the message");
> +          break;
> +        default:
> +          ASSERT_RET(ret, "receiving in msg_server");
> +          break;
> +        }
> +      midx++;
> +    }
> +  if (mok != midx)
> +    FAILURE("wrong number of message received");
> +  return mok != midx;
> +}
> +
> +
> +void test_syscall_bad_arg_on_stack(void *arg)
> +{
> +  /* mach_msg() has 7 arguments, so the last one should be passed on the 
> stack
> +     make RSP points the the wrong place to check the access check

"the the" typo

> +  */
> +#ifdef __x86_64__
> +  asm volatile("movq $0x123,%rsp;"                   \
> +               "movq $-25,%rax;"                     \
> +               "syscall;"                               \
> +               );
> +#else
> +  asm volatile("mov  $0x123,%esp;"                   \
> +               "mov  $-25,%eax;"                     \
> +               "lcall        $0x7,$0x0;"                     \
> +               );
> +#endif
> +  FAILURE("we shouldn't be here!");
> +}
> +
> +void test_bad_syscall_num(void *arg)
> +{
> +#ifdef __x86_64__
> +  asm volatile("movq $0x123456,%rax;"                \
> +               "syscall;"                               \
> +               );
> +#else
> +  asm volatile("mov  $0x123456,%eax;"                \
> +               "lcall        $0x7,$0x0;"                     \
> +               );
> +#endif
> +  FAILURE("we shouldn't be here!");
> +}
> +
> +
> +int main(int argc, char *argv[], int envc, char *envp[])
> +{
> +  int err;
> +  mach_port_t excp;
> +
> +  err = mach_port_allocate(mach_task_self (), MACH_PORT_RIGHT_RECEIVE, 
> &excp);
> +  ASSERT_RET(err, "creating exception port");
> +
> +  err = mach_port_insert_right(mach_task_self(), excp, excp,
> +                               MACH_MSG_TYPE_MAKE_SEND);
> +  ASSERT_RET(err, "inserting sr into exception port");
> +
> +  err = task_set_special_port(mach_task_self(), TASK_EXCEPTION_PORT, excp);
> +  ASSERT_RET(err, "setting task exception port");
> +
> +  /* FIXME: receiving an exception with small size causes GP on 64 bit 
> userspace */
> +  /* mig_reply_header_t msg; */
> +  /* err = mach_msg(&msg.Head,       /\* The header *\/ */
> +  /*                MACH_RCV_MSG, */
> +  /*                0, */
> +  /*                sizeof (msg),    /\* Max receive Size *\/ */
> +  /*                excp, */
> +  /*                1000, */
> +  /*                MACH_PORT_NULL); */
> +
> +  // FIXME: maybe MIG should provide this prototype?
> +  boolean_t exc_server
> +    (mach_msg_header_t *InHeadP, mach_msg_header_t *OutHeadP);
> +
> +  memset(&last_exc, 0, sizeof(last_exc));
> +  test_thread_start(mach_task_self(), test_bad_syscall_num, NULL);
> +  ASSERT_RET(simple_msg_server(exc_server, excp, 1), "error in exc server");
> +  ASSERT((last_exc.exception == EXC_BAD_INSTRUCTION) && (last_exc.code == 
> EXC_I386_INVOP),
> +         "bad exception for test_bad_syscall_num()");
> +
> +  memset(&last_exc, 0, sizeof(last_exc));
> +  test_thread_start(mach_task_self(), test_syscall_bad_arg_on_stack, NULL);
> +  ASSERT_RET(simple_msg_server(exc_server, excp, 1), "error in exc server");
> +  ASSERT((last_exc.exception == EXC_BAD_ACCESS) && (last_exc.code == 
> KERN_INVALID_ADDRESS),
> +         "bad exception for test_syscall_bad_arg_on_stack()");
> +
> +  return 0;
> +}
> -- 
> 2.39.2