Permit the set_tid_address() syscall.

[eval.git] / box / box.c

diff --git a/box/box.c b/box/box.c
index efbdc31148406a82acdf23ee5dfb68e103d56712..033152a66a278d302df8d095c8504b061b94e47d 100644 (file)
--- a/box/box.c
+++ b/box/box.c
@@ -94,7 +94,6 @@ final_stats(struct rusage *rus)
   timeradd(&rus->ru_utime, &rus->ru_stime, &total);
   total_ms = total.tv_sec*1000 + total.tv_usec/1000;
   gettimeofday(&now, NULL);
-  // FIXME: We are not guaranteed to have start_time always initialized
   timersub(&now, &start_time, &wall);
   wall_ms = wall.tv_sec*1000 + wall.tv_usec/1000;
 
@@ -134,28 +133,42 @@ flush_line(void)
   partial_line = 0;
 }
 
+/* Report an error of the sandbox itself */
 static void NONRET __attribute__((format(printf,1,2)))
 die(char *msg, ...)
 {
   va_list args;
   va_start(args, msg);
   flush_line();
-  vfprintf(stderr, msg, args);
+  char buf[1024];
+  vsnprintf(buf, sizeof(buf), msg, args);
+  meta_printf("status:XX\nmessage:%s\n", buf);
+  fputs(buf, stderr);
   fputc('\n', stderr);
   box_exit(2);
 }
 
+/* Report an error of the program inside the sandbox */
 static void NONRET __attribute__((format(printf,1,2)))
 err(char *msg, ...)
 {
   va_list args;
   va_start(args, msg);
   flush_line();
-  vfprintf(stderr, msg, args);
+  if (msg[0] && msg[1] && msg[2] == ':' && msg[3] == ' ')
+    {
+      meta_printf("status:%c%c\n", msg[0], msg[1]);
+      msg += 4;
+    }
+  char buf[1024];
+  vsnprintf(buf, sizeof(buf), msg, args);
+  meta_printf("message:%s\n", buf);
+  fputs(buf, stderr);
   fputc('\n', stderr);
   box_exit(1);
 }
 
+/* Write a message, but only if in verbose mode */
 static void __attribute__((format(printf,1,2)))
 msg(char *msg, ...)
 {
@@ -255,6 +268,7 @@ static unsigned char syscall_action[NUM_ACTIONS] = {
     S(gettid) = A_YES,
     S(set_thread_area) = A_YES,
     S(get_thread_area) = A_YES,
+    S(set_tid_address) = A_YES,
     S(exit_group) = A_YES,
 
     // Syscalls permitted only in liberal mode
@@ -568,7 +582,7 @@ valid_filename(unsigned long addr)
   static int mem_fd;
 
   if (!file_access)
-    err("File access forbidden");
+    err("FA: File access forbidden");
   if (file_access >= 9)
     return;
 
@@ -589,14 +603,14 @@ valid_filename(unsigned long addr)
          if (l > remains)
            l = remains;
          if (!l)
-           err("Access to file with name too long");
+           err("FA: Access to file with name too long");
          if (lseek64(mem_fd, addr, SEEK_SET) < 0)
            die("lseek64(mem): %m");
          remains = read(mem_fd, end, l);
          if (remains < 0)
            die("read(mem): %m");
          if (!remains)
-           err("Access to file with name out of memory");
+           err("FA: Access to file with name out of memory");
          end += l;
          addr += l;
        }
@@ -626,7 +640,7 @@ valid_filename(unsigned long addr)
       act = match_path_rule(&default_path_rules[i], namebuf);
 
   if (act != A_YES)
-    err("Forbidden access to file `%s'", namebuf);
+    err("FA: Forbidden access to file `%s'", namebuf);
 }
 
 static int
@@ -658,11 +672,17 @@ valid_syscall(struct user *u)
     {
     case __NR_kill:
       if (u->regs.ebx == box_pid)
-       err("Committed suicide by signal %d", (int)u->regs.ecx);
+       {
+         meta_printf("exitsig:%d\n", (int)u->regs.ecx);
+         err("SG: Committed suicide by signal %d", (int)u->regs.ecx);
+       }
       return 0;
     case __NR_tgkill:
       if (u->regs.ebx == box_pid && u->regs.ecx == box_pid)
-       err("Committed suicide by signal %d", (int)u->regs.edx);
+       {
+         meta_printf("exitsig:%d\n", (int)u->regs.edx);
+         err("SG: Committed suicide by signal %d", (int)u->regs.edx);
+       }
       return 0;
     default:
       return 0;
@@ -681,7 +701,8 @@ static void
 signal_int(int unused UNUSED)
 {
   /* Interrupts are fatal, so no synchronization requirements. */
-  err("Interrupted");
+  meta_printf("exitsig:%d\n", SIGINT);
+  err("SG: Interrupted");
 }
 
 static void
@@ -695,7 +716,7 @@ check_timeout(void)
       timersub(&now, &start_time, &wall);
       wall_ms = wall.tv_sec*1000 + wall.tv_usec/1000;
       if (wall_ms > wall_timeout)
-        err("Time limit exceeded (wall clock)");
+        err("TO: Time limit exceeded (wall clock)");
       if (verbose > 1)
         fprintf(stderr, "[wall time check: %d msec]\n", wall_ms);
     }
@@ -734,7 +755,7 @@ check_timeout(void)
       if (verbose > 1)
        fprintf(stderr, "[time check: %d msec]\n", ms);
       if (ms > timeout)
-       err("Time limit exceeded");
+       err("TO: Time limit exceeded");
     }
 }
 
@@ -781,13 +802,23 @@ boxkeeper(void)
        {
          box_pid = 0;
          final_stats(&rus);
-         // FIXME: If the process has exited before being ptraced, signal an internal error
          if (WEXITSTATUS(stat))
-           err("Exited with error status %d", WEXITSTATUS(stat));
+           {
+             if (syscall_count)
+               {
+                 meta_printf("exitcode:%d\n", WEXITSTATUS(stat));
+                 err("RE: Exited with error status %d", WEXITSTATUS(stat));
+               }
+             else
+               {
+                 // Internal error happened inside the child process and it has been already reported.
+                 box_exit(2);
+               }
+           }
          if (timeout && total_ms > timeout)
-           err("Time limit exceeded");
+           err("TO: Time limit exceeded");
          if (wall_timeout && wall_ms > wall_timeout)
-           err("Time limit exceeded (wall clock)");
+           err("TO: Time limit exceeded (wall clock)");
          flush_line();
          fprintf(stderr, "OK (%d.%03d sec real, %d.%03d sec wall, %d syscalls)\n",
              total_ms/1000, total_ms%1000,
@@ -798,7 +829,8 @@ boxkeeper(void)
       if (WIFSIGNALED(stat))
        {
          box_pid = 0;
-         err("Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup"));
+         meta_printf("exitsig:%d\n", WTERMSIG(stat));
+         err("SG: Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup"));
        }
       if (WIFSTOPPED(stat))
        {
@@ -835,7 +867,7 @@ boxkeeper(void)
                      u.regs.orig_eax = 0xffffffff;
                      if (ptrace(PTRACE_SETREGS, box_pid, NULL, &u) < 0)
                        die("ptrace(PTRACE_SETREGS): %m");
-                     err("Forbidden syscall %s", syscall_name(sys, namebuf));
+                     err("FO: Forbidden syscall %s", syscall_name(sys, namebuf));
                    }
                }
              else                                      /* Syscall return */
@@ -848,7 +880,10 @@ boxkeeper(void)
              ptrace(PTRACE_SYSCALL, box_pid, 0, sig);
            }
          else
-           err("Received signal %d", sig);
+           {
+             meta_printf("exitsig:%d", sig);
+             err("SG: Received signal %d", sig);
+           }
        }
       else
        die("wait4: unknown status %x, giving up!", stat);
@@ -935,7 +970,7 @@ Options:\n\
 -v\t\tBe verbose (use multiple times for even more verbosity)\n\
 -w <time>\tSet wall clock time limit (seconds, fractions allowed)\n\
 ");
-  exit(1);
+  exit(2);
 }
 
 int