PR25827, Null pointer dereferencing in scan_unit_for_symbols

[deliverable/binutils-gdb.git] / gdb / inf-ptrace.c

diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index 4ad1cd0622725c90a1414fb5471f032453d60e79..1fa7aa3f73e996024ef9df7c09477fc223b93cc4 100644 (file)
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -37,6 +37,18 @@
 
 \f
 
+static PTRACE_TYPE_RET
+gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
+           PTRACE_TYPE_ARG4 data)
+{
+#ifdef __NetBSD__
+  return ptrace (request, ptid.pid (), addr, data);
+#else
+  pid_t pid = get_ptrace_pid (ptid);
+  return ptrace (request, pid, addr, data);
+#endif
+}
+
 /* A unique_ptr helper to unpush a target.  */
 
 struct target_unpusher
@@ -61,8 +73,8 @@ inf_ptrace_target::~inf_ptrace_target ()
 /* Target hook for follow_fork.  On entry and at return inferior_ptid is
    the ptid of the followed inferior.  */
 
-int
-inf_ptrace_target::follow_fork (int follow_child, int detach_fork)
+bool
+inf_ptrace_target::follow_fork (bool follow_child, bool detach_fork)
 {
   if (!follow_child)
     {
@@ -76,7 +88,7 @@ inf_ptrace_target::follow_fork (int follow_child, int detach_fork)
        perror_with_name (("ptrace"));
     }
 
-  return 0;
+  return false;
 }
 
 int
@@ -136,7 +148,7 @@ inf_ptrace_target::create_inferior (const char *exec_file,
   /* We have something that executes now.  We'll be running through
      the shell at this point (if startup-with-shell is true), but the
      pid shouldn't change.  */
-  add_thread_silent (ptid);
+  add_thread_silent (this, ptid);
 
   unpusher.release ();
 
@@ -235,10 +247,10 @@ inf_ptrace_target::attach (const char *args, int from_tty)
 
   /* Always add a main thread.  If some target extends the ptrace
      target, it should decorate the ptid later with more info.  */
-  thread_info *thr = add_thread_silent (inferior_ptid);
+  thread_info *thr = add_thread_silent (this, inferior_ptid);
   /* Don't consider the thread stopped until we've processed its
      initial SIGSTOP stop.  */
-  set_executing (thr->ptid, true);
+  set_executing (this, thr->ptid, true);
 
   unpusher.release ();
 }
@@ -313,8 +325,9 @@ inf_ptrace_target::kill ()
   target_mourn_inferior (inferior_ptid);
 }
 
-/* Return which PID to pass to ptrace in order to observe/control the
-   tracee identified by PTID.  */
+#ifndef __NetBSD__
+
+/* See inf-ptrace.h.  */
 
 pid_t
 get_ptrace_pid (ptid_t ptid)
@@ -328,6 +341,7 @@ get_ptrace_pid (ptid_t ptid)
     pid = ptid.pid ();
   return pid;
 }
+#endif
 
 /* Resume execution of thread PTID, or all threads if PTID is -1.  If
    STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
@@ -336,15 +350,12 @@ get_ptrace_pid (ptid_t ptid)
 void
 inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
 {
-  pid_t pid;
-  int request;
+  PTRACE_TYPE_ARG1 request;
 
   if (minus_one_ptid == ptid)
     /* Resume all threads.  Traditionally ptrace() only supports
        single-threaded processes, so simply resume the inferior.  */
-    pid = inferior_ptid.pid ();
-  else
-    pid = get_ptrace_pid (ptid);
+    ptid = ptid_t (inferior_ptid.pid ());
 
   if (catch_syscall_enabled () > 0)
     request = PT_SYSCALL;
@@ -354,10 +365,10 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
   if (step)
     {
       /* If this system does not support PT_STEP, a higher level
-         function will have called single_step() to transmute the step
-         request into a continue request (by setting breakpoints on
-         all possible successor instructions), so we don't have to
-         worry about that here.  */
+        function will have called the appropriate functions to transmute the
+        step request into a continue request (by setting breakpoints on
+        all possible successor instructions), so we don't have to
+        worry about that here.  */
       request = PT_STEP;
     }
 
@@ -365,7 +376,7 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
      where it was.  If GDB wanted it to start some other way, we have
      already written a new program counter value to the child.  */
   errno = 0;
-  ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
+  gdb_ptrace (request, ptid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
   if (errno != 0)
     perror_with_name (("ptrace"));
 }
@@ -460,7 +471,7 @@ inf_ptrace_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus,
    be non-null.  Return the number of transferred bytes.  */
 
 static ULONGEST
-inf_ptrace_peek_poke (pid_t pid, gdb_byte *readbuf,
+inf_ptrace_peek_poke (ptid_t ptid, gdb_byte *readbuf,
                      const gdb_byte *writebuf,
                      ULONGEST addr, ULONGEST len)
 {
@@ -491,8 +502,8 @@ inf_ptrace_peek_poke (pid_t pid, gdb_byte *readbuf,
       if (readbuf != NULL || chunk < sizeof (PTRACE_TYPE_RET))
        {
          errno = 0;
-         buf.word = ptrace (PT_READ_I, pid,
-                            (PTRACE_TYPE_ARG3)(uintptr_t) addr, 0);
+         buf.word = gdb_ptrace (PT_READ_I, ptid,
+                                (PTRACE_TYPE_ARG3)(uintptr_t) addr, 0);
          if (errno != 0)
            break;
          if (readbuf != NULL)
@@ -502,15 +513,15 @@ inf_ptrace_peek_poke (pid_t pid, gdb_byte *readbuf,
        {
          memcpy (buf.byte + skip, writebuf + n, chunk);
          errno = 0;
-         ptrace (PT_WRITE_D, pid, (PTRACE_TYPE_ARG3)(uintptr_t) addr,
+         gdb_ptrace (PT_WRITE_D, ptid, (PTRACE_TYPE_ARG3)(uintptr_t) addr,
                  buf.word);
          if (errno != 0)
            {
              /* Using the appropriate one (I or D) is necessary for
                 Gould NP1, at least.  */
              errno = 0;
-             ptrace (PT_WRITE_I, pid, (PTRACE_TYPE_ARG3)(uintptr_t) addr,
-                     buf.word);
+             gdb_ptrace (PT_WRITE_I, ptid, (PTRACE_TYPE_ARG3)(uintptr_t) addr,
+                         buf.word);
              if (errno != 0)
                break;
            }
@@ -528,7 +539,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
                                 const gdb_byte *writebuf,
                                 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
 {
-  pid_t pid = get_ptrace_pid (inferior_ptid);
+  ptid_t ptid = inferior_ptid;
 
   switch (object)
     {
@@ -552,7 +563,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
        piod.piod_len = len;
 
        errno = 0;
-       if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+       if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
          {
            /* Return the actual number of bytes read or written.  */
            *xfered_len = piod.piod_len;
@@ -565,7 +576,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
          return TARGET_XFER_EOF;
       }
 #endif
-      *xfered_len = inf_ptrace_peek_poke (pid, readbuf, writebuf,
+      *xfered_len = inf_ptrace_peek_poke (ptid, readbuf, writebuf,
                                          offset, len);
       return *xfered_len != 0 ? TARGET_XFER_OK : TARGET_XFER_EOF;
 
@@ -588,7 +599,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
        piod.piod_len = len;
 
        errno = 0;
-       if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+       if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
          {
            /* Return the actual number of bytes read or written.  */
            *xfered_len = piod.piod_len;