gdbserver: Fix crash when QTinit is handled with no inferior process attached

When gdbserver is called with --multi and attach has not been called yet
and tstart is called on the gdb client, gdbserver would crash.
This patch fixes gdbserver so that it returns E01 to the gdb client.

Also this patch adds a testcase to verify this bug named no-attach-trace.exp

gdb/gdbserver/ChangeLog:
	PR breakpoints/15956
	* tracepoint.c (cmd_qtinit): Add check for current_thread.

gdb/testsuite/ChangeLog:
	* gdb.trace/no-attach-trace.c: New file.
	* gdb.trace/no-attach-trace.exp: New file.

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 25f3adfef3c2cfbd04b6ecb14913b6f15a31a075..4badd9e796e7637327f89c811a90578af6aa41de 100644 (file)
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-10  Antoine Tremblay <antoine.tremblay@ericsson.com>
+
+       PR breakpoints/15956
+       * tracepoint.c (cmd_qtinit): Add check for current_thread.
+
 2015-02-09  Markus Metzger  <markus.t.metzger@intel.com>
 
        * linux-low.c (linux_low_btrace_conf): Print size.

diff --git a/gdb/gdbserver/tracepoint.c b/gdb/gdbserver/tracepoint.c
index 82d6ce5d51e1841a18f60b196435e22a7b7ef150..2382a11a3ea81070df91bbee050799cf66cf6d49 100644 (file)
--- a/gdb/gdbserver/tracepoint.c
+++ b/gdb/gdbserver/tracepoint.c
@@ -2377,6 +2377,13 @@ cmd_qtinit (char *packet)
 {
   struct trace_state_variable *tsv, *prev, *next;
 
+  /* Can't do this command without a pid attached.  */
+  if (current_thread == NULL)
+    {
+      write_enn (packet);
+      return;
+    }
+
   /* Make sure we don't try to read from a trace frame.  */
   current_traceframe = -1;
 

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 4fe771e7d8094ce9ef9085318e5c588ec5803401..c1d76d6ad13eeb38a181a8159151a6566db501bf 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-10  Antoine Tremblay <antoine.tremblay@ericsson.com>
+
+       * gdb.trace/no-attach-trace.c: New file.
+       * gdb.trace/no-attach-trace.exp: New file.
+
 2015-02-09  Mark Wielaard  <mjw@redhat.com>
 
        * gdb.dwarf2/atomic.c: New file.

diff --git a/gdb/testsuite/gdb.trace/Makefile.in b/gdb/testsuite/gdb.trace/Makefile.in
index 2e23223dd18e886cdb94efc7a3589451d30da685..514beab831256a22e62a15d52b9da04a69b857e3 100644 (file)
--- a/gdb/testsuite/gdb.trace/Makefile.in
+++ b/gdb/testsuite/gdb.trace/Makefile.in
@@ -4,8 +4,8 @@ srcdir = @srcdir@
 .PHONY: all clean mostlyclean distclean realclean
 
 PROGS = actions-changed ax backtrace deltrace disconnected-tracing \
-       infotrace packetlen passc-dyn passcount report save-trace tfile \
-       tfind tracecmd tsv unavailable while-dyn while-stepping
+       infotrace no-attach-trace packetlen passc-dyn passcount report \
+       save-trace tfile tfind tracecmd tsv unavailable while-dyn while-stepping
 
 all info install-info dvi install uninstall installcheck check:
        @echo "Nothing to be done for $@..."

diff --git a/gdb/testsuite/gdb.trace/no-attach-trace.c b/gdb/testsuite/gdb.trace/no-attach-trace.c
new file mode 100644 (file)
index 0000000..9b4ada8
--- /dev/null
+++ b/gdb/testsuite/gdb.trace/no-attach-trace.c
@@ -0,0 +1,26 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* This program is intended to be a simple dummy program for gdb to read.  */
+
+#include <unistd.h>
+
+int
+main (void)
+{
+  return 0;
+}

diff --git a/gdb/testsuite/gdb.trace/no-attach-trace.exp b/gdb/testsuite/gdb.trace/no-attach-trace.exp
new file mode 100644 (file)
index 0000000..96135cb
--- /dev/null
+++ b/gdb/testsuite/gdb.trace/no-attach-trace.exp
@@ -0,0 +1,53 @@
+# This testcase is part of GDB, the GNU debugger.
+
+# Copyright 2015 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test that trying to trace without a program attached fails properly.
+
+load_lib trace-support.exp
+
+standard_testfile
+
+if {[prepare_for_testing $testfile.exp $testfile $srcfile debug]} {
+    return -1
+}
+
+if ![runto_main] {
+    fail "Can't run to main to check for trace support"
+    return -1
+}
+
+if { ![gdb_target_supports_trace] } then {
+    unsupported "Current target does not support trace"
+    return 1
+
+}
+
+# Clean test state so that we have no process attached.
+clean_restart $testfile
+
+gdb_test "trace main" \
+    "Tracepoint \[0-9\] at.* file .*$srcfile, line.*" \
+    "set tracepoint on main"
+
+gdb_test "tstart" "Target returns error code.*\."
+
+with_test_prefix "after tstart" {
+    if ![runto_main] {
+       fail "Can't run to main, target may have died unexpectedly"
+       return -1
+    }
+}