[PATCH] Instrument aggregate call arguments even with -fsanitize=object-size (PR sanitizer/81094)

[Jakub Jelinek <jakub at redhat dot com>]

Hi!

-fsanitize=object-size is yet another sanitization that ignored aggregate
function arguments.  Fixed thusly (plus some small cleanup for
instrument_null), bootstrapped/regtested on x86_64-linux and i686-linux, ok
for trunk?

2017-06-14  Jakub Jelinek  <jakub@redhat.com>

	PR sanitizer/81094
	* ubsan.c (instrument_null): Add T argument, use it instead
	of computing it based on IS_LHS.
	(instrument_object_size): Likewise.
	(pass_ubsan::execute): Adjust instrument_null and
	instrument_object_size callers to pass gimple_get_lhs or
	gimple_assign_rhs1 result to it.  Use instrument_null instead of
	calling get_base_address and instrument_mem_ref.  Handle
	aggregate call arguments for object-size sanitization.

	* c-c++-common/ubsan/object-size-11.c: New test.

--- gcc/ubsan.c.jj	2017-06-14 14:40:39.000000000 +0200
+++ gcc/ubsan.c	2017-06-14 14:49:17.702131958 +0200
@@ -1204,10 +1204,8 @@ instrument_mem_ref (tree mem, tree base,
 /* Perform the pointer instrumentation.  */
 
 static void
-instrument_null (gimple_stmt_iterator gsi, bool is_lhs)
+instrument_null (gimple_stmt_iterator gsi, tree t, bool is_lhs)
 {
-  gimple *stmt = gsi_stmt (gsi);
-  tree t = is_lhs ? gimple_get_lhs (stmt) : gimple_assign_rhs1 (stmt);
   /* Handle also e.g. &s->i.  */
   if (TREE_CODE (t) == ADDR_EXPR)
     t = TREE_OPERAND (t, 0);
@@ -1754,11 +1752,10 @@ instrument_nonnull_return (gimple_stmt_i
    points to an out-of-bounds location.  */
 
 static void
-instrument_object_size (gimple_stmt_iterator *gsi, bool is_lhs)
+instrument_object_size (gimple_stmt_iterator *gsi, tree t, bool is_lhs)
 {
   gimple *stmt = gsi_stmt (*gsi);
   location_t loc = gimple_location (stmt);
-  tree t = is_lhs ? gimple_get_lhs (stmt) : gimple_assign_rhs1 (stmt);
   tree type;
   tree index = NULL_TREE;
   HOST_WIDE_INT size_in_bytes;
@@ -1989,9 +1986,9 @@ pass_ubsan::execute (function *fun)
 	  if (sanitize_flags_p (SANITIZE_NULL | SANITIZE_ALIGNMENT, fun->decl))
 	    {
 	      if (gimple_store_p (stmt))
-		instrument_null (gsi, true);
+		instrument_null (gsi, gimple_get_lhs (stmt), true);
 	      if (gimple_assign_single_p (stmt))
-		instrument_null (gsi, false);
+		instrument_null (gsi, gimple_assign_rhs1 (stmt), false);
 	      if (is_gimple_call (stmt))
 		{
 		  unsigned args_num = gimple_call_num_args (stmt);
@@ -2000,10 +1997,7 @@ pass_ubsan::execute (function *fun)
 		      tree arg = gimple_call_arg (stmt, i);
 		      if (is_gimple_reg (arg) || is_gimple_min_invariant (arg))
 			continue;
-		      tree base = get_base_address (arg);
-		      if (TREE_CODE (base) == MEM_REF
-			  && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
-			instrument_mem_ref (arg, base, &gsi, false);
+		      instrument_null (gsi, arg, false);
 		    }
 		}
 	    }
@@ -2033,9 +2027,21 @@ pass_ubsan::execute (function *fun)
 	  if (sanitize_flags_p (SANITIZE_OBJECT_SIZE, fun->decl))
 	    {
 	      if (gimple_store_p (stmt))
-		instrument_object_size (&gsi, true);
+		instrument_object_size (&gsi, gimple_get_lhs (stmt), true);
 	      if (gimple_assign_load_p (stmt))
-		instrument_object_size (&gsi, false);
+		instrument_object_size (&gsi, gimple_assign_rhs1 (stmt),
+					false);
+	      if (is_gimple_call (stmt))
+		{
+		  unsigned args_num = gimple_call_num_args (stmt);
+		  for (unsigned i = 0; i < args_num; ++i)
+		    {
+		      tree arg = gimple_call_arg (stmt, i);
+		      if (is_gimple_reg (arg) || is_gimple_min_invariant (arg))
+			continue;
+		      instrument_object_size (&gsi, arg, false);
+		    }
+		}
 	    }
 
 	  gsi_next (&gsi);
--- gcc/testsuite/c-c++-common/ubsan/object-size-11.c.jj	2017-06-14 16:16:43.192137010 +0200
+++ gcc/testsuite/c-c++-common/ubsan/object-size-11.c	2017-06-14 16:16:22.000000000 +0200
@@ -0,0 +1,53 @@
+/* PR sanitizer/81094 */
+/* { dg-do run } */
+/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
+/* { dg-options "-fsanitize=object-size" } */
+
+#define N 20
+
+struct S { int i; };
+
+__attribute__((noinline, noclone)) void
+f0 (struct S s)
+{
+  asm volatile ("" : : "r" (s.i) : "memory");
+}
+
+__attribute__((noinline, noclone)) void
+f1 (int i)
+{
+  char *orig;
+  struct S *p;
+  orig = (char *) __builtin_calloc (N, sizeof (struct S));
+  p = (struct S *) orig;
+  f0 (*(p + i));
+  f0 (p[i]);
+  p++;
+  f0 (p[i - 1]);
+  f0 (*(p + i - 1));
+  __builtin_free (orig);
+}
+
+/* { dg-output "load of address \[^\n\r]* with insufficient space for an object of type 'struct S'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*note: pointer points here\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\\^\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*load of address \[^\n\r]* with insufficient space for an object of type 'struct S'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*note: pointer points here\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\\^\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*load of address \[^\n\r]* with insufficient space for an object of type 'struct S'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*note: pointer points here\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\\^\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*load of address \[^\n\r]* with insufficient space for an object of type 'struct S'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*note: pointer points here\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*\\^" } */
+
+int
+main ()
+{
+  f1 (N);
+  return 0;
+}

	Jakub