re PR sanitizer/80998 (Implement -fsanitize=pointer-overflow)

	PR sanitizer/80998
	* sanopt.c (pass_sanopt::execute): Handle IFN_UBSAN_PTR.
	* tree-ssa-alias.c (call_may_clobber_ref_p_1): Likewise.
	* flag-types.h (enum sanitize_code): Add SANITIZER_POINTER_OVERFLOW.
	Or it into SANITIZER_UNDEFINED.
	* ubsan.c: Include gimple-fold.h and varasm.h.
	(ubsan_expand_ptr_ifn): New function.
	(instrument_pointer_overflow): New function.
	(maybe_instrument_pointer_overflow): New function.
	(instrument_object_size): Formatting fix.
	(pass_ubsan::execute): Call instrument_pointer_overflow
	and maybe_instrument_pointer_overflow.
	* internal-fn.c (expand_UBSAN_PTR): New function.
	* ubsan.h (ubsan_expand_ptr_ifn): Declare.
	* sanitizer.def (__ubsan_handle_pointer_overflow,
	__ubsan_handle_pointer_overflow_abort): New builtins.
	* tree-ssa-tail-merge.c (merge_stmts_p): Handle IFN_UBSAN_PTR.
	* internal-fn.def (UBSAN_PTR): New internal function.
	* opts.c (sanitizer_opts): Add pointer-overflow.
	* lto-streamer-in.c (input_function): Handle IFN_UBSAN_PTR.
	* fold-const.c (build_range_check): Compute pointer range check in
	integral type if pointer arithmetics would be needed.  Formatting
	fixes.
gcc/testsuite/
	* c-c++-common/ubsan/ptr-overflow-1.c: New test.
	* c-c++-common/ubsan/ptr-overflow-2.c: New test.
libsanitizer/
	* ubsan/ubsan_handlers.cc: Cherry-pick upstream r304461.
	* ubsan/ubsan_checks.inc: Likewise.
	* ubsan/ubsan_handlers.h: Likewise.

From-SVN: r250656

4 files changed, 46 insertions, 0 deletions

diff --git a/libsanitizer/ChangeLog b/libsanitizer/ChangeLog
index 192318390d3..75c9f0cecd0 100644
--- a/libsanitizer/ChangeLog
+++ b/libsanitizer/ChangeLog
@@ -1,3 +1,10 @@
+2017-07-28  Jakub Jelinek  <jakub@redhat.com>
+
+	PR sanitizer/80998
+	* ubsan/ubsan_handlers.cc: Cherry-pick upstream r304461.
+	* ubsan/ubsan_checks.inc: Likewise.
+	* ubsan/ubsan_handlers.h: Likewise.
+
 2017-07-14  Jakub Jelinek  <jakub@redhat.com>
 
 	PR sanitizer/81066
diff --git a/libsanitizer/ubsan/ubsan_checks.inc b/libsanitizer/ubsan/ubsan_checks.inc
index ea85877198a..31e9495e301 100644
--- a/libsanitizer/ubsan/ubsan_checks.inc
+++ b/libsanitizer/ubsan/ubsan_checks.inc
@@ -17,6 +17,7 @@
 
 UBSAN_CHECK(GenericUB, "undefined-behavior", "undefined")
 UBSAN_CHECK(NullPointerUse, "null-pointer-use", "null")
+UBSAN_CHECK(PointerOverflow, "pointer-overflow", "pointer-overflow")
 UBSAN_CHECK(MisalignedPointerUse, "misaligned-pointer-use", "alignment")
 UBSAN_CHECK(InsufficientObjectSize, "insufficient-object-size", "object-size")
 UBSAN_CHECK(SignedIntegerOverflow, "signed-integer-overflow",
diff --git a/libsanitizer/ubsan/ubsan_handlers.cc b/libsanitizer/ubsan/ubsan_handlers.cc
index 5631e457a1c..761ccef63f3 100644
--- a/libsanitizer/ubsan/ubsan_handlers.cc
+++ b/libsanitizer/ubsan/ubsan_handlers.cc
@@ -521,6 +521,37 @@ void __ubsan::__ubsan_handle_nonnull_arg_abort(NonNullArgData *Data) {
   Die();
 }
 
+static void handlePointerOverflowImpl(PointerOverflowData *Data,
+                                      ValueHandle Base,
+                                      ValueHandle Result,
+                                      ReportOptions Opts) {
+  SourceLocation Loc = Data->Loc.acquire();
+  ErrorType ET = ErrorType::PointerOverflow;
+
+  if (ignoreReport(Loc, Opts, ET))
+    return;
+
+  ScopedReport R(Opts, Loc, ET);
+
+  Diag(Loc, DL_Error, "pointer index expression with base %0 overflowed to %1")
+    << (void *)Base << (void*)Result;
+}
+
+void __ubsan::__ubsan_handle_pointer_overflow(PointerOverflowData *Data,
+                                              ValueHandle Base,
+                                              ValueHandle Result) {
+  GET_REPORT_OPTIONS(false);
+  handlePointerOverflowImpl(Data, Base, Result, Opts);
+}
+
+void __ubsan::__ubsan_handle_pointer_overflow_abort(PointerOverflowData *Data,
+                                                    ValueHandle Base,
+                                                    ValueHandle Result) {
+  GET_REPORT_OPTIONS(true);
+  handlePointerOverflowImpl(Data, Base, Result, Opts);
+  Die();
+}
+
 static void handleCFIBadIcall(CFICheckFailData *Data, ValueHandle Function,
                               ReportOptions Opts) {
   if (Data->CheckKind != CFITCK_ICall)
diff --git a/libsanitizer/ubsan/ubsan_handlers.h b/libsanitizer/ubsan/ubsan_handlers.h
index 394c9eac298..d04554acee3 100644
--- a/libsanitizer/ubsan/ubsan_handlers.h
+++ b/libsanitizer/ubsan/ubsan_handlers.h
@@ -146,6 +146,13 @@ struct NonNullArgData {
 /// \brief Handle passing null pointer to function with nonnull attribute.
 RECOVERABLE(nonnull_arg, NonNullArgData *Data)
 
+struct PointerOverflowData {
+  SourceLocation Loc;
+};
+
+RECOVERABLE(pointer_overflow, PointerOverflowData *Data, ValueHandle Base,
+            ValueHandle Result)
+
 /// \brief Known CFI check kinds.
 /// Keep in sync with the enum of the same name in CodeGenFunction.h
 enum CFITypeCheckKind : unsigned char {