[compiler-rt] 78e70ce - [scudo] Remove false DCHECK

[Vitaly Buka via llvm-commits]

Author: Vitaly Buka
Date: 2021-07-01T12:06:33-07:00
New Revision: 78e70cee0d46bb14dcbedec993fbf855a4d13266

URL: https://github.com/llvm/llvm-project/commit/78e70cee0d46bb14dcbedec993fbf855a4d13266
DIFF: https://github.com/llvm/llvm-project/commit/78e70cee0d46bb14dcbedec993fbf855a4d13266.diff

LOG: [scudo] Remove false DCHECK

MTE Cache.store passes MAP_NOACCESS here.

Reviewed By: pcc, cryptoad

Differential Revision: https://reviews.llvm.org/D105266

Added: 
    

Modified: 
    compiler-rt/lib/scudo/standalone/linux.cpp
    compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/scudo/standalone/linux.cpp b/compiler-rt/lib/scudo/standalone/linux.cpp
index dedab61631bc..c77c1bb600d9 100644
--- a/compiler-rt/lib/scudo/standalone/linux.cpp
+++ b/compiler-rt/lib/scudo/standalone/linux.cpp
@@ -58,11 +58,8 @@ void *map(void *Addr, uptr Size, UNUSED const char *Name, uptr Flags,
   if (Flags & MAP_MEMTAG)
     MmapProt |= PROT_MTE;
 #endif
-  if (Addr) {
-    // Currently no scenario for a noaccess mapping with a fixed address.
-    DCHECK_EQ(Flags & MAP_NOACCESS, 0);
+  if (Addr)
     MmapFlags |= MAP_FIXED;
-  }
   void *P = mmap(Addr, Size, MmapProt, MmapFlags, -1, 0);
   if (P == MAP_FAILED) {
     if (!(Flags & MAP_ALLOWNOMEM) || errno != ENOMEM)

diff  --git a/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp b/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
index 6b8a60d386b8..d3b7c486f7c3 100644
--- a/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/secondary_test.cpp
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "memtag.h"
 #include "tests/scudo_unit_test.h"
 
 #include "allocator_config.h"
@@ -20,7 +21,11 @@
 #include <vector>
 
 template <typename Config> static scudo::Options getOptionsForConfig() {
-  return {};
+  if (!Config::MaySupportMemoryTagging || !scudo::archSupportsMemoryTagging())
+    return {};
+  scudo::AtomicOptions AO;
+  AO.set(scudo::OptionBit::UseMemoryTagging);
+  return AO.load();
 }
 
 template <typename Config> static void testSecondaryBasic(void) {