[compiler-rt] [scudo] Change tests that use setrlimit to cause mmap to fail. (PR #87004)

[Christopher Ferris via llvm-commits]

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@@ -129,16 +129,30 @@ TEST(ScudoStringsTest, Padding) {
 }
 
 #if defined(__linux__)
+
+#include <sys/mman.h>
 #include <sys/resource.h>
 
 TEST(ScudoStringsTest, CapacityIncreaseFails) {
   scudo::ScopedString Str;
 
   rlimit Limit = {};
   EXPECT_EQ(0, getrlimit(RLIMIT_AS, &Limit));
+
   rlimit EmptyLimit = {.rlim_cur = 0, .rlim_max = Limit.rlim_max};
   EXPECT_EQ(0, setrlimit(RLIMIT_AS, &EmptyLimit));
 
+#if !SCUDO_ANDROID
+  // qemu does not honor the setrlimit, so verify before proceeding.
+  void *ptr = mmap(nullptr, 100, PROT_READ | PROT_WRITE,
+                   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+  if (ptr != MAP_FAILED) {
+    munmap(ptr, 100);
+    setrlimit(RLIMIT_AS, &Limit);
+    GTEST_SKIP() << "Limiting address space does not prevent mmap.";
+  }
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cferris1000 wrote:

Done.

https://github.com/llvm/llvm-project/pull/87004