[compiler-rt] [scudo] Add errno description to mmap failure. (PR #87713)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: Christopher Ferris (cferris1000)

<details>
<summary>Changes</summary>

Added unit tests for all of the linux report error functions.

---
Full diff: https://github.com/llvm/llvm-project/pull/87713.diff


2 Files Affected:

- (modified) compiler-rt/lib/scudo/standalone/report_linux.cpp (+3-2) 
- (modified) compiler-rt/lib/scudo/standalone/tests/report_test.cpp (+25) 


``````````diff
diff --git a/compiler-rt/lib/scudo/standalone/report_linux.cpp b/compiler-rt/lib/scudo/standalone/report_linux.cpp
index dfddef3324bd61..ecfc69258374d0 100644
--- a/compiler-rt/lib/scudo/standalone/report_linux.cpp
+++ b/compiler-rt/lib/scudo/standalone/report_linux.cpp
@@ -25,9 +25,10 @@ namespace scudo {
 // Fatal internal map() error (potentially OOM related).
 void NORETURN reportMapError(uptr SizeIfOOM) {
   ScopedString Error;
-  Error.append("Scudo ERROR: internal map failure");
+  Error.append("Scudo ERROR: internal map failure (error desc=%s)",
+               strerror(errno));
   if (SizeIfOOM) {
-    Error.append(" (NO MEMORY) requesting %zuKB", SizeIfOOM >> 10);
+    Error.append(" requesting %zuKB", SizeIfOOM >> 10);
   }
   Error.append("\n");
   reportRawError(Error.data());
diff --git a/compiler-rt/lib/scudo/standalone/tests/report_test.cpp b/compiler-rt/lib/scudo/standalone/tests/report_test.cpp
index 92f1ee813036cd..2c790247a2f6e2 100644
--- a/compiler-rt/lib/scudo/standalone/tests/report_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/report_test.cpp
@@ -53,3 +53,28 @@ TEST(ScudoReportDeathTest, CSpecific) {
   EXPECT_DEATH(scudo::reportInvalidAlignedAllocAlignment(123, 456),
                "Scudo ERROR.*123.*456");
 }
+
+#if SCUDO_LINUX || SCUDO_TRUSTY || SCUDO_ANDROID
+#include "report_linux.h"
+
+#include <errno.h>
+#include <sys/mman.h>
+
+TEST(ScudoReportDeathTest, Linux) {
+  errno = ENOMEM;
+  EXPECT_DEATH(scudo::reportMapError(),
+               "Scudo ERROR:.*internal map failure \\(error desc=.*\\)\\s*$");
+  errno = ENOMEM;
+  EXPECT_DEATH(scudo::reportMapError(1024U),
+               "Scudo ERROR:.*internal map failure \\(error desc=.*\\) "
+               "requesting 1KB\\s*$");
+  errno = ENOMEM;
+  EXPECT_DEATH(scudo::reportUnmapError(0x1000U, 100U),
+               "Scudo ERROR:.*internal unmap failure \\(error desc=.*\\) Addr "
+               "0x1000 Size 100\\s*$");
+  errno = ENOMEM;
+  EXPECT_DEATH(scudo::reportProtectError(0x1000U, 100U, PROT_READ),
+               "Scudo ERROR:.*internal protect failure \\(error desc=.*\\) "
+               "Addr 0x1000 Size 100 Prot 1\\s*$");
+}
+#endif

``````````

</details>


https://github.com/llvm/llvm-project/pull/87713