[compiler-rt] [sanitizer] add null check (PR #105612)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

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

Author: Wu Yingcong (yingcong-wu)

<details>
<summary>Changes</summary>

`dlsym()` could return nullptr, we should check the return value before using it.

---
Full diff: https://github.com/llvm/llvm-project/pull/105612.diff


1 Files Affected:

- (modified) compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp (+1) 


``````````diff
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
index c3c717bbdbe4c9..f9b0f0e198bf16 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -235,6 +235,7 @@ void InitTlsSize() {
 #    if defined(__aarch64__) || defined(__x86_64__) || \
         defined(__powerpc64__) || defined(__loongarch__)
   void *get_tls_static_info = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
+  CHECK_NE(get_tls_static_info, nullptr);
   size_t tls_align;
   ((void (*)(size_t *, size_t *))get_tls_static_info)(&g_tls_size, &tls_align);
 #    endif

``````````

</details>


https://github.com/llvm/llvm-project/pull/105612