This patch ensures that Path::GetMainExecutable is able to handle the

case where realpath() fails. When this occurs we segfault trying to
create a std::string from a NULL pointer.

Fixes PR5635.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90082 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/System/Unix/Path.inc b/lib/System/Unix/Path.inc
index 4300d6719b3393e26f7174f6babf4f5ae10ebb24..ec2ba7cd9c338d0939690cae264b813ad529e395 100644 (file)
--- a/lib/System/Unix/Path.inc
+++ b/lib/System/Unix/Path.inc
@@ -348,7 +348,9 @@ Path Path::GetMainExecutable(const char *argv0, void *MainAddr) {
   uint32_t size = sizeof(exe_path);
   if (_NSGetExecutablePath(exe_path, &size) == 0) {
     char link_path[MAXPATHLEN];
-    return Path(std::string(realpath(exe_path, link_path)));
+    if (realpath(exe_path, link_path))
+      return Path(std::string(link_path));
+    return Path();
   }
 #elif defined(__FreeBSD__)
   char exe_path[PATH_MAX];
@@ -370,7 +372,9 @@ Path Path::GetMainExecutable(const char *argv0, void *MainAddr) {
   // If the filename is a symlink, we need to resolve and return the location of
   // the actual executable.
   char link_path[MAXPATHLEN];
-  return Path(std::string(realpath(DLInfo.dli_fname, link_path)));
+  if (realpath(DLInfo.dli_fname, link_path))
+    return Path(std::string(link_path));
+  return Path();
 #endif
   return Path();
 }