Changeset 33103 in vbox for trunk/src/VBox/Runtime/r3/posix

Timestamp:

Oct 13, 2010 12:46:32 PM (14 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

66634

Message:

RTFileOpen: Use O_CLOEXEC on linux (added in 2.6.23) to avoid racing process creation.

File:

• trunk/src/VBox/Runtime/r3/posix/fileio-posix.cpp (modified) (3 diffs)

trunk/src/VBox/Runtime/r3/posix/fileio-posix.cpp

@@ -139 +139 @@
         fOpenMode |= O_NOINHERIT;
 #endif
+#ifdef O_CLOEXEC
+    static int s_fHave_O_CLOEXEC = 0; /* {-1,0,1}; since Linux 2.6.23 */
+    if (!(fOpen & RTFILE_O_INHERIT) && s_fHave_O_CLOEXEC >= 0)
+        fOpenMode |= O_CLOEXEC;
+#endif
 #ifdef O_NONBLOCK
     if (fOpen & RTFILE_O_NON_BLOCK)
@@ -202 +207 @@
     int fh = open(pszNativeFilename, fOpenMode, fMode);
     int iErr = errno;
+
+#ifdef O_CLOEXEC
+    if (   (fOpenMode & O_CLOEXEC)
+        && s_fHave_O_CLOEXEC == 0)
+    {
+        if (fh < 0 && iErr == EINVAL)
+        {
+            s_fHave_O_CLOEXEC = -1;
+            fh = open(pszNativeFilename, fOpenMode, fMode);
+            iErr = errno;
+        }
+        else if (fh >= 0)
+            s_fHave_O_CLOEXEC = fcntl(fh, F_GETFD, 0) > 0 ? 1 : -1;
+    }
+#endif
+
     rtPathFreeNative(pszNativeFilename, pszFilename);
     if (fh >= 0)
@@ -213 +234 @@
 #ifdef O_NOINHERIT
             &&  !(fOpenMode & O_NOINHERIT)  /* Take care since it might be a zero value dummy. */
+#endif
+#ifdef O_CLOEXEC
+            &&  s_fHave_O_CLOEXEC <= 0
 #endif
             )