[patch] libffi-3.0.13 emutramp pax patch

libffi-3.0.13-emutramp_pax.patch (text/plain), 1.71 KB, created by Charles Svitlik on 2013-03-24 05:26:30 UTC

--- src/closures.c.orig	2013-03-24 01:18:11.513392828 -0400
+++ src/closures.c	2013-03-24 01:18:25.519217731 -0400
@@ -117,6 +117,7 @@
 #endif /* HAVE_MNTENT */
 #include <sys/param.h>
 #include <pthread.h>
+#include <stdlib.h>
 
 /* We don't want sys/mman.h to be included after we redefine mmap and
    dlmunmap.  */
@@ -125,7 +126,6 @@
 
 #if FFI_MMAP_EXEC_SELINUX
 #include <sys/statfs.h>
-#include <stdlib.h>
 
 static int selinux_enabled = -1;
 
@@ -173,23 +173,39 @@
 #endif /* !FFI_MMAP_EXEC_SELINUX */
 
 /* On PaX enable kernels that have MPROTECT enable we can't use PROT_EXEC. */
-#ifdef FFI_MMAP_EXEC_EMUTRAMP_PAX
-#include <stdlib.h>
-
+#define LINE_BUFFER 1024
 static int emutramp_enabled = -1;
-
+static int pax_emutramp_enable = 0;
 static int
 emutramp_enabled_check (void)
 {
-  if (getenv ("FFI_DISABLE_EMUTRAMP") == NULL)
-    return 1;
+  FILE *f;
+  char first[LINE_BUFFER], second[LINE_BUFFER], conf_line[LINE_BUFFER];
+  f = fopen ("/proc/self/status", "r");
+  if (f == NULL)
+#ifdef FFI_MMAP_EXEC_EMUTRAMP_PAX
+    pax_emutramp_enable = 1;
+#else
+    pax_emutramp_enable = 0;
+#endif
   else
-    return 0;
+    while (fgets (conf_line, LINE_BUFFER, f)) {
+      sscanf (conf_line, "%s %s", first, second);
+      if (!strncmp (first, "PaX:", 4)) {
+        if (second[1] == 'E')
+          pax_emutramp_enable = 1;
+      }
+    }
+  fclose(f);
+  if (pax_emutramp_enable) {
+    if (getenv ("FFI_DISABLE_EMUTRAMP") == NULL)
+      return 1;
+  }
+  return 0;
 }
 
 #define is_emutramp_enabled() (emutramp_enabled >= 0 ? emutramp_enabled \
                                : (emutramp_enabled = emutramp_enabled_check ()))
-#endif /* FFI_MMAP_EXEC_EMUTRAMP_PAX */
 
 #elif defined (__CYGWIN__) || defined(__INTERIX)