[patch] use /proc for pax mark check

libffi-3.0.13-emutramp_pax_log.patch (text/plain), 1.41 KB, created by Magnus Granberg on 2013-04-29 01:01:20 UTC

--- a/src/closures.c	2013-03-17 23:27:11.000000000 +0100
+++ b/src/closures.c	2013-04-29 02:51:01.820465762 +0200
@@ -175,16 +175,39 @@ selinux_enabled_check (void)
 /* On PaX enable kernels that have MPROTECT enable we can't use PROT_EXEC. */
 #ifdef FFI_MMAP_EXEC_EMUTRAMP_PAX
 #include <stdlib.h>
+#include <syslog.h>
 
 static int emutramp_enabled = -1;
 
 static int
 emutramp_enabled_check (void)
 {
-  if (getenv ("FFI_DISABLE_EMUTRAMP") == NULL)
-    return 1;
-  else
-    return 0;
+  char *buf = NULL;
+  size_t len = 0;
+  FILE *f;
+  int ret;
+  f = fopen ("/proc/self/status", "r");
+  if (f == NULL)
+    {
+      /* We can't read the needed info from /proc  */
+      syslog (LOG_INFO, "Can't read /proc/self/status");
+      return 0;
+    }
+  ret = 0;
+
+  while (getline (&buf, &len, f) != -1)
+    if (!strncmp (buf, "PaX:", 4))
+      {
+        char emutramp;
+        if (sscanf (buf, "%*s %*c%c", &emutramp) == 1)
+          ret = (emutramp == 'E');
+        if (ret == 0)
+          syslog (LOG_INFO, "Emutramp in not enable.");
+        break;
+      }
+  free (buf);
+  fclose (f);
+  return ret;
 }
 
 #define is_emutramp_enabled() (emutramp_enabled >= 0 ? emutramp_enabled \
@@ -197,6 +220,7 @@ emutramp_enabled_check (void)
 
 /* Cygwin is Linux-like, but not quite that Linux-like.  */
 #define is_selinux_enabled() 0
+#define is_emutramp_enabled() 0
 
 #endif /* !defined(X86_WIN32) && !defined(X86_WIN64) */