From: notaz <notasas@gmail.com>
Date: Sat, 16 Jan 2016 00:52:43 +0000 (+0200)
Subject: use compat memory layout
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=df608af11ff903836b8a2be235719511df03b025;p=ginge.git

use compat memory layout

seems to help with hiding crocodingus' bugs
---

diff --git a/loader/loader.c b/loader/loader.c
index 8a021df..84758c1 100644
--- a/loader/loader.c
+++ b/loader/loader.c
@@ -15,6 +15,7 @@
 
 #include "header.h"
 #include "realfuncs.h"
+#include "syscalls.h"
 
 char *bin_path;
 char **g_argv;
@@ -76,6 +77,7 @@ int main(int argc, char *argv[])
   long *stack_frame;
   struct stat st;
   char buf[64];
+  long lret;
 
   if (argc < 2) {
     fprintf(stderr, "usage: %s <program> [args]\n", argv[0]);
@@ -84,6 +86,12 @@ int main(int argc, char *argv[])
 
   g_argv = argv;
 
+  lret = g_personality(-1);
+  if (g_syscall_error(lret) != -1) {
+    lret |= 0x0240000; // ADDR_COMPAT_LAYOUT | ADDR_NO_RANDOMIZE
+    g_personality(lret);
+  }
+
   fi = fopen("/proc/self/maps", "r");
   CHECK_NE(fi, NULL, "fopen maps");
 
diff --git a/loader/syscalls.S b/loader/syscalls.S
index d478582..f08de56 100644
--- a/loader/syscalls.S
+++ b/loader/syscalls.S
@@ -103,4 +103,5 @@ raw_syscall_easy g_readlink_raw,       __NR_readlink
 raw_syscall_easy g_execve_raw,         __NR_execve
 raw_syscall_easy g_clock_gettime_raw,  __NR_clock_gettime
 raw_syscall_easy g_rt_sigprocmask_raw, __NR_rt_sigprocmask
+raw_syscall_easy g_personality,        __NR_personality
 raw_syscall_easy g_exit_group_raw,     __NR_exit_group
diff --git a/loader/syscalls.h b/loader/syscalls.h
index 9978532..5d38cbb 100644
--- a/loader/syscalls.h
+++ b/loader/syscalls.h
@@ -31,6 +31,7 @@ long g_execve_raw(const char *filename, char * const argv[],
 long g_clock_gettime_raw(int clk_id, const struct timespec *tp);
 long g_rt_sigprocmask_raw(int how, const void *set, void *oldset,
                           size_t sigsetsize);
+long g_personality(long persona);
 long __attribute__((noreturn))
      g_exit_group_raw(int status);