[patch] Diff between 3.2.12 and 3.3.1

hardened-3.2-3.3.diff (text/plain), 1.49 KB, created by Ulrich Müller on 2012-04-11 01:52:24 UTC

--- linux-3.2.12-hardened/fs/binfmt_elf.c
+++ linux-3.3.1-hardened-r1/fs/binfmt_elf.c
@@ -1328,11 +1328,6 @@ static int load_elf_binary(struct linux_
 	start_data += load_bias;
 	end_data += load_bias;
 
-#ifdef CONFIG_PAX_RANDMMAP
-	if (current->mm->pax_flags & MF_PAX_RANDMMAP)
-		elf_brk += PAGE_SIZE + ((pax_get_random_long() & ((1UL << 22) - 1UL)) << 4);
-#endif
-
 	/* Calling set_brk effectively mmaps the pages that we need
 	 * for the bss and break sections.  We must do this before
 	 * mapping in the interpreter, to make sure it doesn't wind
@@ -1351,6 +1346,30 @@ static int load_elf_binary(struct linux_
 		 */
 	}
 
+#ifdef CONFIG_PAX_RANDMMAP
+	if (current->mm->pax_flags & MF_PAX_RANDMMAP) {
+		unsigned long start, size;
+
+		current->mm->end_data = end_data = elf_brk;
+		start = ELF_PAGEALIGN(elf_brk);
+		size = PAGE_SIZE + ((pax_get_random_long() & ((1UL << 22) - 1UL)) << 4);
+		current->mm->start_brk = start + size;
+		down_write(&current->mm->mmap_sem);
+		retval = -ENOMEM;
+		if (!find_vma_intersection(current->mm, start, start + size + PAGE_SIZE)) {
+			start = do_mmap(NULL, start, size, PROT_NONE, MAP_ANONYMOUS | MAP_FIXED | MAP_PRIVATE, 0);
+			retval = IS_ERR_VALUE(start) ? start : 0;
+		}
+		up_write(&current->mm->mmap_sem);
+		if (retval == 0)
+			retval = set_brk(start + size, start + size + PAGE_SIZE);
+		if (retval < 0) {
+			send_sig(SIGKILL, current, 0);
+			goto out_free_dentry;
+		}
+	}
+#endif
+
 	if (elf_interpreter) {
 		unsigned long uninitialized_var(interp_map_addr);