From 6ddcb7dc7dff20efb0e40246e3d2d9e0c0e708d5 Mon Sep 17 00:00:00 2001
From: Julian Seward <jseward@acm.org>
Date: Fri, 11 Mar 2005 14:12:38 +0000
Subject: [PATCH] Detect and reject misaligned args for mmap.  This makes
 none/tests/map_unaligned work.  The PRE handlers for sys_mmap and
 sys_old_mmap are more convoluted than I would like, and might benefit from a
 rewrite.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3284
---
 coregrind/vg_syscalls.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/coregrind/vg_syscalls.c b/coregrind/vg_syscalls.c
index 4a5e6649b..8abdea903 100644
--- a/coregrind/vg_syscalls.c
+++ b/coregrind/vg_syscalls.c
@@ -4054,6 +4054,12 @@ PRE(old_mmap, Special)
       return;
    }
 
+   if (/*(a4 & VKI_MAP_FIXED) &&*/ (0 != (a1 & (VKI_PAGE_SIZE-1)))) {
+      /* zap any misaligned addresses. */
+      SET_RESULT( -VKI_EINVAL );
+      return;
+   }
+
    if (a4 & VKI_MAP_FIXED) {
       if (!VG_(valid_client_addr)(a1, a2, tid, "old_mmap")) {
          PRINT("old_mmap failing: %p-%p\n", a1, a1+a2);
@@ -4098,6 +4104,12 @@ PRE(sys_mmap2, 0)
       return;
    }
 
+   if (/*(ARG4 & VKI_MAP_FIXED) && */ (0 != (ARG1 & (VKI_PAGE_SIZE-1)))) {
+      /* zap any misaligned addresses. */
+      SET_RESULT( -VKI_EINVAL );
+      return;
+   }
+
    if (ARG4 & VKI_MAP_FIXED) {
       if (!VG_(valid_client_addr)(ARG1, ARG2, tid, "mmap2"))
 	 SET_RESULT( -VKI_ENOMEM );