Prevent resizes bigger than 2GBytes

[yaffs2.git] / yaffs_fs.c

diff --git a/yaffs_fs.c b/yaffs_fs.c
index 39de0740d28ae2d9743f5b019188574081c93bdd..8034a066edd39f72414692656d60355cd360bdf6 100644 (file)
--- a/yaffs_fs.c
+++ b/yaffs_fs.c
@@ -32,7 +32,7 @@
  */
 
 const char *yaffs_fs_c_version =
-    "$Id: yaffs_fs.c,v 1.91 2010-01-11 04:06:46 charles Exp $";
+    "$Id: yaffs_fs.c,v 1.93 2010-02-10 03:54:08 charles Exp $";
 extern const char *yaffs_guts_c_version;
 
 #include <linux/version.h>
@@ -324,6 +324,17 @@ static const struct file_operations yaffs_file_operations = {
 };
 #endif
 
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25))
+static void zero_user_segment(struct page *page, unsigned start, unsigned end)
+{
+       void * kaddr = kmap_atomic(page, KM_USER0);
+       memset(kaddr + start, 0, end - start);
+       kunmap_atomic(kaddr, KM_USER0);
+       flush_dcache_page(page);
+}
+#endif
+
+
 static const struct inode_operations yaffs_file_inode_operations = {
        .setattr = yaffs_setattr,
 };
@@ -1651,14 +1662,20 @@ static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
 static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
 {
        struct inode *inode = dentry->d_inode;
-       int error;
+       int error = 0;
        yaffs_Device *dev;
 
        T(YAFFS_TRACE_OS,
                ("yaffs_setattr of object %d\n",
                yaffs_InodeToObject(inode)->objectId));
 
-       error = inode_change_ok(inode, attr);
+       /* Fail if a requested resize >= 2GB */         
+       if (attr->ia_valid & ATTR_SIZE &&
+               (attr->ia_size >> 31))
+               error = -EINVAL;
+
+       if (error == 0)
+               error = inode_change_ok(inode, attr);
        if (error == 0) {
                int result;
                if (!error){
@@ -1681,8 +1698,9 @@ static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
                yaffs_GrossUnlock(dev);
 
        }
+
        T(YAFFS_TRACE_OS,
-               ("yaffs_setattr done\n"));
+               ("yaffs_setattr done returning %d\n",error));
 
        return error;
 }