ecryptfs: don't allow mmap when the lower fs doesn't support it

[pandora-kernel.git] / fs / compat.c

diff --git a/fs/compat.c b/fs/compat.c
index e07a3d3..4bf082d 100644 (file)
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -572,6 +572,10 @@ ssize_t compat_rw_copy_check_uvector(int type,
        }
        *ret_pointer = iov;
 
+       ret = -EFAULT;
+       if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
+               goto out;
+
        /*
         * Single unix specification:
         * We should -EINVAL if an element length is not >= 0 and fitting an
@@ -1103,17 +1107,12 @@ static ssize_t compat_do_readv_writev(int type, struct file *file,
        if (!file->f_op)
                goto out;
 
-       ret = -EFAULT;
-       if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
-               goto out;
-
-       tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs,
+       ret = compat_rw_copy_check_uvector(type, uvector, nr_segs,
                                               UIO_FASTIOV, iovstack, &iov, 1);
-       if (tot_len == 0) {
-               ret = 0;
+       if (ret <= 0)
                goto out;
-       }
 
+       tot_len = ret;
        ret = rw_verify_area(type, file, pos, tot_len);
        if (ret < 0)
                goto out;