We later subtract 8 when calculating the length of the output message
buffer. If padlength is excessively high, this calculation can underflow
and result in a very large positive value.
Now we properly constrain the value of padlength so underflow shouldn't
be possible.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15134
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
+++ /dev/null
-^samba.unittests.auth.heimdal_gensec_unwrap_des.test_unwrap_with_padding_truncated_0.none
-^samba.unittests.auth.heimdal_gensec_unwrap_des.test_unwrap_with_padding_truncated_1.none
} else {
/* check pad */
ret = _gssapi_verify_pad(input_message_buffer,
- input_message_buffer->length - len,
+ input_message_buffer->length - len - 8,
&padlength);
if (ret)
return ret;
} else {
/* check pad */
ret = _gssapi_verify_pad(input_message_buffer,
- input_message_buffer->length - len,
+ input_message_buffer->length - len - 8,
&padlength);
if (ret)
return ret;