Fix for CVE-2014-0195

A buffer overrun attack can be triggered by sending invalid DTLS fragments
to an OpenSSL DTLS client or server. This is potentially exploitable to
run arbitrary code on a vulnerable client or server.

Fixed by adding consistency check for DTLS fragments.

Thanks to Jüri Aedla for reporting this issue.

(Imported from upstream's eb6508d50c9a314b88ac155bd378cbd79a117c92)
This commit is contained in:
Adam Langley 2014-06-20 12:00:00 -07:00
parent ce7f9caa98
commit bed2214b3e

View File

@ -635,7 +635,16 @@ dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok)
frag->msg_header.frag_off = 0;
}
else
{
frag = (hm_fragment*) item->data;
if (frag->msg_header.msg_len != msg_hdr->msg_len)
{
item = NULL;
frag = NULL;
goto err;
}
}
/* If message is already reassembled, this must be a
* retransmit and can be dropped.