Commit f843ee6d authored by Andy Whitcroft's avatar Andy Whitcroft Committed by Linus Torvalds
Browse files

xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harder



Kees Cook has pointed out that xfrm_replay_state_esn_len() is subject to
wrapping issues.  To ensure we are correctly ensuring that the two ESN
structures are the same size compare both the overall size as reported
by xfrm_replay_state_esn_len() and the internal length are the same.

CVE-2017-7184
Signed-off-by: default avatarAndy Whitcroft <apw@canonical.com>
Acked-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 677e806d
......@@ -412,7 +412,11 @@ static inline int xfrm_replay_verify_len(struct xfrm_replay_state_esn *replay_es
up = nla_data(rp);
ulen = xfrm_replay_state_esn_len(up);
if (nla_len(rp) < ulen || xfrm_replay_state_esn_len(replay_esn) != ulen)
/* Check the overall length and the internal bitmap length to avoid
* potential overflow. */
if (nla_len(rp) < ulen ||
xfrm_replay_state_esn_len(replay_esn) != ulen ||
replay_esn->bmp_len != up->bmp_len)
return -EINVAL;
if (up->replay_window > up->bmp_len * sizeof(__u32) * 8)
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment