From: Andy Whitcroft apw@canonical.com
This patch has been added to the stable tree. If you have any objections, please let us know.
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[ Upstream commit f843ee6dd019bcece3e74e76ad9df0155655d0df ]
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: Andy Whitcroft apw@canonical.com Acked-by: Steffen Klassert steffen.klassert@secunet.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org
Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- net/xfrm/xfrm_user.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 177cb17cf09c..30593cadd428 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -386,7 +386,11 @@ 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)