[PATCH AUTOSEL 4.19 073/158] xfrm: fix sa selector validation

Sasha Levin
2019-07-15T14:22:28Z

From: Nicolas Dichtel <nicolas.dichtel@6wind.com>

[ Upstream commit b8d6d0079757cbd1b69724cfd1c08e2171c68cee ]

After commit b38ff4075a80, the following command does not work anymore:
$ ip xfrm state add src 10.125.0.2 dst 10.125.0.1 proto esp spi 34 reqid 1 \
mode tunnel enc 'cbc(aes)' 0xb0abdba8b782ad9d364ec81e3a7d82a1 auth-trunc \
'hmac(sha1)' 0xe26609ebd00acb6a4d51fca13e49ea78a72c73e6 96 flag align4

In fact, the selector is not mandatory, allow the user to provide an empty
selector.

Fixes: b38ff4075a80 ("xfrm: Fix xfrm sel prefix length validation")
CC: Anirudh Gupta <anirudh.gupta@sophos.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/xfrm/xfrm_user.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index d80d54e663c0..1484bc99a537 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -166,6 +166,9 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
}

switch (p->sel.family) {
+ case AF_UNSPEC:
+ break;
+
case AF_INET:
if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
goto out;
--
2.20.1