Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2018-10-01

1) Validate address prefix lengths in the xfrm selector,
   otherwise we may hit undefined behaviour in the
   address matching functions if the prefix is too
   big for the given address family.

2) Fix skb leak on local message size errors.
   From Thadeu Lima de Souza Cascardo.

3) We currently reset the transport header back to the network
   header after a transport mode transformation is applied. This
   leads to an incorrect transport header when multiple transport
   mode transformations are applied. Reset the transport header
   only after all transformations are already applied to fix this.
   From Sowmini Varadhan.

4) We only support one offloaded xfrm, so reset crypto_done after
   the first transformation in xfrm_input(). Otherwise we may call
   the wrong input method for subsequent transformations.
   From Sowmini Varadhan.

5) Fix NULL pointer dereference when skb_dst_force clears the dst_entry.
   skb_dst_force does not really force a dst refcount anymore, it might
   clear it instead. xfrm code did not expect this, add a check to not
   dereference skb_dst() if it was cleared by skb_dst_force.

6) Validate xfrm template mode, otherwise we can get a stack-out-of-bounds
   read in xfrm_state_find. From Sean Tranchetti.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 30 insertions, 6 deletions

diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index bcfc00e88756da..f8de2482a52923 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -67,6 +67,7 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async)
 
 	if (xo && (xo->flags & XFRM_GRO)) {
 		skb_mac_header_rebuild(skb);
+		skb_reset_transport_header(skb);
 		return 0;
 	}
 
diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c
index 3d36644890bb6d..1ad2c2c4e250f8 100644
--- a/net/ipv4/xfrm4_mode_transport.c
+++ b/net/ipv4/xfrm4_mode_transport.c
@@ -46,7 +46,6 @@ static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
-	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -54,8 +53,7 @@ static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 		skb->network_header = skb->transport_header;
 	}
 	ip_hdr(skb)->tot_len = htons(skb->len + ihl);
-	if (!xo || !(xo->flags & XFRM_GRO))
-		skb_reset_transport_header(skb);
+	skb_reset_transport_header(skb);
 	return 0;
 }
 
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 841f4a07438e83..9ef490dddcea23 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -59,6 +59,7 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async)
 
 	if (xo && (xo->flags & XFRM_GRO)) {
 		skb_mac_header_rebuild(skb);
+		skb_reset_transport_header(skb);
 		return -1;
 	}
 
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c
index 9ad07a91708ef7..3c29da5defe6c3 100644
--- a/net/ipv6/xfrm6_mode_transport.c
+++ b/net/ipv6/xfrm6_mode_transport.c
@@ -51,7 +51,6 @@ static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
-	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -60,8 +59,7 @@ static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 	}
 	ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 					   sizeof(struct ipv6hdr));
-	if (!xo || !(xo->flags & XFRM_GRO))
-		skb_reset_transport_header(skb);
+	skb_reset_transport_header(skb);
 	return 0;
 }
 
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 5959ce9620eb92..6a74080005cf6a 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -170,9 +170,11 @@ static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 
 	if (toobig && xfrm6_local_dontfrag(skb)) {
 		xfrm6_local_rxpmtu(skb, mtu);
+		kfree_skb(skb);
 		return -EMSGSIZE;
 	} else if (!skb->ignore_df && toobig && skb->sk) {
 		xfrm_local_error(skb, mtu);
+		kfree_skb(skb);
 		return -EMSGSIZE;
 	}
 
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index b89c9c7f8c5c12..be3520e429c9f9 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -458,6 +458,7 @@ resume:
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 			goto drop;
 		}
+		crypto_done = false;
 	} while (!err);
 
 	err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 45ba07ab3e4f8d..261995d37ced3a 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -100,6 +100,10 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 		spin_unlock_bh(&x->lock);
 
 		skb_dst_force(skb);
+		if (!skb_dst(skb)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+			goto error_nolock;
+		}
 
 		if (xfrm_offload(skb)) {
 			x->type_offload->encap(x, skb);
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 3110c3fbee2099..f094d4b3520d97 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2491,6 +2491,10 @@ int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 	}
 
 	skb_dst_force(skb);
+	if (!skb_dst(skb)) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
+		return 0;
+	}
 
 	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
 	if (IS_ERR(dst)) {
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 4791aa8b818583..df7ca2dabc4888 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -151,10 +151,16 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
 	err = -EINVAL;
 	switch (p->family) {
 	case AF_INET:
+		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
+			goto out;
+
 		break;
 
 	case AF_INET6:
 #if IS_ENABLED(CONFIG_IPV6)
+		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
+			goto out;
+
 		break;
 #else
 		err = -EAFNOSUPPORT;
@@ -1396,10 +1402,16 @@ static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
 
 	switch (p->sel.family) {
 	case AF_INET:
+		if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
+			return -EINVAL;
+
 		break;
 
 	case AF_INET6:
 #if IS_ENABLED(CONFIG_IPV6)
+		if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
+			return -EINVAL;
+
 		break;
 #else
 		return  -EAFNOSUPPORT;
@@ -1480,6 +1492,9 @@ static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
 		    (ut[i].family != prev_family))
 			return -EINVAL;
 
+		if (ut[i].mode >= XFRM_MODE_MAX)
+			return -EINVAL;
+
 		prev_family = ut[i].family;
 
 		switch (ut[i].family) {