pull request (net): ipsec 2017-10-09

pull request (net): ipsec 2017-10-09

[Steffen Klassert]

1) Fix some error paths of the IPsec offloading API.

2) Fix a NULL pointer dereference when IPsec is used
   with vti. From Alexey Kodanev.

3) Don't call xfrm_policy_cache_flush under xfrm_state_lock,
   it triggers several locking warnings. From Artem Savkov.

Please pull or let me know if there are problems.

Thanks!

The following changes since commit 1f4f554a72be0d8c164c2f5bc6ba939a1c624fb4:

  net: qualcomm: rmnet: Fix a double free (2017-09-09 14:33:27 -0700)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec.git master

for you to fetch changes up to dd269db84908d4d3f7c0efed85bf9d8939fb0b9b:

  xfrm: don't call xfrm_policy_cache_flush under xfrm_state_lock (2017-09-28 09:39:05 +0200)

----------------------------------------------------------------
Alexey Kodanev (1):
      vti: fix NULL dereference in xfrm_input()

Artem Savkov (1):
      xfrm: don't call xfrm_policy_cache_flush under xfrm_state_lock

Steffen Klassert (2):
      xfrm: Fix deletion of offloaded SAs on failure.
      xfrm: Fix negative device refcount on offload failure.

 net/xfrm/xfrm_device.c | 1 +
 net/xfrm/xfrm_input.c  | 6 ++++--
 net/xfrm/xfrm_state.c  | 4 ++--
 net/xfrm/xfrm_user.c   | 1 +
 4 files changed, 8 insertions(+), 4 deletions(-)

[PATCH 1/4] xfrm: Fix deletion of offloaded SAs on failure.

[Steffen Klassert]

When we off load a SA, it gets pushed to the NIC before we can
add it. In case of a failure, we don't delete this SA from the
NIC. Fix this by calling xfrm_dev_state_delete on failure.

Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")
Reported-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_user.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 2bfbd91..b997f13 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -657,6 +657,7 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	if (err < 0) {
 		x->km.state = XFRM_STATE_DEAD;
+		xfrm_dev_state_delete(x);
 		__xfrm_state_put(x);
 		goto out;
 	}
-- 
2.7.4

[PATCH 2/4] xfrm: Fix negative device refcount on offload failure.

[Steffen Klassert]

Reset the offload device at the xfrm_state if the device was
not able to offload the state. Otherwise we drop the device
refcount twice.

Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")
Reported-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_device.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index acf0010..30e5746 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -91,6 +91,7 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 	}
 
 	if (!dev->xfrmdev_ops || !dev->xfrmdev_ops->xdo_dev_state_add) {
+		xso->dev = NULL;
 		dev_put(dev);
 		return 0;
 	}
-- 
2.7.4

[PATCH 3/4] vti: fix NULL dereference in xfrm_input()

[Steffen Klassert]

From: Alexey Kodanev <alexey.kodanev@oracle.com>

Can be reproduced with LTP tests:
  # icmp-uni-vti.sh -p ah -a sha256 -m tunnel -S fffffffe -k 1 -s 10

IPv4:
  RIP: 0010:xfrm_input+0x7f9/0x870
  ...
  Call Trace:
  <IRQ>
  vti_input+0xaa/0x110 [ip_vti]
  ? skb_free_head+0x21/0x40
  vti_rcv+0x33/0x40 [ip_vti]
  xfrm4_ah_rcv+0x33/0x60
  ip_local_deliver_finish+0x94/0x1e0
  ip_local_deliver+0x6f/0xe0
  ? ip_route_input_noref+0x28/0x50
  ...

  # icmp-uni-vti.sh -6 -p ah -a sha256 -m tunnel -S fffffffe -k 1 -s 10
IPv6:
  RIP: 0010:xfrm_input+0x7f9/0x870
  ...
  Call Trace:
  <IRQ>
  xfrm6_rcv_tnl+0x3c/0x40
  vti6_rcv+0xd5/0xe0 [ip6_vti]
  xfrm6_ah_rcv+0x33/0x60
  ip6_input_finish+0xee/0x460
  ip6_input+0x3f/0xb0
  ip6_rcv_finish+0x45/0xa0
  ipv6_rcv+0x34b/0x540

xfrm_input() invokes xfrm_rcv_cb() -> vti_rcv_cb(), the last callback
might call skb_scrub_packet(), which in turn can reset secpath.

Fix it by adding a check that skb->sp is not NULL.

Fixes: 7e9e9202bccc ("xfrm: Clear RX SKB secpath xfrm_offload")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_input.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 2515cd2..8ac9d32 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -429,7 +429,8 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 	nf_reset(skb);
 
 	if (decaps) {
-		skb->sp->olen = 0;
+		if (skb->sp)
+			skb->sp->olen = 0;
 		skb_dst_drop(skb);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
@@ -440,7 +441,8 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		err = x->inner_mode->afinfo->transport_finish(skb, xfrm_gro || async);
 		if (xfrm_gro) {
-			skb->sp->olen = 0;
+			if (skb->sp)
+				skb->sp->olen = 0;
 			skb_dst_drop(skb);
 			gro_cells_receive(&gro_cells, skb);
 			return err;
-- 
2.7.4

[PATCH 4/4] xfrm: don't call xfrm_policy_cache_flush under xfrm_state_lock

[Steffen Klassert]

From: Artem Savkov <asavkov@redhat.com>

I might be wrong but it doesn't look like xfrm_state_lock is required
for xfrm_policy_cache_flush and calling it under this lock triggers both
"sleeping function called from invalid context" and "possible circular
locking dependency detected" warnings on flush.

Fixes: ec30d78c14a8 xfrm: add xdst pcpu cache
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_state.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 0dab1cd..1221347 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -732,12 +732,12 @@ int xfrm_state_flush(struct net *net, u8 proto, bool task_valid)
 			}
 		}
 	}
+out:
+	spin_unlock_bh(&net->xfrm.xfrm_state_lock);
 	if (cnt) {
 		err = 0;
 		xfrm_policy_cache_flush();
 	}
-out:
-	spin_unlock_bh(&net->xfrm.xfrm_state_lock);
 	return err;
 }
 EXPORT_SYMBOL(xfrm_state_flush);
-- 
2.7.4

Re: pull request (net): ipsec 2017-10-09

[David Miller]

From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Mon, 9 Oct 2017 09:16:35 +0200

> 1) Fix some error paths of the IPsec offloading API.
> 
> 2) Fix a NULL pointer dereference when IPsec is used
>    with vti. From Alexey Kodanev.
> 
> 3) Don't call xfrm_policy_cache_flush under xfrm_state_lock,
>    it triggers several locking warnings. From Artem Savkov.
> 
> Please pull or let me know if there are problems.

Pulled, thank you.