2019-03-06 08:34:26

by Myungho Jung

Subject: [PATCH] xfrm: Reset secpath in xfrm failure

In esp4_gro_receive() and esp6_gro_receive(), secpath can be allocated
without adding xfrm state to xvec. Then, sp->xvec[sp->len - 1] would
fail and result in dereferencing invalid pointer in esp4_gso_segment()
and esp6_gso_segment(). Reset secpath if xfrm function returns error.

Reported-by: [email protected]
Signed-off-by: Myungho Jung <[email protected]>
---
net/ipv4/esp4_offload.c | 9 +++++++--
net/ipv6/esp6_offload.c | 9 +++++++--
2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c
index 8756e0e790d2..7329e40c73f6 100644
--- a/net/ipv4/esp4_offload.c
+++ b/net/ipv4/esp4_offload.c
@@ -51,14 +51,18 @@ static struct sk_buff *esp4_gro_receive(struct list_head *head,
if (!sp)
goto out;

- if (sp->len == XFRM_MAX_DEPTH)
+ if (sp->len == XFRM_MAX_DEPTH) {
+ secpath_reset(skb);
goto out;
+ }

x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
(xfrm_address_t *)&ip_hdr(skb)->daddr,
spi, IPPROTO_ESP, AF_INET);
- if (!x)
+ if (!x) {
+ secpath_reset(skb);
goto out;
+ }

sp->xvec[sp->len++] = x;
sp->olen++;
@@ -66,6 +70,7 @@ static struct sk_buff *esp4_gro_receive(struct list_head *head,
xo = xfrm_offload(skb);
if (!xo) {
xfrm_state_put(x);
+ secpath_reset(skb);
goto out;
}
}
diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index d46b4eb645c2..399c688d192e 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -73,14 +73,18 @@ static struct sk_buff *esp6_gro_receive(struct list_head *head,
if (!sp)
goto out;

- if (sp->len == XFRM_MAX_DEPTH)
+ if (sp->len == XFRM_MAX_DEPTH) {
+ secpath_reset(skb);
goto out;
+ }

x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
(xfrm_address_t *)&ipv6_hdr(skb)->daddr,
spi, IPPROTO_ESP, AF_INET6);
- if (!x)
+ if (!x) {
+ secpath_reset(skb);
goto out;
+ }

sp->xvec[sp->len++] = x;
sp->olen++;
@@ -88,6 +92,7 @@ static struct sk_buff *esp6_gro_receive(struct list_head *head,
xo = xfrm_offload(skb);
if (!xo) {
xfrm_state_put(x);
+ secpath_reset(skb);
goto out;
}
}
--
2.17.1

2019-03-06 11:48:13

by Steffen Klassert

Subject: Re: [PATCH] xfrm: Reset secpath in xfrm failure

On Wed, Mar 06, 2019 at 04:33:08PM +0900, Myungho Jung wrote:
> In esp4_gro_receive() and esp6_gro_receive(), secpath can be allocated
> without adding xfrm state to xvec. Then, sp->xvec[sp->len - 1] would
> fail and result in dereferencing invalid pointer in esp4_gso_segment()
> and esp6_gso_segment(). Reset secpath if xfrm function returns error.
>
> Reported-by: [email protected]
> Signed-off-by: Myungho Jung <[email protected]>

The patch itself looks ok, but please add a 'Fixes' tag to
the commit message.

Thanks!

2019-03-06 21:19:05

by Myungho Jung

Subject: Re: [PATCH] xfrm: Reset secpath in xfrm failure

On Wed, Mar 06, 2019 at 12:35:43PM +0100, Steffen Klassert wrote:
> On Wed, Mar 06, 2019 at 04:33:08PM +0900, Myungho Jung wrote:
> > In esp4_gro_receive() and esp6_gro_receive(), secpath can be allocated
> > without adding xfrm state to xvec. Then, sp->xvec[sp->len - 1] would
> > fail and result in dereferencing invalid pointer in esp4_gso_segment()
> > and esp6_gso_segment(). Reset secpath if xfrm function returns error.
> >
> > Reported-by: [email protected]
> > Signed-off-by: Myungho Jung <[email protected]>
>
> The patch itself looks ok, but please add a 'Fixes' tag to
> the commit message.
>
> Thanks!

Hi Steffen,

Thanks for reviewing the change. I'll add fixes tag and resubmit it.

Thanks,
Myungho