diff options
| author | Alexey Kodanev <alexey.kodanev@oracle.com> | 2017-09-12 14:53:46 +0300 |
|---|---|---|
| committer | Steffen Klassert <steffen.klassert@secunet.com> | 2017-09-13 10:15:24 +0200 |
| commit | 23e9fcfef1f3d10675acce023592796851bcaf1a (patch) | |
| tree | ba67bbe908788607fbe2cb86ce890113b14596d7 /net/xfrm/xfrm_input.c | |
| parent | 67a63387b1417b5954eedb15f638f1f0bee3da49 (diff) | |
| download | linux-23e9fcfef1f3d10675acce023592796851bcaf1a.tar.bz2 | |
vti: fix NULL dereference in xfrm_input()
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>
Diffstat (limited to 'net/xfrm/xfrm_input.c')
| -rw-r--r-- | net/xfrm/xfrm_input.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c index 2515cd2bc5db..8ac9d32fb79d 100644 --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -429,7 +429,8 @@ resume: 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 @@ resume: 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; |