Commits
Alexey Kodanev committed 23e9fcfef1f
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>