l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv
authorPaul Hüber <phueber@kernsp.in>
Sun, 26 Feb 2017 16:58:19 +0000 (17:58 +0100)
committerDavid S. Miller <davem@davemloft.net>
Mon, 27 Feb 2017 03:57:17 +0000 (22:57 -0500)
commit51fb60eb162ab84c5edf2ae9c63cf0b878e5547e
tree388f0a7c4f8d7920de303e3cadb4e7526f26c06a
parent1ecc9ad02c3d4cf44bc94bffcb3b12e7861b00a7
l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv

l2tp_ip_backlog_recv may not return -1 if the packet gets dropped.
The return value is passed up to ip_local_deliver_finish, which treats
negative values as an IP protocol number for resubmission.

Signed-off-by: Paul Hüber <phueber@kernsp.in>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/l2tp/l2tp_ip.c