4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Aviv Heller <[email protected]> [ Upstream commit 4ce3dbe397d7b6b15f272ae757c78c35e9e4b61d ] Code path when (encap_type < 0) does not verify the state is valid before progressing. This will result in a crash if, for instance, x->km.state == XFRM_STATE_ACQ. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Signed-off-by: Aviv Heller <[email protected]> Signed-off-by: Yevgeny Kliteynik <[email protected]> Signed-off-by: Steffen Klassert <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- net/xfrm/xfrm_input.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -207,7 +207,7 @@ int xfrm_input(struct sk_buff *skb, int xfrm_address_t *daddr; struct xfrm_mode *inner_mode; u32 mark = skb->mark; - unsigned int family; + unsigned int family = AF_UNSPEC; int decaps = 0; int async = 0; bool xfrm_gro = false; @@ -216,6 +216,16 @@ int xfrm_input(struct sk_buff *skb, int if (encap_type < 0) { x = xfrm_input_state(skb); + + if (unlikely(x->km.state != XFRM_STATE_VALID)) { + if (x->km.state == XFRM_STATE_ACQ) + XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR); + else + XFRM_INC_STATS(net, + LINUX_MIB_XFRMINSTATEINVALID); + goto drop; + } + family = x->outer_mode->afinfo->family; /* An encap_type of -1 indicates async resumption. */

