From: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx> commit 63c43787d35e45562a6b5927e2edc8f4783d95b8 upstream. Since commit 1625f4529957, vti6 is broken, all input packets are dropped (LINUX_MIB_XFRMINNOSTATES is incremented). XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 is set by vti6_rcv() before calling xfrm6_rcv()/xfrm6_rcv_spi(), thus we cannot set to NULL that value in xfrm6_rcv_spi(). A new function xfrm6_rcv_tnl() that enables to pass a value to xfrm6_rcv_spi() is added, so that xfrm6_rcv() is not touched (this function is used in several handlers). CC: Alexey Kodanev <alexey.kodanev@xxxxxxxxxx> Fixes: 1625f4529957 ("net/xfrm_input: fix possible NULL deref of tunnel.ip6->parms.i_key") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx> Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/net/xfrm.h | 4 +++- net/ipv6/ip6_vti.c | 4 +--- net/ipv6/xfrm6_input.c | 16 +++++++++++----- net/ipv6/xfrm6_tunnel.c | 2 +- 4 files changed, 16 insertions(+), 10 deletions(-) --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1551,8 +1551,10 @@ int xfrm4_tunnel_deregister(struct xfrm_ void xfrm4_local_error(struct sk_buff *skb, u32 mtu); int xfrm6_extract_header(struct sk_buff *skb); int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb); -int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi); +int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi, + struct ip6_tnl *t); int xfrm6_transport_finish(struct sk_buff *skb, int async); +int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t); int xfrm6_rcv(struct sk_buff *skb); int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr, xfrm_address_t *saddr, u8 proto); --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -324,11 +324,9 @@ static int vti6_rcv(struct sk_buff *skb) goto discard; } - XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; - rcu_read_unlock(); - return xfrm6_rcv(skb); + return xfrm6_rcv_tnl(skb, t); } rcu_read_unlock(); return -EINVAL; --- a/net/ipv6/xfrm6_input.c +++ b/net/ipv6/xfrm6_input.c @@ -21,9 +21,10 @@ int xfrm6_extract_input(struct xfrm_stat return xfrm6_extract_header(skb); } -int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi) +int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi, + struct ip6_tnl *t) { - XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; XFRM_SPI_SKB_CB(skb)->family = AF_INET6; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); return xfrm_input(skb, nexthdr, spi, 0); @@ -49,13 +50,18 @@ int xfrm6_transport_finish(struct sk_buf return -1; } -int xfrm6_rcv(struct sk_buff *skb) +int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t) { return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], - 0); + 0, t); } -EXPORT_SYMBOL(xfrm6_rcv); +EXPORT_SYMBOL(xfrm6_rcv_tnl); +int xfrm6_rcv(struct sk_buff *skb) +{ + return xfrm6_rcv_tnl(skb, NULL); +} +EXPORT_SYMBOL(xfrm6_rcv); int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr, xfrm_address_t *saddr, u8 proto) { --- a/net/ipv6/xfrm6_tunnel.c +++ b/net/ipv6/xfrm6_tunnel.c @@ -239,7 +239,7 @@ static int xfrm6_tunnel_rcv(struct sk_bu __be32 spi; spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr); - return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi); + return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL); } static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,