From b6ca8bd5a9198c70c48297390723e4e56bd6e879 Mon Sep 17 00:00:00 2001 From: David Miller Date: Tue, 28 Nov 2017 15:45:44 -0500 Subject: [PATCH] xfrm: Move child route linkage into xfrm_dst. XFRM bundle child chains look like this: xdst1 --> xdst2 --> xdst3 --> path_dst All of xdstN are xfrm_dst objects and xdst->u.dst.xfrm is non-NULL. The final child pointer in the chain, here called 'path_dst', is some other kind of route such as an ipv4 or ipv6 one. The xfrm output path pops routes, one at a time, via the child pointer, until we hit one which has a dst->xfrm pointer which is NULL. We can easily preserve the above mechanisms with child sitting only in the xfrm_dst structure. All children in the chain before we break out of the xfrm_output() loop have dst->xfrm non-NULL and are therefore xfrm_dst objects. Since we break out of the loop when we find dst->xfrm NULL, we will not try to dereference 'dst' as if it were an xfrm_dst. Signed-off-by: David S. Miller --- include/net/dst.h | 3 +-- include/net/xfrm.h | 15 ++++++++++----- net/core/dst.c | 9 ++++++--- net/core/pktgen.c | 12 ++++++------ net/netfilter/xt_policy.c | 3 ++- net/xfrm/xfrm_device.c | 2 +- 6 files changed, 26 insertions(+), 18 deletions(-) diff --git a/include/net/dst.h b/include/net/dst.h index acbb3fb89c4d..cef46207408c 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -35,7 +35,6 @@ struct sk_buff; struct dst_entry { struct net_device *dev; struct rcu_head rcu_head; - struct dst_entry *child; struct dst_ops *ops; unsigned long _metrics; unsigned long expires; @@ -89,7 +88,7 @@ struct dst_entry { * Align __refcnt to a 64 bytes alignment * (L1_CACHE_SIZE would be too much) */ - long __pad_to_align_refcnt[2]; + long __pad_to_align_refcnt[3]; #endif /* * __refcnt wants to be on a different cache line from diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 4c08eb0d46ce..0009dab61528 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -968,7 +968,7 @@ static inline bool xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_c /* A struct encoding bundle of transformations to apply to some set of flow. * - * dst->child points to the next element of bundle. + * xdst->child points to the next element of bundle. * dst->xfrm points to an instanse of transformer. * * Due to unfortunate limitations of current routing cache, which we @@ -984,6 +984,7 @@ struct xfrm_dst { struct rt6_info rt6; } u; struct dst_entry *route; + struct dst_entry *child; struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; int num_pols, num_xfrms; u32 xfrm_genid; @@ -997,8 +998,10 @@ struct xfrm_dst { static inline struct dst_entry *xfrm_dst_child(const struct dst_entry *dst) { #ifdef CONFIG_XFRM - if (dst->xfrm) - return dst->child; + if (dst->xfrm) { + struct xfrm_dst *xdst = (struct xfrm_dst *) dst; + return xdst->child; + } #endif return NULL; } @@ -1006,7 +1009,7 @@ static inline struct dst_entry *xfrm_dst_child(const struct dst_entry *dst) #ifdef CONFIG_XFRM static inline void xfrm_dst_set_child(struct xfrm_dst *xdst, struct dst_entry *child) { - xdst->u.dst.child = child; + xdst->child = child; } static inline void xfrm_dst_destroy(struct xfrm_dst *xdst) @@ -1880,12 +1883,14 @@ bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x); static inline bool xfrm_dst_offload_ok(struct dst_entry *dst) { struct xfrm_state *x = dst->xfrm; + struct xfrm_dst *xdst; if (!x || !x->type_offload) return false; + xdst = (struct xfrm_dst *) dst; if (x->xso.offload_handle && (x->xso.dev == dst->path->dev) && - !dst->child->xfrm) + !xdst->child->xfrm) return true; return false; diff --git a/net/core/dst.c b/net/core/dst.c index 6a3c21b8fc8d..5cf96179e8e0 100644 --- a/net/core/dst.c +++ b/net/core/dst.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -62,7 +63,6 @@ void dst_init(struct dst_entry *dst, struct dst_ops *ops, struct net_device *dev, int initial_ref, int initial_obsolete, unsigned short flags) { - dst->child = NULL; dst->dev = dev; if (dev) dev_hold(dev); @@ -121,8 +121,11 @@ struct dst_entry *dst_destroy(struct dst_entry * dst) smp_rmb(); #ifdef CONFIG_XFRM - if (dst->xfrm) - child = dst->child; + if (dst->xfrm) { + struct xfrm_dst *xdst = (struct xfrm_dst *) dst; + + child = xdst->child; + } #endif if (!(dst->flags & DST_NOCOUNT)) dst_entries_add(dst->ops, -1); diff --git a/net/core/pktgen.c b/net/core/pktgen.c index f95a15086225..b9ce241cd28c 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -399,7 +399,7 @@ struct pktgen_dev { __u8 ipsmode; /* IPSEC mode (config) */ __u8 ipsproto; /* IPSEC type (config) */ __u32 spi; - struct dst_entry dst; + struct xfrm_dst xdst; struct dst_ops dstops; #endif char result[512]; @@ -2609,7 +2609,7 @@ static int pktgen_output_ipsec(struct sk_buff *skb, struct pktgen_dev *pkt_dev) * supports both transport/tunnel mode + ESP/AH type. */ if ((x->props.mode == XFRM_MODE_TUNNEL) && (pkt_dev->spi != 0)) - skb->_skb_refdst = (unsigned long)&pkt_dev->dst | SKB_DST_NOREF; + skb->_skb_refdst = (unsigned long)&pkt_dev->xdst.u.dst | SKB_DST_NOREF; rcu_read_lock_bh(); err = x->outer_mode->output(x, skb); @@ -3742,10 +3742,10 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname) * performance under such circumstance. */ pkt_dev->dstops.family = AF_INET; - pkt_dev->dst.dev = pkt_dev->odev; - dst_init_metrics(&pkt_dev->dst, pktgen_dst_metrics, false); - pkt_dev->dst.child = &pkt_dev->dst; - pkt_dev->dst.ops = &pkt_dev->dstops; + pkt_dev->xdst.u.dst.dev = pkt_dev->odev; + dst_init_metrics(&pkt_dev->xdst.u.dst, pktgen_dst_metrics, false); + pkt_dev->xdst.child = &pkt_dev->xdst.u.dst; + pkt_dev->xdst.u.dst.ops = &pkt_dev->dstops; #endif return add_dev_to_thread(t, pkt_dev); diff --git a/net/netfilter/xt_policy.c b/net/netfilter/xt_policy.c index 2b4ab189bba7..5639fb03bdd9 100644 --- a/net/netfilter/xt_policy.c +++ b/net/netfilter/xt_policy.c @@ -93,7 +93,8 @@ match_policy_out(const struct sk_buff *skb, const struct xt_policy_info *info, if (dst->xfrm == NULL) return -1; - for (i = 0; dst && dst->xfrm; dst = dst->child, i++) { + for (i = 0; dst && dst->xfrm; + dst = ((struct xfrm_dst *)dst)->child, i++) { pos = strict ? i : 0; if (pos >= info->len) return 0; diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c index 30e5746085b8..c5851ddddd2a 100644 --- a/net/xfrm/xfrm_device.c +++ b/net/xfrm/xfrm_device.c @@ -121,7 +121,7 @@ bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x) return false; if ((x->xso.offload_handle && (dev == dst->path->dev)) && - !dst->child->xfrm && x->type->get_mtu) { + !xdst->child->xfrm && x->type->get_mtu) { mtu = x->type->get_mtu(x, xdst->child_mtu_cached); if (skb->len <= mtu)