From 9b3eb54106cf6acd03f07cf0ab01c13676a226c2 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Wed, 3 May 2017 16:43:19 +0200 Subject: xfrm: fix stack access out of bounds with CONFIG_XFRM_SUB_POLICY When CONFIG_XFRM_SUB_POLICY=y, xfrm_dst stores a copy of the flowi for that dst. Unfortunately, the code that allocates and fills this copy doesn't care about what type of flowi (flowi, flowi4, flowi6) gets passed. In multiple code paths (from raw_sendmsg, from TCP when replying to a FIN, in vxlan, geneve, and gre), the flowi that gets passed to xfrm is actually an on-stack flowi4, so we end up reading stuff from the stack past the end of the flowi4 struct. Since xfrm_dst->origin isn't used anywhere following commit ca116922afa8 ("xfrm: Eliminate "fl" and "pol" args to xfrm_bundle_ok()."), just get rid of it. xfrm_dst->partner isn't used either, so get rid of that too. Fixes: 9d6ec938019c ("ipv4: Use flowi4 in public route lookup interfaces.") Signed-off-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- include/net/xfrm.h | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'include/net') diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 6793a30c66b1..7e7e2b0d2915 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -979,10 +979,6 @@ struct xfrm_dst { struct flow_cache_object flo; struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; int num_pols, num_xfrms; -#ifdef CONFIG_XFRM_SUB_POLICY - struct flowi *origin; - struct xfrm_selector *partner; -#endif u32 xfrm_genid; u32 policy_genid; u32 route_mtu_cached; @@ -998,12 +994,6 @@ static inline void xfrm_dst_destroy(struct xfrm_dst *xdst) dst_release(xdst->route); if (likely(xdst->u.dst.xfrm)) xfrm_state_put(xdst->u.dst.xfrm); -#ifdef CONFIG_XFRM_SUB_POLICY - kfree(xdst->origin); - xdst->origin = NULL; - kfree(xdst->partner); - xdst->partner = NULL; -#endif } #endif -- cgit v1.3-18-gd494 From 3aa4266405a6c2e03eb0ff12d7c573d3d903da4c Mon Sep 17 00:00:00 2001 From: Or Gerlitz Date: Wed, 10 May 2017 13:48:41 +0300 Subject: net/sched: act_csum: Add accessors for offloading drivers Add the accessors for realizing if this is a csum action, and for which fields checksum is needed. Signed-off-by: Or Gerlitz Reviewed-by: Paul Blakey Signed-off-by: Saeed Mahameed --- include/net/tc_act/tc_csum.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/net') diff --git a/include/net/tc_act/tc_csum.h b/include/net/tc_act/tc_csum.h index f31fb6331a53..3248beaf16b0 100644 --- a/include/net/tc_act/tc_csum.h +++ b/include/net/tc_act/tc_csum.h @@ -3,6 +3,7 @@ #include #include +#include struct tcf_csum { struct tc_action common; @@ -11,4 +12,18 @@ struct tcf_csum { }; #define to_tcf_csum(a) ((struct tcf_csum *)a) +static inline bool is_tcf_csum(const struct tc_action *a) +{ +#ifdef CONFIG_NET_CLS_ACT + if (a->ops && a->ops->type == TCA_ACT_CSUM) + return true; +#endif + return false; +} + +static inline u32 tcf_csum_update_flags(const struct tc_action *a) +{ + return to_tcf_csum(a)->update_flags; +} + #endif /* __NET_TC_CSUM_H */ -- cgit v1.3-18-gd494 From 3fb07daff8e99243366a081e5129560734de4ada Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 25 May 2017 14:27:35 -0700 Subject: ipv4: add reference counting to metrics Andrey Konovalov reported crashes in ipv4_mtu() I could reproduce the issue with KASAN kernels, between 10.246.7.151 and 10.246.7.152 : 1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 & 2) At the same time run following loop : while : do ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 done Cong Wang attempted to add back rt->fi in commit 82486aa6f1b9 ("ipv4: restore rt->fi for reference counting") but this proved to add some issues that were complex to solve. Instead, I suggested to add a refcount to the metrics themselves, being a standalone object (in particular, no reference to other objects) I tried to make this patch as small as possible to ease its backport, instead of being super clean. Note that we believe that only ipv4 dst need to take care of the metric refcount. But if this is wrong, this patch adds the basic infrastructure to extend this to other families. Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang for his efforts on this problem. Fixes: 2860583fe840 ("ipv4: Kill rt->fi") Signed-off-by: Eric Dumazet Reported-by: Andrey Konovalov Reviewed-by: Julian Anastasov Acked-by: Cong Wang Signed-off-by: David S. Miller --- include/net/dst.h | 8 +++++++- include/net/ip_fib.h | 10 +++++----- net/core/dst.c | 23 ++++++++++++++--------- net/ipv4/fib_semantics.c | 17 ++++++++++------- net/ipv4/route.c | 10 +++++++++- 5 files changed, 45 insertions(+), 23 deletions(-) (limited to 'include/net') diff --git a/include/net/dst.h b/include/net/dst.h index 049af33da3b6..cfc043784166 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -107,10 +107,16 @@ struct dst_entry { }; }; +struct dst_metrics { + u32 metrics[RTAX_MAX]; + atomic_t refcnt; +}; +extern const struct dst_metrics dst_default_metrics; + u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old); -extern const u32 dst_default_metrics[]; #define DST_METRICS_READ_ONLY 0x1UL +#define DST_METRICS_REFCOUNTED 0x2UL #define DST_METRICS_FLAGS 0x3UL #define __DST_METRICS_PTR(Y) \ ((u32 *)((Y) & ~DST_METRICS_FLAGS)) diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 6692c5758b33..f7f6aa789c61 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -114,11 +114,11 @@ struct fib_info { __be32 fib_prefsrc; u32 fib_tb_id; u32 fib_priority; - u32 *fib_metrics; -#define fib_mtu fib_metrics[RTAX_MTU-1] -#define fib_window fib_metrics[RTAX_WINDOW-1] -#define fib_rtt fib_metrics[RTAX_RTT-1] -#define fib_advmss fib_metrics[RTAX_ADVMSS-1] + struct dst_metrics *fib_metrics; +#define fib_mtu fib_metrics->metrics[RTAX_MTU-1] +#define fib_window fib_metrics->metrics[RTAX_WINDOW-1] +#define fib_rtt fib_metrics->metrics[RTAX_RTT-1] +#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1] int fib_nhs; #ifdef CONFIG_IP_ROUTE_MULTIPATH int fib_weight; diff --git a/net/core/dst.c b/net/core/dst.c index 960e503b5a52..6192f11beec9 100644 --- a/net/core/dst.c +++ b/net/core/dst.c @@ -151,13 +151,13 @@ int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb) } EXPORT_SYMBOL(dst_discard_out); -const u32 dst_default_metrics[RTAX_MAX + 1] = { +const struct dst_metrics dst_default_metrics = { /* This initializer is needed to force linker to place this variable * into const section. Otherwise it might end into bss section. * We really want to avoid false sharing on this variable, and catch * any writes on it. */ - [RTAX_MAX] = 0xdeadbeef, + .refcnt = ATOMIC_INIT(1), }; void dst_init(struct dst_entry *dst, struct dst_ops *ops, @@ -169,7 +169,7 @@ void dst_init(struct dst_entry *dst, struct dst_ops *ops, if (dev) dev_hold(dev); dst->ops = ops; - dst_init_metrics(dst, dst_default_metrics, true); + dst_init_metrics(dst, dst_default_metrics.metrics, true); dst->expires = 0UL; dst->path = dst; dst->from = NULL; @@ -314,25 +314,30 @@ EXPORT_SYMBOL(dst_release); u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old) { - u32 *p = kmalloc(sizeof(u32) * RTAX_MAX, GFP_ATOMIC); + struct dst_metrics *p = kmalloc(sizeof(*p), GFP_ATOMIC); if (p) { - u32 *old_p = __DST_METRICS_PTR(old); + struct dst_metrics *old_p = (struct dst_metrics *)__DST_METRICS_PTR(old); unsigned long prev, new; - memcpy(p, old_p, sizeof(u32) * RTAX_MAX); + atomic_set(&p->refcnt, 1); + memcpy(p->metrics, old_p->metrics, sizeof(p->metrics)); new = (unsigned long) p; prev = cmpxchg(&dst->_metrics, old, new); if (prev != old) { kfree(p); - p = __DST_METRICS_PTR(prev); + p = (struct dst_metrics *)__DST_METRICS_PTR(prev); if (prev & DST_METRICS_READ_ONLY) p = NULL; + } else if (prev & DST_METRICS_REFCOUNTED) { + if (atomic_dec_and_test(&old_p->refcnt)) + kfree(old_p); } } - return p; + BUILD_BUG_ON(offsetof(struct dst_metrics, metrics) != 0); + return (u32 *)p; } EXPORT_SYMBOL(dst_cow_metrics_generic); @@ -341,7 +346,7 @@ void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old) { unsigned long prev, new; - new = ((unsigned long) dst_default_metrics) | DST_METRICS_READ_ONLY; + new = ((unsigned long) &dst_default_metrics) | DST_METRICS_READ_ONLY; prev = cmpxchg(&dst->_metrics, old, new); if (prev == old) kfree(__DST_METRICS_PTR(old)); diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index da449ddb8cc1..ad9ad4aab5da 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -203,6 +203,7 @@ static void rt_fibinfo_free_cpus(struct rtable __rcu * __percpu *rtp) static void free_fib_info_rcu(struct rcu_head *head) { struct fib_info *fi = container_of(head, struct fib_info, rcu); + struct dst_metrics *m; change_nexthops(fi) { if (nexthop_nh->nh_dev) @@ -213,8 +214,9 @@ static void free_fib_info_rcu(struct rcu_head *head) rt_fibinfo_free(&nexthop_nh->nh_rth_input); } endfor_nexthops(fi); - if (fi->fib_metrics != (u32 *) dst_default_metrics) - kfree(fi->fib_metrics); + m = fi->fib_metrics; + if (m != &dst_default_metrics && atomic_dec_and_test(&m->refcnt)) + kfree(m); kfree(fi); } @@ -971,11 +973,11 @@ fib_convert_metrics(struct fib_info *fi, const struct fib_config *cfg) val = 255; if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) return -EINVAL; - fi->fib_metrics[type - 1] = val; + fi->fib_metrics->metrics[type - 1] = val; } if (ecn_ca) - fi->fib_metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA; + fi->fib_metrics->metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA; return 0; } @@ -1033,11 +1035,12 @@ struct fib_info *fib_create_info(struct fib_config *cfg) goto failure; fib_info_cnt++; if (cfg->fc_mx) { - fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); + fi->fib_metrics = kzalloc(sizeof(*fi->fib_metrics), GFP_KERNEL); if (!fi->fib_metrics) goto failure; + atomic_set(&fi->fib_metrics->refcnt, 1); } else - fi->fib_metrics = (u32 *) dst_default_metrics; + fi->fib_metrics = (struct dst_metrics *)&dst_default_metrics; fi->fib_net = net; fi->fib_protocol = cfg->fc_protocol; @@ -1238,7 +1241,7 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, if (fi->fib_priority && nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority)) goto nla_put_failure; - if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) + if (rtnetlink_put_metrics(skb, fi->fib_metrics->metrics) < 0) goto nla_put_failure; if (fi->fib_prefsrc && diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 655d9eebe43e..6883b3d4ba8f 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1385,8 +1385,12 @@ static void rt_add_uncached_list(struct rtable *rt) static void ipv4_dst_destroy(struct dst_entry *dst) { + struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); struct rtable *rt = (struct rtable *) dst; + if (p != &dst_default_metrics && atomic_dec_and_test(&p->refcnt)) + kfree(p); + if (!list_empty(&rt->rt_uncached)) { struct uncached_list *ul = rt->rt_uncached_list; @@ -1438,7 +1442,11 @@ static void rt_set_nexthop(struct rtable *rt, __be32 daddr, rt->rt_gateway = nh->nh_gw; rt->rt_uses_gateway = 1; } - dst_init_metrics(&rt->dst, fi->fib_metrics, true); + dst_init_metrics(&rt->dst, fi->fib_metrics->metrics, true); + if (fi->fib_metrics != &dst_default_metrics) { + rt->dst._metrics |= DST_METRICS_REFCOUNTED; + atomic_inc(&fi->fib_metrics->refcnt); + } #ifdef CONFIG_IP_ROUTE_CLASSID rt->dst.tclassid = nh->nh_tclassid; #endif -- cgit v1.3-18-gd494