From 205ee117d4dc4a11ac3bd9638bb9b2e839f4de9a Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 9 Sep 2015 02:57:21 +0200 Subject: [PATCH 1/4] netfilter: nf_log: don't zap all loggers on unregister like nf_log_unset, nf_log_unregister must not reset the list of loggers. Otherwise, a call to nf_log_unregister() will render loggers of other nf protocols unusable: iptables -A INPUT -j LOG modprobe nf_log_arp ; rmmod nf_log_arp iptables -A INPUT -j LOG iptables: No chain/target/match by that name Fixes: 30e0c6a6be ("netfilter: nf_log: prepare net namespace support for loggers") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_log.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c index 675d12c69e32..a5ebd7d9c472 100644 --- a/net/netfilter/nf_log.c +++ b/net/netfilter/nf_log.c @@ -107,11 +107,15 @@ EXPORT_SYMBOL(nf_log_register); void nf_log_unregister(struct nf_logger *logger) { + const struct nf_logger *log; int i; mutex_lock(&nf_log_mutex); - for (i = 0; i < NFPROTO_NUMPROTO; i++) - RCU_INIT_POINTER(loggers[i][logger->type], NULL); + for (i = 0; i < NFPROTO_NUMPROTO; i++) { + log = nft_log_dereference(loggers[i][logger->type]); + if (log == logger) + RCU_INIT_POINTER(loggers[i][logger->type], NULL); + } mutex_unlock(&nf_log_mutex); } EXPORT_SYMBOL(nf_log_unregister); From 63cdbc06b357dcb3a7104a421ee4a4550d7fadfd Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 14 Sep 2015 17:06:27 +0200 Subject: [PATCH 2/4] netfilter: bridge: fix routing of bridge frames with call-iptables=1 We can't re-use the physoutdev storage area. 1. When using NFQUEUE in PREROUTING, we attempt to bump a bogus refcnt since nf_bridge->physoutdev is garbage (ipv4/ipv6 address) 2. for same reason, we crash in physdev match in FORWARD or later if skb is routed instead of bridged. This increases nf_bridge_info to 40 bytes, but we have no other choice. Fixes: 72b1e5e4cac7 ("netfilter: bridge: reduce nf_bridge_info to 32 bytes again") Reported-by: Sander Eikelenboom Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/linux/skbuff.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2738d355cdf9..9987af080fa0 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -179,6 +179,9 @@ struct nf_bridge_info { u8 bridged_dnat:1; __u16 frag_max_size; struct net_device *physindev; + + /* always valid & non-NULL from FORWARD on, for physdev match */ + struct net_device *physoutdev; union { /* prerouting: detect dnat in orig/reply direction */ __be32 ipv4_daddr; @@ -189,9 +192,6 @@ struct nf_bridge_info { * skb is out in neigh layer. */ char neigh_header[8]; - - /* always valid & non-NULL from FORWARD on, for physdev match */ - struct net_device *physoutdev; }; }; #endif From ba378ca9c04a5fc1b2cf0f0274a9d02eb3d1bad9 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 14 Sep 2015 18:04:09 +0200 Subject: [PATCH 3/4] netfilter: nft_compat: skip family comparison in case of NFPROTO_UNSPEC Fix lookup of existing match/target structures in the corresponding list by skipping the family check if NFPROTO_UNSPEC is used. This is resulting in the allocation and insertion of one match/target structure for each use of them. So this not only bloats memory consumption but also severely affects the time to reload the ruleset from the iptables-compat utility. After this patch, iptables-compat-restore and iptables-compat take almost the same time to reload large rulesets. Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_compat.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c index 66def315eb56..9c8fab00164b 100644 --- a/net/netfilter/nft_compat.c +++ b/net/netfilter/nft_compat.c @@ -619,6 +619,13 @@ struct nft_xt { static struct nft_expr_type nft_match_type; +static bool nft_match_cmp(const struct xt_match *match, + const char *name, u32 rev, u32 family) +{ + return strcmp(match->name, name) == 0 && match->revision == rev && + (match->family == NFPROTO_UNSPEC || match->family == family); +} + static const struct nft_expr_ops * nft_match_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) @@ -626,7 +633,7 @@ nft_match_select_ops(const struct nft_ctx *ctx, struct nft_xt *nft_match; struct xt_match *match; char *mt_name; - __u32 rev, family; + u32 rev, family; if (tb[NFTA_MATCH_NAME] == NULL || tb[NFTA_MATCH_REV] == NULL || @@ -641,8 +648,7 @@ nft_match_select_ops(const struct nft_ctx *ctx, list_for_each_entry(nft_match, &nft_match_list, head) { struct xt_match *match = nft_match->ops.data; - if (strcmp(match->name, mt_name) == 0 && - match->revision == rev && match->family == family) { + if (nft_match_cmp(match, mt_name, rev, family)) { if (!try_module_get(match->me)) return ERR_PTR(-ENOENT); @@ -693,6 +699,13 @@ static LIST_HEAD(nft_target_list); static struct nft_expr_type nft_target_type; +static bool nft_target_cmp(const struct xt_target *tg, + const char *name, u32 rev, u32 family) +{ + return strcmp(tg->name, name) == 0 && tg->revision == rev && + (tg->family == NFPROTO_UNSPEC || tg->family == family); +} + static const struct nft_expr_ops * nft_target_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) @@ -700,7 +713,7 @@ nft_target_select_ops(const struct nft_ctx *ctx, struct nft_xt *nft_target; struct xt_target *target; char *tg_name; - __u32 rev, family; + u32 rev, family; if (tb[NFTA_TARGET_NAME] == NULL || tb[NFTA_TARGET_REV] == NULL || @@ -715,8 +728,7 @@ nft_target_select_ops(const struct nft_ctx *ctx, list_for_each_entry(nft_target, &nft_target_list, head) { struct xt_target *target = nft_target->ops.data; - if (strcmp(target->name, tg_name) == 0 && - target->revision == rev && target->family == family) { + if (nft_target_cmp(target, tg_name, rev, family)) { if (!try_module_get(target->me)) return ERR_PTR(-ENOENT); From ad5001cc7cdf9aaee5eb213fdee657e4a3c94776 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 17 Sep 2015 13:37:00 +0200 Subject: [PATCH 4/4] netfilter: nf_log: wait for rcu grace after logger unregistration The nf_log_unregister() function needs to call synchronize_rcu() to make sure that the objects are not dereferenced anymore on module removal. Fixes: 5962815a6a56 ("netfilter: nf_log: use an array of loggers instead of list") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_log.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c index a5ebd7d9c472..a5d41dfa9f05 100644 --- a/net/netfilter/nf_log.c +++ b/net/netfilter/nf_log.c @@ -117,6 +117,7 @@ void nf_log_unregister(struct nf_logger *logger) RCU_INIT_POINTER(loggers[i][logger->type], NULL); } mutex_unlock(&nf_log_mutex); + synchronize_rcu(); } EXPORT_SYMBOL(nf_log_unregister);