From: Florian Westphal fw@strlen.de
[ Upstream commit 339031bafe6b281cf2dcb8364217288b9fdab555 ]
This is a revert of 7b1957b049 ("netfilter: nf_defrag_ipv4: use net_generic infra") and a partial revert of 8b0adbe3e3 ("netfilter: nf_defrag_ipv6: use net_generic infra").
If conntrack is builtin and kernel is booted with: nf_conntrack.enable_hooks=1
.... kernel will fail to boot due to a NULL deref in nf_defrag_ipv4_enable(): Its called before the ipv4 defrag initcall is made, so net_generic() returns NULL.
To resolve this, move the user refcount back to struct net so calls to those functions are possible even before their initcalls have run.
Fixes: 7b1957b04956 ("netfilter: nf_defrag_ipv4: use net_generic infra") Fixes: 8b0adbe3e38d ("netfilter: nf_defrag_ipv6: use net_generic infra"). Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/netfilter/ipv6/nf_defrag_ipv6.h | 1 - include/net/netns/netfilter.h | 6 +++++ net/ipv4/netfilter/nf_defrag_ipv4.c | 30 +++++++-------------- net/ipv6/netfilter/nf_conntrack_reasm.c | 2 +- net/ipv6/netfilter/nf_defrag_ipv6_hooks.c | 25 +++++++---------- 5 files changed, 25 insertions(+), 39 deletions(-)
diff --git a/include/net/netfilter/ipv6/nf_defrag_ipv6.h b/include/net/netfilter/ipv6/nf_defrag_ipv6.h index 0fd8a4159662..ceadf8ba25a4 100644 --- a/include/net/netfilter/ipv6/nf_defrag_ipv6.h +++ b/include/net/netfilter/ipv6/nf_defrag_ipv6.h @@ -17,7 +17,6 @@ struct inet_frags_ctl; struct nft_ct_frag6_pernet { struct ctl_table_header *nf_frag_frags_hdr; struct fqdir *fqdir; - unsigned int users; };
#endif /* _NF_DEFRAG_IPV6_H */ diff --git a/include/net/netns/netfilter.h b/include/net/netns/netfilter.h index 15e2b13fb0c0..71343b969cd3 100644 --- a/include/net/netns/netfilter.h +++ b/include/net/netns/netfilter.h @@ -28,5 +28,11 @@ struct netns_nf { #if IS_ENABLED(CONFIG_DECNET) struct nf_hook_entries __rcu *hooks_decnet[NF_DN_NUMHOOKS]; #endif +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) + unsigned int defrag_ipv4_users; +#endif +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) + unsigned int defrag_ipv6_users; +#endif }; #endif diff --git a/net/ipv4/netfilter/nf_defrag_ipv4.c b/net/ipv4/netfilter/nf_defrag_ipv4.c index 613432a36f0a..e61ea428ea18 100644 --- a/net/ipv4/netfilter/nf_defrag_ipv4.c +++ b/net/ipv4/netfilter/nf_defrag_ipv4.c @@ -20,13 +20,8 @@ #endif #include <net/netfilter/nf_conntrack_zones.h>
-static unsigned int defrag4_pernet_id __read_mostly; static DEFINE_MUTEX(defrag4_mutex);
-struct defrag4_pernet { - unsigned int users; -}; - static int nf_ct_ipv4_gather_frags(struct net *net, struct sk_buff *skb, u_int32_t user) { @@ -111,19 +106,15 @@ static const struct nf_hook_ops ipv4_defrag_ops[] = {
static void __net_exit defrag4_net_exit(struct net *net) { - struct defrag4_pernet *nf_defrag = net_generic(net, defrag4_pernet_id); - - if (nf_defrag->users) { + if (net->nf.defrag_ipv4_users) { nf_unregister_net_hooks(net, ipv4_defrag_ops, ARRAY_SIZE(ipv4_defrag_ops)); - nf_defrag->users = 0; + net->nf.defrag_ipv4_users = 0; } }
static struct pernet_operations defrag4_net_ops = { .exit = defrag4_net_exit, - .id = &defrag4_pernet_id, - .size = sizeof(struct defrag4_pernet), };
static int __init nf_defrag_init(void) @@ -138,24 +129,23 @@ static void __exit nf_defrag_fini(void)
int nf_defrag_ipv4_enable(struct net *net) { - struct defrag4_pernet *nf_defrag = net_generic(net, defrag4_pernet_id); int err = 0;
mutex_lock(&defrag4_mutex); - if (nf_defrag->users == UINT_MAX) { + if (net->nf.defrag_ipv4_users == UINT_MAX) { err = -EOVERFLOW; goto out_unlock; }
- if (nf_defrag->users) { - nf_defrag->users++; + if (net->nf.defrag_ipv4_users) { + net->nf.defrag_ipv4_users++; goto out_unlock; }
err = nf_register_net_hooks(net, ipv4_defrag_ops, ARRAY_SIZE(ipv4_defrag_ops)); if (err == 0) - nf_defrag->users = 1; + net->nf.defrag_ipv4_users = 1;
out_unlock: mutex_unlock(&defrag4_mutex); @@ -165,12 +155,10 @@ EXPORT_SYMBOL_GPL(nf_defrag_ipv4_enable);
void nf_defrag_ipv4_disable(struct net *net) { - struct defrag4_pernet *nf_defrag = net_generic(net, defrag4_pernet_id); - mutex_lock(&defrag4_mutex); - if (nf_defrag->users) { - nf_defrag->users--; - if (nf_defrag->users == 0) + if (net->nf.defrag_ipv4_users) { + net->nf.defrag_ipv4_users--; + if (net->nf.defrag_ipv4_users == 0) nf_unregister_net_hooks(net, ipv4_defrag_ops, ARRAY_SIZE(ipv4_defrag_ops)); } diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index a0108415275f..5c47be29b9ee 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -33,7 +33,7 @@
static const char nf_frags_cache_name[] = "nf-frags";
-unsigned int nf_frag_pernet_id __read_mostly; +static unsigned int nf_frag_pernet_id __read_mostly; static struct inet_frags nf_frags;
static struct nft_ct_frag6_pernet *nf_frag_pernet(struct net *net) diff --git a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c index e8a59d8bf2ad..cb4eb1d2c620 100644 --- a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c +++ b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c @@ -25,8 +25,6 @@ #include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
-extern unsigned int nf_frag_pernet_id; - static DEFINE_MUTEX(defrag6_mutex);
static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum, @@ -91,12 +89,10 @@ static const struct nf_hook_ops ipv6_defrag_ops[] = {
static void __net_exit defrag6_net_exit(struct net *net) { - struct nft_ct_frag6_pernet *nf_frag = net_generic(net, nf_frag_pernet_id); - - if (nf_frag->users) { + if (net->nf.defrag_ipv6_users) { nf_unregister_net_hooks(net, ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops)); - nf_frag->users = 0; + net->nf.defrag_ipv6_users = 0; } }
@@ -134,24 +130,23 @@ static void __exit nf_defrag_fini(void)
int nf_defrag_ipv6_enable(struct net *net) { - struct nft_ct_frag6_pernet *nf_frag = net_generic(net, nf_frag_pernet_id); int err = 0;
mutex_lock(&defrag6_mutex); - if (nf_frag->users == UINT_MAX) { + if (net->nf.defrag_ipv6_users == UINT_MAX) { err = -EOVERFLOW; goto out_unlock; }
- if (nf_frag->users) { - nf_frag->users++; + if (net->nf.defrag_ipv6_users) { + net->nf.defrag_ipv6_users++; goto out_unlock; }
err = nf_register_net_hooks(net, ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops)); if (err == 0) - nf_frag->users = 1; + net->nf.defrag_ipv6_users = 1;
out_unlock: mutex_unlock(&defrag6_mutex); @@ -161,12 +156,10 @@ EXPORT_SYMBOL_GPL(nf_defrag_ipv6_enable);
void nf_defrag_ipv6_disable(struct net *net) { - struct nft_ct_frag6_pernet *nf_frag = net_generic(net, nf_frag_pernet_id); - mutex_lock(&defrag6_mutex); - if (nf_frag->users) { - nf_frag->users--; - if (nf_frag->users == 0) + if (net->nf.defrag_ipv6_users) { + net->nf.defrag_ipv6_users--; + if (net->nf.defrag_ipv6_users == 0) nf_unregister_net_hooks(net, ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops)); }