path: root/include
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authorDavid S. Miller <davem@davemloft.net>2020-06-25 12:52:41 -0700
committerDavid S. Miller <davem@davemloft.net>2020-06-25 12:52:41 -0700
commitf4926d513b4c753c3e831dc619466c82ba192fed (patch)
tree2a186959e8aac7936f7ed901d111c653932127e9 /include
parentnet: bridge: enfore alignment for ethernet address (diff)
parentselftests: netfilter: add test case for conntrack helper assignment (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net, they are: 1) Unaligned atomic access in ipset, from Russell King. 2) Missing module description, from Rob Gill. 3) Patches to fix a module unload causing NULL pointer dereference in xtables, from David Wilder. For the record, I posting here his cover letter explaining the problem: A crash happened on ppc64le when running ltp network tests triggered by "rmmod iptable_mangle". See previous discussion in this thread: https://lists.openwall.net/netdev/2020/06/03/161 . In the crash I found in iptable_mangle_hook() that state->net->ipv4.iptable_mangle=NULL causing a NULL pointer dereference. net->ipv4.iptable_mangle is set to NULL in +iptable_mangle_net_exit() and called when ip_mangle modules is unloaded. A rmmod task was found running in the crash dump. A 2nd crash showed the same problem when running "rmmod iptable_filter" (net->ipv4.iptable_filter=NULL). To fix this I added .pre_exit hook in all iptable_foo.c. The pre_exit will un-register the underlying hook and exit would do the table freeing. The netns core does an unconditional +synchronize_rcu after the pre_exit hooks insuring no packets are in flight that have picked up the pointer before completing the un-register. These patches include changes for both iptables and ip6tables. We tested this fix with ltp running iptables01.sh and iptables01.sh -6 a loop for 72 hours. 4) Add a selftest for conntrack helper assignment, from Florian Westphal. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
2 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
index b394bd4f68a3..c4676d6feeff 100644
--- a/include/linux/netfilter_ipv4/ip_tables.h
+++ b/include/linux/netfilter_ipv4/ip_tables.h
@@ -25,6 +25,12 @@
int ipt_register_table(struct net *net, const struct xt_table *table,
const struct ipt_replace *repl,
const struct nf_hook_ops *ops, struct xt_table **res);
+void ipt_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+ const struct nf_hook_ops *ops);
+void ipt_unregister_table_exit(struct net *net, struct xt_table *table);
void ipt_unregister_table(struct net *net, struct xt_table *table,
const struct nf_hook_ops *ops);
diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
index 8225f7821a29..1547d5f9ae06 100644
--- a/include/linux/netfilter_ipv6/ip6_tables.h
+++ b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -29,6 +29,9 @@ int ip6t_register_table(struct net *net, const struct xt_table *table,
const struct nf_hook_ops *ops, struct xt_table **res);
void ip6t_unregister_table(struct net *net, struct xt_table *table,
const struct nf_hook_ops *ops);
+void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+ const struct nf_hook_ops *ops);
+void ip6t_unregister_table_exit(struct net *net, struct xt_table *table);
extern unsigned int ip6t_do_table(struct sk_buff *skb,
const struct nf_hook_state *state,
struct xt_table *table);