[PATCH ghak25 v2 9/9] netfilter: audit table unregister actions

From: Richard Guy Briggs
Date: Mon Jan 06 2020 - 13:56:28 EST


Audit the action of unregistering ebtables and x_tables.

See: https://github.com/linux-audit/audit-kernel/issues/44
Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
kernel/auditsc.c | 3 ++-
net/bridge/netfilter/ebtables.c | 3 +++
net/netfilter/x_tables.c | 4 +++-
3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 999ac184246b..2644130a9e66 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2557,7 +2557,8 @@ void __audit_nf_cfg(const char *name, u8 af, int nentries, int op)
return; /* audit_panic or being filtered */
audit_log_format(ab, "table=%s family=%u entries=%u op=%s",
name, af, nentries,
- op ? "replace" : "register");
+ op == 1 ? "replace" :
+ (op ? "unregister" : "register"));
audit_log_end(ab);
}
EXPORT_SYMBOL_GPL(__audit_nf_cfg);
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index baff2f05af43..3dd4eb5b13fd 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1126,6 +1126,9 @@ static void __ebt_unregister_table(struct net *net, struct ebt_table *table)
mutex_lock(&ebt_mutex);
list_del(&table->list);
mutex_unlock(&ebt_mutex);
+ if (audit_enabled)
+ audit_nf_cfg(table->name, AF_BRIDGE, table->private->nentries,
+ 2);
EBT_ENTRY_ITERATE(table->private->entries, table->private->entries_size,
ebt_cleanup_entry, net, NULL);
if (table->private->nentries)
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 4ae4f7bf8946..e4852a0cb62f 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1403,7 +1403,7 @@ struct xt_table_info *xt_replace_table(struct xt_table *table,

if (audit_enabled)
audit_nf_cfg(table->name, table->af, private->number,
- private->number);
+ !!private->number);

return private;
}
@@ -1466,6 +1466,8 @@ void *xt_unregister_table(struct xt_table *table)
private = table->private;
list_del(&table->list);
mutex_unlock(&xt[table->af].mutex);
+ if (audit_enabled)
+ audit_nf_cfg(table->name, table->af, private->number, 2);
kfree(table);

return private;
--
1.8.3.1