[PATCH ghak25 v3 2/3] netfilter: add audit table unregister actions

From: Richard Guy Briggs
Date: Tue Mar 17 2020 - 17:31:39 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>
---
include/linux/audit.h | 1 +
kernel/auditsc.c | 5 +++--
net/bridge/netfilter/ebtables.c | 2 ++
net/netfilter/x_tables.c | 2 ++
4 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index f4aed2b9be8d..17427c41cc29 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -97,6 +97,7 @@ struct audit_ntp_data {
enum audit_nfcfgop {
AUDIT_XT_OP_REGISTER,
AUDIT_XT_OP_REPLACE,
+ AUDIT_XT_OP_UNREGISTER,
};

extern int is_audit_feature_set(int which);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index f4e342125dd9..dbb056feccb9 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -136,8 +136,9 @@ struct audit_nfcfgop_tab {
};

const struct audit_nfcfgop_tab audit_nfcfgs[] = {
- { AUDIT_XT_OP_REGISTER, "register" },
- { AUDIT_XT_OP_REPLACE, "replace" },
+ { AUDIT_XT_OP_REGISTER, "register" },
+ { AUDIT_XT_OP_REPLACE, "replace" },
+ { AUDIT_XT_OP_UNREGISTER, "unregister" },
};

static int audit_match_perm(struct audit_context *ctx, int mask)
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 55f9409c3ee0..b3a2e6ea516c 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1124,6 +1124,8 @@ static void __ebt_unregister_table(struct net *net, struct ebt_table *table)
mutex_lock(&ebt_mutex);
list_del(&table->list);
mutex_unlock(&ebt_mutex);
+ audit_log_nfcfg(table->name, AF_BRIDGE, table->private->nentries,
+ AUDIT_XT_OP_UNREGISTER);
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 db5cbcf43748..e43720a7783b 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1472,6 +1472,8 @@ void *xt_unregister_table(struct xt_table *table)
private = table->private;
list_del(&table->list);
mutex_unlock(&xt[table->af].mutex);
+ audit_log_nfcfg(table->name, table->af, private->number,
+ AUDIT_XT_OP_UNREGISTER);
kfree(table);

return private;
--
1.8.3.1