[PATCH 6.6 37/86] netfilter: replace -EEXIST with -EBUSY

Greg Kroah-Hartman
2026-02-09T14:47:14Z

From: Daniel Gomez <da.gomez@samsung.com>

[ Upstream commit 2bafeb8d2f380c3a81d98bd7b78b854b564f9cd4 ]

The -EEXIST error code is reserved by the module loading infrastructure
to indicate that a module is already loaded. When a module's init
function returns -EEXIST, userspace tools like kmod interpret this as
"module already loaded" and treat the operation as successful, returning
0 to the user even though the module initialization actually failed.

Replace -EEXIST with -EBUSY to ensure correct error reporting in the module
initialization path.

Affected modules:
* ebtable_broute ebtable_filter ebtable_nat arptable_filter
* ip6table_filter ip6table_mangle ip6table_nat ip6table_raw
* ip6table_security iptable_filter iptable_mangle iptable_nat
* iptable_raw iptable_security

Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/bridge/netfilter/ebtables.c | 2 +-
net/netfilter/nf_log.c | 4 ++--
net/netfilter/x_tables.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index ed62c1026fe93..f99e348c8f37f 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1299,7 +1299,7 @@ int ebt_register_template(const struct ebt_table *t, int (*table_init)(struct ne
list_for_each_entry(tmpl, &template_tables, list) {
if (WARN_ON_ONCE(strcmp(t->name, tmpl->name) == 0)) {
mutex_unlock(&ebt_mutex);
- return -EEXIST;
+ return -EBUSY;
}
}

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index e16f158388bbe..75c812f157e20 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -89,7 +89,7 @@ int nf_log_register(u_int8_t pf, struct nf_logger *logger)
if (pf == NFPROTO_UNSPEC) {
for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++) {
if (rcu_access_pointer(loggers[i][logger->type])) {
- ret = -EEXIST;
+ ret = -EBUSY;
goto unlock;
}
}
@@ -97,7 +97,7 @@ int nf_log_register(u_int8_t pf, struct nf_logger *logger)
rcu_assign_pointer(loggers[i][logger->type], logger);
} else {
if (rcu_access_pointer(loggers[pf][logger->type])) {
- ret = -EEXIST;
+ ret = -EBUSY;
goto unlock;
}
rcu_assign_pointer(loggers[pf][logger->type], logger);
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index e50c23b9c9c41..d892afc9a1acc 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1761,7 +1761,7 @@ EXPORT_SYMBOL_GPL(xt_hook_ops_alloc);
int xt_register_template(const struct xt_table *table,
int (*table_init)(struct net *net))
{
- int ret = -EEXIST, af = table->af;
+ int ret = -EBUSY, af = table->af;
struct xt_template *t;

mutex_lock(&xt[af].mutex);
--
2.51.0