Subject: [PATCH net-next] net: hide the definition of dev_get_by_napi_id()

From: Jakub Kicinski <[email-masked]>
Date: Thu, 9 Jan 2025 16:49:24 -0800

There are no module callers of dev_get_by_napi_id(),
and commit d1cacd747768 ("netdev: prevent accessing NAPI instances
from another namespace") proves that getting NAPI by id
needs to be done with care. So hide dev_get_by_napi_id().

Signed-off-by: Jakub Kicinski <[email-masked]>
---
CC: [email-masked]
---
 include/linux/netdevice.h | 1 -
 net/core/dev.c            | 2 --
 net/core/dev.h            | 1 +
 net/socket.c              | 2 ++
 4 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 1812564b5204..aeb4a6cff171 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3252,7 +3252,6 @@ struct net_device *netdev_get_by_index(struct net *net, int ifindex,
 struct net_device *netdev_get_by_name(struct net *net, const char *name,
 				      netdevice_tracker *tracker, gfp_t gfp);
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
-struct net_device *dev_get_by_napi_id(unsigned int napi_id);
 void netdev_copy_name(struct net_device *dev, char *name);
 
 static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
diff --git a/net/core/dev.c b/net/core/dev.c
index 4452ca2c91ea..1a90ed8cc6cc 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -957,7 +957,6 @@ EXPORT_SYMBOL(netdev_get_by_index);
  *	its reference counter increased so the caller must be careful
  *	about locking. The caller must hold RCU lock.
  */
-
 struct net_device *dev_get_by_napi_id(unsigned int napi_id)
 {
 	struct napi_struct *napi;
@@ -971,7 +970,6 @@ struct net_device *dev_get_by_napi_id(unsigned int napi_id)
 
 	return napi ? napi->dev : NULL;
 }
-EXPORT_SYMBOL(dev_get_by_napi_id);
 
 static DEFINE_SEQLOCK(netdev_rename_lock);
 
diff --git a/net/core/dev.h b/net/core/dev.h
index 08812a025a9b..d8966847794c 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -23,6 +23,7 @@ struct sd_flow_limit {
 extern int netdev_flow_limit_table_len;
 
 struct napi_struct *netdev_napi_by_id(struct net *net, unsigned int napi_id);
+struct net_device *dev_get_by_napi_id(unsigned int napi_id);
 
 #ifdef CONFIG_PROC_FS
 int __init dev_proc_init(void);
diff --git a/net/socket.c b/net/socket.c
index 16402b8be5a7..4afe31656a2b 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -110,6 +110,8 @@
 #include <linux/ptp_clock_kernel.h>
 #include <trace/events/sock.h>
 
+#include "core/dev.h"
+
 #ifdef CONFIG_NET_RX_BUSY_POLL
 unsigned int sysctl_net_busy_read __read_mostly;
 unsigned int sysctl_net_busy_poll __read_mostly;
-- 
2.47.1