path: root/include
diff options
authorChangbin Du <>2021-06-11 22:29:59 +0800
committerDavid S. Miller <>2021-06-12 13:13:08 -0700
commitea6932d70e223e02fea3ae20a4feff05d7c1ea9a (patch)
treef886b7b8fd31d7f26b9a61377771688cdd856ec0 /include
parent1adb20f0d496b2c61e9aa1f4761b8d71f93d258e (diff)
net: make get_net_ns return error if NET_NS is disabled
There is a panic in socket ioctl cmd SIOCGSKNS when NET_NS is not enabled. The reason is that nsfs tries to access ns->ops but the proc_ns_operations is not implemented in this case. [7.670023] Unable to handle kernel NULL pointer dereference at virtual address 00000010 [7.670268] pgd = 32b54000 [7.670544] [00000010] *pgd=00000000 [7.671861] Internal error: Oops: 5 [#1] SMP ARM [7.672315] Modules linked in: [7.672918] CPU: 0 PID: 1 Comm: systemd Not tainted 5.13.0-rc3-00375-g6799d4f2da49 #16 [7.673309] Hardware name: Generic DT based system [7.673642] PC is at nsfs_evict+0x24/0x30 [7.674486] LR is at clear_inode+0x20/0x9c The same to tun SIOCGSKNS command. To fix this problem, we make get_net_ns() return -EINVAL when NET_NS is disabled. Meanwhile move it to right place net/core/net_namespace.c. Signed-off-by: Changbin Du <> Fixes: c62cce2caee5 ("net: add an ioctl to get a socket network namespace") Cc: Cong Wang <> Cc: Jakub Kicinski <> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Christian Brauner <> Suggested-by: Jakub Kicinski <> Acked-by: Christian Brauner <> Signed-off-by: David S. Miller <>
Diffstat (limited to 'include')
2 files changed, 7 insertions, 2 deletions
diff --git a/include/linux/socket.h b/include/linux/socket.h
index b8fc5c53ba6f..0d8e3dcb7f88 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -438,6 +438,4 @@ extern int __sys_socketpair(int family, int type, int protocol,
int __user *usockvec);
extern int __sys_shutdown_sock(struct socket *sock, int how);
extern int __sys_shutdown(int fd, int how);
-extern struct ns_common *get_net_ns(struct ns_common *ns);
#endif /* _LINUX_SOCKET_H */
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index fa5887143f0d..6412d7833d97 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -184,6 +184,8 @@ struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
void net_ns_barrier(void);
+struct ns_common *get_net_ns(struct ns_common *ns);
#else /* CONFIG_NET_NS */
#include <linux/sched.h>
#include <linux/nsproxy.h>
@@ -203,6 +205,11 @@ static inline void net_ns_get_ownership(const struct net *net,
static inline void net_ns_barrier(void) {}
+static inline struct ns_common *get_net_ns(struct ns_common *ns)
+ return ERR_PTR(-EINVAL);
#endif /* CONFIG_NET_NS */