From: Kuniyuki Iwashima kuniyu@amazon.com
[ Upstream commit af67508ea6cbf0e4ea27f8120056fa2efce127dd ]
While reading sysctl_fb_tunnels_only_for_init_net, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: 79134e6ce2c9 ("net: do not create fallback tunnels for non-default namespaces") Signed-off-by: Kuniyuki Iwashima kuniyu@amazon.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/netdevice.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ed2d531400051..c05701f89d6dd 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -633,9 +633,14 @@ extern int sysctl_devconf_inherit_init_net; */ static inline bool net_has_fallback_tunnels(const struct net *net) { - return !IS_ENABLED(CONFIG_SYSCTL) || - !sysctl_fb_tunnels_only_for_init_net || - (net == &init_net && sysctl_fb_tunnels_only_for_init_net == 1); +#if IS_ENABLED(CONFIG_SYSCTL) + int fb_tunnels_only_for_init_net = READ_ONCE(sysctl_fb_tunnels_only_for_init_net); + + return !fb_tunnels_only_for_init_net || + (net_eq(net, &init_net) && fb_tunnels_only_for_init_net == 1); +#else + return true; +#endif }
static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)