diff options
author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-08-23 10:46:57 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-08-24 13:46:58 +0100 |
commit | a5612ca10d1aa05624ebe72633e0c8c792970833 (patch) | |
tree | c684dfb70112852bc34790fed94b3cb894f52058 | |
parent | af67508ea6cbf0e4ea27f8120056fa2efce127dd (diff) | |
download | linux-a5612ca10d1aa05624ebe72633e0c8c792970833.tar.gz linux-a5612ca10d1aa05624ebe72633e0c8c792970833.tar.bz2 linux-a5612ca10d1aa05624ebe72633e0c8c792970833.zip |
net: Fix data-races around sysctl_devconf_inherit_init_net.
While reading sysctl_devconf_inherit_init_net, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: 856c395cfa63 ("net: introduce a knob to control whether to inherit devconf config")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | include/linux/netdevice.h | 9 | ||||
-rw-r--r-- | net/ipv4/devinet.c | 16 | ||||
-rw-r--r-- | net/ipv6/addrconf.c | 5 |
3 files changed, 21 insertions, 9 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 6d3a33fd0cdb..05d6f3facd5a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -650,6 +650,15 @@ static inline bool net_has_fallback_tunnels(const struct net *net) #endif } +static inline int net_inherit_devconf(void) +{ +#if IS_ENABLED(CONFIG_SYSCTL) + return READ_ONCE(sysctl_devconf_inherit_init_net); +#else + return 0; +#endif +} + static inline int netdev_queue_numa_node_read(const struct netdev_queue *q) { #if defined(CONFIG_XPS) && defined(CONFIG_NUMA) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 92b778e423df..e8b9a9202fec 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -2682,23 +2682,27 @@ static __net_init int devinet_init_net(struct net *net) #endif if (!net_eq(net, &init_net)) { - if (IS_ENABLED(CONFIG_SYSCTL) && - sysctl_devconf_inherit_init_net == 3) { + switch (net_inherit_devconf()) { + case 3: /* copy from the current netns */ memcpy(all, current->nsproxy->net_ns->ipv4.devconf_all, sizeof(ipv4_devconf)); memcpy(dflt, current->nsproxy->net_ns->ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt)); - } else if (!IS_ENABLED(CONFIG_SYSCTL) || - sysctl_devconf_inherit_init_net != 2) { - /* inherit == 0 or 1: copy from init_net */ + break; + case 0: + case 1: + /* copy from init_net */ memcpy(all, init_net.ipv4.devconf_all, sizeof(ipv4_devconf)); memcpy(dflt, init_net.ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt)); + break; + case 2: + /* use compiled values */ + break; } - /* else inherit == 2: use compiled values */ } #ifdef CONFIG_SYSCTL diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index b624e3d8c5f0..e15f64f22fa8 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -7162,9 +7162,8 @@ static int __net_init addrconf_init_net(struct net *net) if (!dflt) goto err_alloc_dflt; - if (IS_ENABLED(CONFIG_SYSCTL) && - !net_eq(net, &init_net)) { - switch (sysctl_devconf_inherit_init_net) { + if (!net_eq(net, &init_net)) { + switch (net_inherit_devconf()) { case 1: /* copy from init_net */ memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf)); |