diff options
| -rw-r--r-- | net/ipv6/addrconf.c | 61 |
1 files changed, 40 insertions, 21 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index a225d5ee3c2f..c02280a4d126 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -502,29 +502,31 @@ static void addrconf_forward_change(struct net *net, __s32 newf) rcu_read_unlock(); } -static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old) +static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf) { struct net *net; + int old; + + if (!rtnl_trylock()) + return restart_syscall(); net = (struct net *)table->extra2; - if (p == &net->ipv6.devconf_dflt->forwarding) - return 0; + old = *p; + *p = newf; - if (!rtnl_trylock()) { - /* Restore the original values before restarting */ - *p = old; - return restart_syscall(); + if (p == &net->ipv6.devconf_dflt->forwarding) { + rtnl_unlock(); + return 0; } if (p == &net->ipv6.devconf_all->forwarding) { - __s32 newf = net->ipv6.devconf_all->forwarding; net->ipv6.devconf_dflt->forwarding = newf; addrconf_forward_change(net, newf); - } else if ((!*p) ^ (!old)) + } else if ((!newf) ^ (!old)) dev_forward_change((struct inet6_dev *)table->extra1); rtnl_unlock(); - if (*p) + if (newf) rt6_purge_dflt_routers(net); return 1; } @@ -4260,9 +4262,17 @@ int addrconf_sysctl_forward(ctl_table *ctl, int write, int *valp = ctl->data; int val = *valp; loff_t pos = *ppos; + ctl_table lctl; int ret; - ret = proc_dointvec(ctl, write, buffer, lenp, ppos); + /* + * ctl->data points to idev->cnf.forwarding, we should + * not modify it until we get the rtnl lock. + */ + lctl = *ctl; + lctl.data = &val; + + ret = proc_dointvec(&lctl, write, buffer, lenp, ppos); if (write) ret = addrconf_fixup_forwarding(ctl, valp, val); @@ -4300,26 +4310,27 @@ static void addrconf_disable_change(struct net *net, __s32 newf) rcu_read_unlock(); } -static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int old) +static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf) { struct net *net; + int old; + + if (!rtnl_trylock()) + return restart_syscall(); net = (struct net *)table->extra2; + old = *p; + *p = newf; - if (p == &net->ipv6.devconf_dflt->disable_ipv6) + if (p == &net->ipv6.devconf_dflt->disable_ipv6) { + rtnl_unlock(); return 0; - - if (!rtnl_trylock()) { - /* Restore the original values before restarting */ - *p = old; - return restart_syscall(); } if (p == &net->ipv6.devconf_all->disable_ipv6) { - __s32 newf = net->ipv6.devconf_all->disable_ipv6; net->ipv6.devconf_dflt->disable_ipv6 = newf; addrconf_disable_change(net, newf); - } else if ((!*p) ^ (!old)) + } else if ((!newf) ^ (!old)) dev_disable_change((struct inet6_dev *)table->extra1); rtnl_unlock(); @@ -4333,9 +4344,17 @@ int addrconf_sysctl_disable(ctl_table *ctl, int write, int *valp = ctl->data; int val = *valp; loff_t pos = *ppos; + ctl_table lctl; int ret; - ret = proc_dointvec(ctl, write, buffer, lenp, ppos); + /* + * ctl->data points to idev->cnf.disable_ipv6, we should + * not modify it until we get the rtnl lock. + */ + lctl = *ctl; + lctl.data = &val; + + ret = proc_dointvec(&lctl, write, buffer, lenp, ppos); if (write) ret = addrconf_disable_ipv6(ctl, valp, val); |