From: Joel Granados <j.granados@xxxxxxxxxxx> This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@xxxxxxxxxxxxxxxxxxxxxx/) * Remove sentinel element from ctl_table structs. * Remove the zeroing out of an array element (to make it look like a sentinel) in sysctl_route_net_init And ipv6_route_sysctl_init. This is not longer needed and is safe after commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") added the array size to the ctl_table registration. * Remove extra sentinel element in the declaration of devinet_vars. * Removed the "-1" in __devinet_sysctl_register, sysctl_route_net_init, ipv6_sysctl_net_init and ipv4_sysctl_init_net that adjusted for having an extra empty element when looping over ctl_table arrays * Replace the for loop stop condition in __addrconf_sysctl_register that tests for procname == NULL with one that depends on array size * Removing the unprivileged user check in ipv6_route_sysctl_init is safe as it is replaced by calling ipv6_route_sysctl_table_size; introduced in commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") * Use a table_size variable to keep the value of ARRAY_SIZE Signed-off-by: Joel Granados <j.granados@xxxxxxxxxxx> --- net/ipv4/devinet.c | 5 ++--- net/ipv4/ip_fragment.c | 2 -- net/ipv4/route.c | 8 ++------ net/ipv4/sysctl_net_ipv4.c | 7 +++---- net/ipv4/xfrm4_policy.c | 1 - net/ipv6/addrconf.c | 8 +++----- net/ipv6/icmp.c | 1 - net/ipv6/reassembly.c | 2 -- net/ipv6/route.c | 5 ----- net/ipv6/sysctl_net_ipv6.c | 8 +++----- net/ipv6/xfrm6_policy.c | 1 - 11 files changed, 13 insertions(+), 35 deletions(-) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 7a437f0d4190..6195cc5be1fc 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -2515,7 +2515,7 @@ static int ipv4_doint_and_flush(struct ctl_table *ctl, int write, static struct devinet_sysctl_table { struct ctl_table_header *sysctl_header; - struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX]; + struct ctl_table devinet_vars[IPV4_DEVCONF_MAX]; } devinet_sysctl = { .devinet_vars = { DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding", @@ -2578,7 +2578,7 @@ static int __devinet_sysctl_register(struct net *net, char *dev_name, if (!t) goto out; - for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { + for (i = 0; i < ARRAY_SIZE(t->devinet_vars); i++) { t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; t->devinet_vars[i].extra1 = p; t->devinet_vars[i].extra2 = net; @@ -2652,7 +2652,6 @@ static struct ctl_table ctl_forward_entry[] = { .extra1 = &ipv4_devconf, .extra2 = &init_net, }, - { }, }; #endif diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index a4941f53b523..e308779ed77b 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -580,7 +580,6 @@ static struct ctl_table ip4_frags_ns_ctl_table[] = { .proc_handler = proc_dointvec_minmax, .extra1 = &dist_min, }, - { } }; /* secret interval has been deprecated */ @@ -593,7 +592,6 @@ static struct ctl_table ip4_frags_ctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { } }; static int __net_init ip4_frags_ns_ctl_register(struct net *net) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index c8f76f56dc16..deecfc0e5a91 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -3509,7 +3509,6 @@ static struct ctl_table ipv4_route_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { } }; static const char ipv4_route_flush_procname[] = "flush"; @@ -3543,7 +3542,6 @@ static struct ctl_table ipv4_route_netns_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { }, }; static __net_init int sysctl_route_net_init(struct net *net) @@ -3561,16 +3559,14 @@ static __net_init int sysctl_route_net_init(struct net *net) /* Don't export non-whitelisted sysctls to unprivileged users */ if (net->user_ns != &init_user_ns) { - if (tbl[0].procname != ipv4_route_flush_procname) { - tbl[0].procname = NULL; + if (tbl[0].procname != ipv4_route_flush_procname) table_size = 0; - } } /* Update the variables to point into the current struct net * except for the first element flush */ - for (i = 1; i < ARRAY_SIZE(ipv4_route_netns_table) - 1; i++) + for (i = 1; i < table_size; i++) tbl[i].data += (void *)net - (void *)&init_net; } tbl[0].extra1 = net; diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 7e4f16a7dcc1..8b12bf195004 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -575,7 +575,6 @@ static struct ctl_table ipv4_table[] = { .extra1 = &sysctl_fib_sync_mem_min, .extra2 = &sysctl_fib_sync_mem_max, }, - { } }; static struct ctl_table ipv4_net_table[] = { @@ -1502,11 +1501,11 @@ static struct ctl_table ipv4_net_table[] = { .proc_handler = proc_dou8vec_minmax, .extra1 = SYSCTL_ONE, }, - { } }; static __net_init int ipv4_sysctl_init_net(struct net *net) { + size_t table_size = ARRAY_SIZE(ipv4_net_table); struct ctl_table *table; table = ipv4_net_table; @@ -1517,7 +1516,7 @@ static __net_init int ipv4_sysctl_init_net(struct net *net) if (!table) goto err_alloc; - for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++) { + for (i = 0; i < table_size; i++) { if (table[i].data) { /* Update the variables to point into * the current struct net @@ -1533,7 +1532,7 @@ static __net_init int ipv4_sysctl_init_net(struct net *net) } net->ipv4.ipv4_hdr = register_net_sysctl_sz(net, "net/ipv4", table, - ARRAY_SIZE(ipv4_net_table)); + table_size); if (!net->ipv4.ipv4_hdr) goto err_reg; diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index c33bca2c3841..4c74fec034c5 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -152,7 +152,6 @@ static struct ctl_table xfrm4_policy_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { } }; static __net_init int xfrm4_net_sysctl_init(struct net *net) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 247bd4d8ee45..6e7e8c4f1ab6 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -7181,14 +7181,12 @@ static const struct ctl_table addrconf_sysctl[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_TWO, }, - { - /* sentinel */ - } }; static int __addrconf_sysctl_register(struct net *net, char *dev_name, struct inet6_dev *idev, struct ipv6_devconf *p) { + size_t table_size = ARRAY_SIZE(addrconf_sysctl); int i, ifindex; struct ctl_table *table; char path[sizeof("net/ipv6/conf/") + IFNAMSIZ]; @@ -7197,7 +7195,7 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name, if (!table) goto out; - for (i = 0; table[i].data; i++) { + for (i = 0; i < table_size; i++) { table[i].data += (char *)p - (char *)&ipv6_devconf; /* If one of these is already set, then it is not safe to * overwrite either of them: this makes proc_dointvec_minmax @@ -7212,7 +7210,7 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name, snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name); p->sysctl_header = register_net_sysctl_sz(net, path, table, - ARRAY_SIZE(addrconf_sysctl)); + table_size); if (!p->sysctl_header) goto free; diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 1635da07285f..91cbf8e8009f 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -1206,7 +1206,6 @@ static struct ctl_table ipv6_icmp_table_template[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, }, - { }, }; struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net) diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index acb4f119e11f..afb343cb77ac 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -436,7 +436,6 @@ static struct ctl_table ip6_frags_ns_ctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { } }; /* secret interval has been deprecated */ @@ -449,7 +448,6 @@ static struct ctl_table ip6_frags_ctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { } }; static int __net_init ip6_frags_ns_sysctl_register(struct net *net) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 1f4b935a0e57..b49137c3031b 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -6428,7 +6428,6 @@ static struct ctl_table ipv6_route_table_template[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, }, - { } }; struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) @@ -6452,10 +6451,6 @@ struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss; table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down; - - /* Don't export sysctls to unprivileged users */ - if (net->user_ns != &init_user_ns) - table[1].procname = NULL; } return table; diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c index 888676163e90..b8cbad351802 100644 --- a/net/ipv6/sysctl_net_ipv6.c +++ b/net/ipv6/sysctl_net_ipv6.c @@ -213,7 +213,6 @@ static struct ctl_table ipv6_table_template[] = { .proc_handler = proc_doulongvec_minmax, .extra2 = &ioam6_id_wide_max, }, - { } }; static struct ctl_table ipv6_rotable[] = { @@ -248,11 +247,11 @@ static struct ctl_table ipv6_rotable[] = { .proc_handler = proc_dointvec, }, #endif /* CONFIG_NETLABEL */ - { } }; static int __net_init ipv6_sysctl_net_init(struct net *net) { + size_t table_size = ARRAY_SIZE(ipv6_table_template); struct ctl_table *ipv6_table; struct ctl_table *ipv6_route_table; struct ctl_table *ipv6_icmp_table; @@ -264,7 +263,7 @@ static int __net_init ipv6_sysctl_net_init(struct net *net) if (!ipv6_table) goto out; /* Update the variables to point into the current struct net */ - for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++) + for (i = 0; i < table_size; i++) ipv6_table[i].data += (void *)net - (void *)&init_net; ipv6_route_table = ipv6_route_sysctl_init(net); @@ -276,8 +275,7 @@ static int __net_init ipv6_sysctl_net_init(struct net *net) goto out_ipv6_route_table; net->ipv6.sysctl.hdr = register_net_sysctl_sz(net, "net/ipv6", - ipv6_table, - ARRAY_SIZE(ipv6_table_template)); + ipv6_table, table_size); if (!net->ipv6.sysctl.hdr) goto out_ipv6_icmp_table; diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index 42fb6996b077..499b5f5c19fc 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -184,7 +184,6 @@ static struct ctl_table xfrm6_policy_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { } }; static int __net_init xfrm6_net_sysctl_init(struct net *net) -- 2.43.0