From 47a6959fa331fe892a4fc3b48ca08e92045c6bda Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 26 Apr 2021 12:14:40 +0200 Subject: netfilter: allow to turn off xtables compat layer The compat layer needs to parse untrusted input (the ruleset) to translate it to a 64bit compatible format. We had a number of bugs in this department in the past, so allow users to turn this feature off. Add CONFIG_NETFILTER_XTABLES_COMPAT kconfig knob and make it default to y to keep existing behaviour. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/bridge/netfilter/ebt_limit.c | 4 ++-- net/bridge/netfilter/ebt_mark.c | 4 ++-- net/bridge/netfilter/ebt_mark_m.c | 4 ++-- net/bridge/netfilter/ebtables.c | 12 ++++++------ net/ipv4/netfilter/arp_tables.c | 16 ++++++++-------- net/ipv4/netfilter/ip_tables.c | 16 ++++++++-------- net/ipv4/netfilter/ipt_CLUSTERIP.c | 8 ++++---- net/ipv6/netfilter/ip6_tables.c | 16 ++++++++-------- net/netfilter/Kconfig | 10 ++++++++++ net/netfilter/x_tables.c | 16 ++++++++-------- net/netfilter/xt_limit.c | 6 +++--- 11 files changed, 61 insertions(+), 51 deletions(-) (limited to 'net') diff --git a/net/bridge/netfilter/ebt_limit.c b/net/bridge/netfilter/ebt_limit.c index fa199556e122..e16183bd1bb8 100644 --- a/net/bridge/netfilter/ebt_limit.c +++ b/net/bridge/netfilter/ebt_limit.c @@ -87,7 +87,7 @@ static int ebt_limit_mt_check(const struct xt_mtchk_param *par) } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT /* * no conversion function needed -- * only avg/burst have meaningful values in userspace. @@ -107,7 +107,7 @@ static struct xt_match ebt_limit_mt_reg __read_mostly = { .checkentry = ebt_limit_mt_check, .matchsize = sizeof(struct ebt_limit_info), .usersize = offsetof(struct ebt_limit_info, prev), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(struct ebt_compat_limit_info), #endif .me = THIS_MODULE, diff --git a/net/bridge/netfilter/ebt_mark.c b/net/bridge/netfilter/ebt_mark.c index 21fd3d3d77f6..8cf653c72fd8 100644 --- a/net/bridge/netfilter/ebt_mark.c +++ b/net/bridge/netfilter/ebt_mark.c @@ -53,7 +53,7 @@ static int ebt_mark_tg_check(const struct xt_tgchk_param *par) return -EINVAL; return 0; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_ebt_mark_t_info { compat_ulong_t mark; compat_uint_t target; @@ -87,7 +87,7 @@ static struct xt_target ebt_mark_tg_reg __read_mostly = { .target = ebt_mark_tg, .checkentry = ebt_mark_tg_check, .targetsize = sizeof(struct ebt_mark_t_info), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(struct compat_ebt_mark_t_info), .compat_from_user = mark_tg_compat_from_user, .compat_to_user = mark_tg_compat_to_user, diff --git a/net/bridge/netfilter/ebt_mark_m.c b/net/bridge/netfilter/ebt_mark_m.c index 81fb59dec499..5872e73c741e 100644 --- a/net/bridge/netfilter/ebt_mark_m.c +++ b/net/bridge/netfilter/ebt_mark_m.c @@ -37,7 +37,7 @@ static int ebt_mark_mt_check(const struct xt_mtchk_param *par) } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_ebt_mark_m_info { compat_ulong_t mark, mask; uint8_t invert, bitmask; @@ -75,7 +75,7 @@ static struct xt_match ebt_mark_mt_reg __read_mostly = { .match = ebt_mark_mt, .checkentry = ebt_mark_mt_check, .matchsize = sizeof(struct ebt_mark_m_info), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(struct compat_ebt_mark_m_info), .compat_from_user = mark_mt_compat_from_user, .compat_to_user = mark_mt_compat_to_user, diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index a04596bb2a6e..f022deb3721e 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -47,7 +47,7 @@ struct ebt_pernet { static unsigned int ebt_pernet_id __read_mostly; static DEFINE_MUTEX(ebt_mutex); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT static void ebt_standard_compat_from_user(void *dst, const void *src) { int v = *(compat_int_t *)src; @@ -73,7 +73,7 @@ static struct xt_target ebt_standard_target = { .revision = 0, .family = NFPROTO_BRIDGE, .targetsize = sizeof(int), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(compat_int_t), .compat_from_user = ebt_standard_compat_from_user, .compat_to_user = ebt_standard_compat_to_user, @@ -1502,7 +1502,7 @@ static int copy_everything_to_user(struct ebt_table *t, void __user *user, ebt_entry_to_user, entries, tmp.entries); } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT /* 32 bit-userspace compatibility definitions. */ struct compat_ebt_replace { char name[EBT_TABLE_MAXNAMELEN]; @@ -2367,7 +2367,7 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT /* try real handler in case userland supplied needed padding */ if (in_compat_syscall() && ((cmd != EBT_SO_GET_INFO && cmd != EBT_SO_GET_INIT_INFO) || @@ -2434,7 +2434,7 @@ static int do_ebt_set_ctl(struct sock *sk, int cmd, sockptr_t arg, switch (cmd) { case EBT_SO_SET_ENTRIES: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_do_replace(net, arg, len); else @@ -2442,7 +2442,7 @@ static int do_ebt_set_ctl(struct sock *sk, int cmd, sockptr_t arg, ret = do_replace(net, arg, len); break; case EBT_SO_SET_COUNTERS: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_update_counters(net, arg, len); else diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index b1bb6a7e2dd7..cf20316094d0 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -713,7 +713,7 @@ static int copy_entries_to_user(unsigned int total_size, return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT static void compat_standard_from_user(void *dst, const void *src) { int v = *(compat_int_t *)src; @@ -800,7 +800,7 @@ static int get_info(struct net *net, void __user *user, const int *len) return -EFAULT; name[XT_TABLE_MAXNAMELEN-1] = '\0'; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_lock(NFPROTO_ARP); #endif @@ -808,7 +808,7 @@ static int get_info(struct net *net, void __user *user, const int *len) if (!IS_ERR(t)) { struct arpt_getinfo info; const struct xt_table_info *private = t->private; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct xt_table_info tmp; if (in_compat_syscall()) { @@ -835,7 +835,7 @@ static int get_info(struct net *net, void __user *user, const int *len) module_put(t->me); } else ret = PTR_ERR(t); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_unlock(NFPROTO_ARP); #endif @@ -1044,7 +1044,7 @@ static int do_add_counters(struct net *net, sockptr_t arg, unsigned int len) return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_arpt_replace { char name[XT_TABLE_MAXNAMELEN]; u32 valid_hooks; @@ -1412,7 +1412,7 @@ static int do_arpt_set_ctl(struct sock *sk, int cmd, sockptr_t arg, switch (cmd) { case ARPT_SO_SET_REPLACE: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_do_replace(sock_net(sk), arg, len); else @@ -1444,7 +1444,7 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len break; case ARPT_SO_GET_ENTRIES: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_get_entries(sock_net(sk), user, len); else @@ -1580,7 +1580,7 @@ static struct xt_target arpt_builtin_tg[] __read_mostly = { .name = XT_STANDARD_TARGET, .targetsize = sizeof(int), .family = NFPROTO_ARP, -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(compat_int_t), .compat_from_user = compat_standard_from_user, .compat_to_user = compat_standard_to_user, diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index d6caaed5dd45..13acb687c19a 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -868,7 +868,7 @@ copy_entries_to_user(unsigned int total_size, return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT static void compat_standard_from_user(void *dst, const void *src) { int v = *(compat_int_t *)src; @@ -957,7 +957,7 @@ static int get_info(struct net *net, void __user *user, const int *len) return -EFAULT; name[XT_TABLE_MAXNAMELEN-1] = '\0'; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_lock(AF_INET); #endif @@ -965,7 +965,7 @@ static int get_info(struct net *net, void __user *user, const int *len) if (!IS_ERR(t)) { struct ipt_getinfo info; const struct xt_table_info *private = t->private; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct xt_table_info tmp; if (in_compat_syscall()) { @@ -993,7 +993,7 @@ static int get_info(struct net *net, void __user *user, const int *len) module_put(t->me); } else ret = PTR_ERR(t); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_unlock(AF_INET); #endif @@ -1199,7 +1199,7 @@ do_add_counters(struct net *net, sockptr_t arg, unsigned int len) return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_ipt_replace { char name[XT_TABLE_MAXNAMELEN]; u32 valid_hooks; @@ -1621,7 +1621,7 @@ do_ipt_set_ctl(struct sock *sk, int cmd, sockptr_t arg, unsigned int len) switch (cmd) { case IPT_SO_SET_REPLACE: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_do_replace(sock_net(sk), arg, len); else @@ -1654,7 +1654,7 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) break; case IPT_SO_GET_ENTRIES: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_get_entries(sock_net(sk), user, len); else @@ -1846,7 +1846,7 @@ static struct xt_target ipt_builtin_tg[] __read_mostly = { .name = XT_STANDARD_TARGET, .targetsize = sizeof(int), .family = NFPROTO_IPV4, -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(compat_int_t), .compat_from_user = compat_standard_from_user, .compat_to_user = compat_standard_to_user, diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c index a8b980ad11d4..8f7ca67475b7 100644 --- a/net/ipv4/netfilter/ipt_CLUSTERIP.c +++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c @@ -541,7 +541,7 @@ static void clusterip_tg_destroy(const struct xt_tgdtor_param *par) nf_ct_netns_put(par->net, par->family); } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_ipt_clusterip_tgt_info { u_int32_t flags; @@ -553,7 +553,7 @@ struct compat_ipt_clusterip_tgt_info u_int32_t hash_initval; compat_uptr_t config; }; -#endif /* CONFIG_COMPAT */ +#endif /* CONFIG_NETFILTER_XTABLES_COMPAT */ static struct xt_target clusterip_tg_reg __read_mostly = { .name = "CLUSTERIP", @@ -563,9 +563,9 @@ static struct xt_target clusterip_tg_reg __read_mostly = { .destroy = clusterip_tg_destroy, .targetsize = sizeof(struct ipt_clusterip_tgt_info), .usersize = offsetof(struct ipt_clusterip_tgt_info, config), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(struct compat_ipt_clusterip_tgt_info), -#endif /* CONFIG_COMPAT */ +#endif /* CONFIG_NETFILTER_XTABLES_COMPAT */ .me = THIS_MODULE }; diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index e763716ffa25..e810a23baf99 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -884,7 +884,7 @@ copy_entries_to_user(unsigned int total_size, return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT static void compat_standard_from_user(void *dst, const void *src) { int v = *(compat_int_t *)src; @@ -973,7 +973,7 @@ static int get_info(struct net *net, void __user *user, const int *len) return -EFAULT; name[XT_TABLE_MAXNAMELEN-1] = '\0'; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_lock(AF_INET6); #endif @@ -981,7 +981,7 @@ static int get_info(struct net *net, void __user *user, const int *len) if (!IS_ERR(t)) { struct ip6t_getinfo info; const struct xt_table_info *private = t->private; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct xt_table_info tmp; if (in_compat_syscall()) { @@ -1009,7 +1009,7 @@ static int get_info(struct net *net, void __user *user, const int *len) module_put(t->me); } else ret = PTR_ERR(t); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) xt_compat_unlock(AF_INET6); #endif @@ -1215,7 +1215,7 @@ do_add_counters(struct net *net, sockptr_t arg, unsigned int len) return ret; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_ip6t_replace { char name[XT_TABLE_MAXNAMELEN]; u32 valid_hooks; @@ -1630,7 +1630,7 @@ do_ip6t_set_ctl(struct sock *sk, int cmd, sockptr_t arg, unsigned int len) switch (cmd) { case IP6T_SO_SET_REPLACE: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_do_replace(sock_net(sk), arg, len); else @@ -1663,7 +1663,7 @@ do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) break; case IP6T_SO_GET_ENTRIES: -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) ret = compat_get_entries(sock_net(sk), user, len); else @@ -1853,7 +1853,7 @@ static struct xt_target ip6t_builtin_tg[] __read_mostly = { .name = XT_STANDARD_TARGET, .targetsize = sizeof(int), .family = NFPROTO_IPV6, -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(compat_int_t), .compat_from_user = compat_standard_from_user, .compat_to_user = compat_standard_to_user, diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index fcd8682704c4..56a2531a3402 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -728,6 +728,16 @@ config NETFILTER_XTABLES if NETFILTER_XTABLES +config NETFILTER_XTABLES_COMPAT + bool "Netfilter Xtables 32bit support" + depends on COMPAT + default y + help + This option provides a translation layer to run 32bit arp,ip(6),ebtables + binaries on 64bit kernels. + + If unsure, say N. + comment "Xtables combined modules" config NETFILTER_XT_MARK diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index ef37deff8405..84e58ee501a4 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -52,7 +52,7 @@ struct xt_af { struct mutex mutex; struct list_head match; struct list_head target; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct mutex compat_mutex; struct compat_delta *compat_tab; unsigned int number; /* number of slots in compat_tab[] */ @@ -647,7 +647,7 @@ static bool error_tg_ok(unsigned int usersize, unsigned int kernsize, return usersize == kernsize && strnlen(msg, msglen) < msglen; } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta) { struct xt_af *xp = &xt[af]; @@ -850,7 +850,7 @@ int xt_compat_check_entry_offsets(const void *base, const char *elems, __alignof__(struct compat_xt_entry_match)); } EXPORT_SYMBOL(xt_compat_check_entry_offsets); -#endif /* CONFIG_COMPAT */ +#endif /* CONFIG_NETFILTER_XTABLES_COMPAT */ /** * xt_check_entry_offsets - validate arp/ip/ip6t_entry @@ -868,7 +868,7 @@ EXPORT_SYMBOL(xt_compat_check_entry_offsets); * match structures are aligned, and that the last structure ends where * the target structure begins. * - * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version. + * Also see xt_compat_check_entry_offsets for CONFIG_NETFILTER_XTABLES_COMPAT version. * * The arp/ip/ip6t_entry structure @base must have passed following tests: * - it must point to a valid memory location @@ -1059,7 +1059,7 @@ void *xt_copy_counters(sockptr_t arg, unsigned int len, void *mem; u64 size; -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT if (in_compat_syscall()) { /* structures only differ in size due to alignment */ struct compat_xt_counters_info compat_tmp; @@ -1106,7 +1106,7 @@ void *xt_copy_counters(sockptr_t arg, unsigned int len, } EXPORT_SYMBOL_GPL(xt_copy_counters); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT int xt_compat_target_offset(const struct xt_target *target) { u_int16_t csize = target->compatsize ? : target->targetsize; @@ -1293,7 +1293,7 @@ void xt_table_unlock(struct xt_table *table) } EXPORT_SYMBOL_GPL(xt_table_unlock); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT void xt_compat_lock(u_int8_t af) { mutex_lock(&xt[af].compat_mutex); @@ -1931,7 +1931,7 @@ static int __init xt_init(void) for (i = 0; i < NFPROTO_NUMPROTO; i++) { mutex_init(&xt[i].mutex); -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT mutex_init(&xt[i].compat_mutex); xt[i].compat_tab = NULL; #endif diff --git a/net/netfilter/xt_limit.c b/net/netfilter/xt_limit.c index bd1dea9c7b88..24d4afb9988d 100644 --- a/net/netfilter/xt_limit.c +++ b/net/netfilter/xt_limit.c @@ -134,7 +134,7 @@ static void limit_mt_destroy(const struct xt_mtdtor_param *par) kfree(info->master); } -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT struct compat_xt_rateinfo { u_int32_t avg; u_int32_t burst; @@ -176,7 +176,7 @@ static int limit_mt_compat_to_user(void __user *dst, const void *src) }; return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0; } -#endif /* CONFIG_COMPAT */ +#endif /* CONFIG_NETFILTER_XTABLES_COMPAT */ static struct xt_match limit_mt_reg __read_mostly = { .name = "limit", @@ -186,7 +186,7 @@ static struct xt_match limit_mt_reg __read_mostly = { .checkentry = limit_mt_check, .destroy = limit_mt_destroy, .matchsize = sizeof(struct xt_rateinfo), -#ifdef CONFIG_COMPAT +#ifdef CONFIG_NETFILTER_XTABLES_COMPAT .compatsize = sizeof(struct compat_xt_rateinfo), .compat_from_user = limit_mt_compat_from_user, .compat_to_user = limit_mt_compat_to_user, -- cgit v1.2.3-70-g09d2