From 30a2e107108c66cbcb7776b58cbcd7db223a1cc9 Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Tue, 5 Jun 2018 11:53:35 +0200 Subject: [PATCH] netfilter: ipset: Limit max timeout value Due to the negative value condition in msecs_to_jiffies(), the real max possible timeout value must be set to (UINT_MAX >> 1)/MSEC_PER_SEC. Neutron Soutmun proposed the proper fix, but an insufficient one was applied, see https://patchwork.ozlabs.org/patch/400405/. Signed-off-by: Jozsef Kadlecsik --- include/linux/netfilter/ipset/ip_set_timeout.h | 10 ++++++---- net/netfilter/xt_set.c | 8 ++++---- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/include/linux/netfilter/ipset/ip_set_timeout.h b/include/linux/netfilter/ipset/ip_set_timeout.h index 7ad8ddf9ca8a..8ce271e187b6 100644 --- a/include/linux/netfilter/ipset/ip_set_timeout.h +++ b/include/linux/netfilter/ipset/ip_set_timeout.h @@ -23,6 +23,9 @@ /* Set is defined with timeout support: timeout value may be 0 */ #define IPSET_NO_TIMEOUT UINT_MAX +/* Max timeout value, see msecs_to_jiffies() in jiffies.h */ +#define IPSET_MAX_TIMEOUT (UINT_MAX >> 1)/MSEC_PER_SEC + #define ip_set_adt_opt_timeout(opt, set) \ ((opt)->ext.timeout != IPSET_NO_TIMEOUT ? (opt)->ext.timeout : (set)->timeout) @@ -32,11 +35,10 @@ ip_set_timeout_uget(struct nlattr *tb) unsigned int timeout = ip_set_get_h32(tb); /* Normalize to fit into jiffies */ - if (timeout > UINT_MAX/MSEC_PER_SEC) - timeout = UINT_MAX/MSEC_PER_SEC; + if (timeout > IPSET_MAX_TIMEOUT) + timeout = IPSET_MAX_TIMEOUT; - /* Userspace supplied TIMEOUT parameter: adjust crazy size */ - return timeout == IPSET_NO_TIMEOUT ? IPSET_NO_TIMEOUT - 1 : timeout; + return timeout; } static inline bool diff --git a/net/netfilter/xt_set.c b/net/netfilter/xt_set.c index 07af7dbf7a30..bf2890b13212 100644 --- a/net/netfilter/xt_set.c +++ b/net/netfilter/xt_set.c @@ -372,8 +372,8 @@ set_target_v2(struct sk_buff *skb, const struct xt_action_param *par) /* Normalize to fit into jiffies */ if (add_opt.ext.timeout != IPSET_NO_TIMEOUT && - add_opt.ext.timeout > UINT_MAX / MSEC_PER_SEC) - add_opt.ext.timeout = UINT_MAX / MSEC_PER_SEC; + add_opt.ext.timeout > IPSET_MAX_TIMEOUT) + add_opt.ext.timeout = IPSET_MAX_TIMEOUT; if (info->add_set.index != IPSET_INVALID_ID) ip_set_add(info->add_set.index, skb, par, &add_opt); if (info->del_set.index != IPSET_INVALID_ID) @@ -407,8 +407,8 @@ set_target_v3(struct sk_buff *skb, const struct xt_action_param *par) /* Normalize to fit into jiffies */ if (add_opt.ext.timeout != IPSET_NO_TIMEOUT && - add_opt.ext.timeout > UINT_MAX / MSEC_PER_SEC) - add_opt.ext.timeout = UINT_MAX / MSEC_PER_SEC; + add_opt.ext.timeout > IPSET_MAX_TIMEOUT) + add_opt.ext.timeout = IPSET_MAX_TIMEOUT; if (info->add_set.index != IPSET_INVALID_ID) ip_set_add(info->add_set.index, skb, par, &add_opt); if (info->del_set.index != IPSET_INVALID_ID)