[NETFILTER]: Fix recent match jiffies wrap mismatches
Around jiffies wrap time (i.e. within first 5 mins after boot), recent match rules which contain both --seconds and --hitcount arguments experience false matches. This is because the last_pkts array is filled with zeros on creation, and when comparing 'now' to 0 (+ --seconds argument), time_before_eq thinks it has found a hit. Below patch adds a break if the packet value is zero. This has the unfortunate side effect of causing mismatches if a packet was received when jiffies really was equal to zero. The odds of that happening are slim compared to the problems caused by not adding the break however. Plus, the author used this same method just below, so it is "good enough". This fixes netfilter bugs #383 and #395. Signed-off-by: Phil Oester <kernel@linuxace.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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@ -532,6 +532,7 @@ match(const struct sk_buff *skb,
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if(info->seconds && info->hit_count) {
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if(info->seconds && info->hit_count) {
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for(pkt_count = 0, hits_found = 0; pkt_count < ip_pkt_list_tot; pkt_count++) {
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for(pkt_count = 0, hits_found = 0; pkt_count < ip_pkt_list_tot; pkt_count++) {
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if(r_list[location].last_pkts[pkt_count] == 0) break;
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if(time_before_eq(now,r_list[location].last_pkts[pkt_count]+info->seconds*HZ)) hits_found++;
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if(time_before_eq(now,r_list[location].last_pkts[pkt_count]+info->seconds*HZ)) hits_found++;
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}
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}
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if(hits_found >= info->hit_count) ans = !info->invert; else ans = info->invert;
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if(hits_found >= info->hit_count) ans = !info->invert; else ans = info->invert;
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