Hi, Here is the signed-off patch. Signed-off-by: Jean-Michel DILLY <jm@xxxxxxxx> --- diff --git a/ip6t_NPT.c b/linux-3.8-rc4/net/ipv6/netfilter/ip6t_NPT.c index 787748b..29ef720 100644 --- a/ip6t_NPT.c +++ b/linux-3.8-rc4/net/ipv6/netfilter/ip6t_NPT.c @@ -14,24 +14,44 @@ #include <linux/netfilter_ipv6/ip6t_NPT.h> #include <linux/netfilter/x_tables.h> +static __sum16 csum16_add(__sum16 a, __sum16 b) +{ + __u16 result; + + result = (__force __u16) a + (__force __u16) b; + result += result < (__force __u16)b; + + + return (__force __sum16) result; +} + +static __sum16 csum16_complement(__sum16 a) +{ + return (__force __sum16)(0xffff - (__force u16)a); +} + +static __sum16 csum16_sub(__sum16 a, __sum16 b) +{ + return csum16_add(a, csum16_complement(b)); +} static int ip6t_npt_checkentry(const struct xt_tgchk_param *par) { struct ip6t_npt_tginfo *npt = par->targinfo; - __wsum src_sum = 0, dst_sum = 0; + __sum16 src_sum = 0, dst_sum = 0; unsigned int i; if (npt->src_pfx_len > 64 || npt->dst_pfx_len > 64) return -EINVAL; for (i = 0; i < ARRAY_SIZE(npt->src_pfx.in6.s6_addr16); i++) { - src_sum = csum_add(src_sum, - (__force __wsum)npt->src_pfx.in6.s6_addr16[i]); - dst_sum = csum_add(dst_sum, - (__force __wsum)npt->dst_pfx.in6.s6_addr16[i]); + src_sum = csum16_add(src_sum, + (__force __sum16)npt->src_pfx.in6.s6_addr16[i]); + dst_sum = csum16_add(dst_sum, + (__force __sum16)npt->dst_pfx.in6.s6_addr16[i]); } - npt->adjustment = (__force __sum16) csum_sub(src_sum, dst_sum); + npt->adjustment = csum16_sub(src_sum, dst_sum); return 0; } @@ -67,8 +87,8 @@ static bool ip6t_npt_map_pfx(const struct ip6t_npt_tginfo *npt, return false; } - sum = (__force __sum16) csum_add((__force __wsum)addr->s6_addr16[idx], - npt->adjustment); + sum = csum16_add((__force __sum16)addr->s6_addr16[idx], + npt->adjustment); if (sum == CSUM_MANGLED_0) sum = 0; *(__force __sum16 *)&addr->s6_addr16[idx] = sum; Le 24 janv. 2013 à 23:49, Florian Westphal a écrit : > Jean-Michel DILLY <jm@xxxxxxxx> wrote: >> Hi all, >> This patch doesn't work as expected. I tried with few IP and each time 0x0100 were missing. csum_add seems buggy too. >> I have reimplemented csum16s functions with the Ulrich's fix. It seems to work now. >> I'm a noob, so I guess someone will propose a better patch for this. > > We can't use csum_add after all, patch looks correct. > > Can you re-send with proper Signoff? > > [ carry detection breaks on overflow, e.g. a==1 and b=0xffff yields > 0 for csum_add (65536 < 1) and 1 for csum16_add (0 < 1) ] > -- > To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html