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author | Ulrich Weber <ulrich.weber@sophos.com> | 2013-01-02 05:24:40 +0000 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-01-04 20:03:02 +0100 |
commit | 429da4c0b1e59837ec946cdf0f04eb1899586923 (patch) | |
tree | a7b9ce4917c399fb7d67bd7e3132f70b35f536ac | |
parent | fdb184d1467f9ed5b17c553b85eb1bb72bdbf62f (diff) | |
download | linux-429da4c0b1e59837ec946cdf0f04eb1899586923.tar.gz linux-429da4c0b1e59837ec946cdf0f04eb1899586923.tar.bz2 linux-429da4c0b1e59837ec946cdf0f04eb1899586923.zip |
netfilter: ip6t_NPT: fix IPv6 NTP checksum calculation
csum16_add() has a broken carry detection, should be:
sum += sum < (__force u16)b;
Instead of fixing csum16_add, remove the custom checksum
functions and use the generic csum_add/csum_sub ones.
Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
-rw-r--r-- | net/ipv6/netfilter/ip6t_NPT.c | 33 |
1 files changed, 7 insertions, 26 deletions
diff --git a/net/ipv6/netfilter/ip6t_NPT.c b/net/ipv6/netfilter/ip6t_NPT.c index e9486915eff6..7302b0b7b642 100644 --- a/net/ipv6/netfilter/ip6t_NPT.c +++ b/net/ipv6/netfilter/ip6t_NPT.c @@ -14,42 +14,23 @@ #include <linux/netfilter_ipv6/ip6t_NPT.h> #include <linux/netfilter/x_tables.h> -static __sum16 csum16_complement(__sum16 a) -{ - return (__force __sum16)(0xffff - (__force u16)a); -} - -static __sum16 csum16_add(__sum16 a, __sum16 b) -{ - u16 sum; - - sum = (__force u16)a + (__force u16)b; - sum += (__force u16)a < (__force u16)b; - return (__force __sum16)sum; -} - -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; - __sum16 src_sum = 0, dst_sum = 0; + __wsum 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 = 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]); + 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]); } - npt->adjustment = csum16_sub(src_sum, dst_sum); + npt->adjustment = (__force __sum16) csum_sub(src_sum, dst_sum); return 0; } @@ -85,7 +66,7 @@ static bool ip6t_npt_map_pfx(const struct ip6t_npt_tginfo *npt, return false; } - sum = csum16_add((__force __sum16)addr->s6_addr16[idx], + sum = (__force __sum16) csum_add((__force __wsum)addr->s6_addr16[idx], npt->adjustment); if (sum == CSUM_MANGLED_0) sum = 0; |