diff options
Diffstat (limited to 'net/ipv6/netfilter/ip6t_NPT.c')
| -rw-r--r-- | net/ipv6/netfilter/ip6t_NPT.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/net/ipv6/netfilter/ip6t_NPT.c b/net/ipv6/netfilter/ip6t_NPT.c index 7302b0b7b64..83acc1405a1 100644 --- a/net/ipv6/netfilter/ip6t_NPT.c +++ b/net/ipv6/netfilter/ip6t_NPT.c @@ -9,6 +9,7 @@ #include <linux/module.h> #include <linux/skbuff.h> #include <linux/ipv6.h> +#include <net/ipv6.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv6.h> #include <linux/netfilter_ipv6/ip6t_NPT.h> @@ -18,11 +19,20 @@ 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; + struct in6_addr pfx; unsigned int i; if (npt->src_pfx_len > 64 || npt->dst_pfx_len > 64) return -EINVAL; + /* Ensure that LSB of prefix is zero */ + ipv6_addr_prefix(&pfx, &npt->src_pfx.in6, npt->src_pfx_len); + if (!ipv6_addr_equal(&pfx, &npt->src_pfx.in6)) + return -EINVAL; + ipv6_addr_prefix(&pfx, &npt->dst_pfx.in6, npt->dst_pfx_len); + if (!ipv6_addr_equal(&pfx, &npt->dst_pfx.in6)) + 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]); @@ -30,7 +40,7 @@ static int ip6t_npt_checkentry(const struct xt_tgchk_param *par) (__force __wsum)npt->dst_pfx.in6.s6_addr16[i]); } - npt->adjustment = (__force __sum16) csum_sub(src_sum, dst_sum); + npt->adjustment = ~csum_fold(csum_sub(src_sum, dst_sum)); return 0; } @@ -51,7 +61,7 @@ static bool ip6t_npt_map_pfx(const struct ip6t_npt_tginfo *npt, idx = i / 32; addr->s6_addr32[idx] &= mask; - addr->s6_addr32[idx] |= npt->dst_pfx.in6.s6_addr32[idx]; + addr->s6_addr32[idx] |= ~mask & npt->dst_pfx.in6.s6_addr32[idx]; } if (pfx_len <= 48) @@ -66,8 +76,8 @@ 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 = ~csum_fold(csum_add(csum_unfold((__force __sum16)addr->s6_addr16[idx]), + csum_unfold(npt->adjustment))); if (sum == CSUM_MANGLED_0) sum = 0; *(__force __sum16 *)&addr->s6_addr16[idx] = sum; |