diff options
Diffstat (limited to 'net/netfilter/x_tables.c')
-rw-r--r-- | net/netfilter/x_tables.c | 49 |
1 files changed, 43 insertions, 6 deletions
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index d9deebe..2e4d423 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -654,6 +654,31 @@ struct compat_xt_standard_target { compat_uint_t verdict; }; +static bool verdict_ok(int verdict) +{ + if (verdict > 0) + return true; + + if (verdict < 0) { + int v = -verdict - 1; + + if (verdict == XT_RETURN) + return true; + + switch (v) { + case NF_ACCEPT: return true; + case NF_DROP: return true; + case NF_QUEUE: return true; + default: + break; + } + + return false; + } + + return false; +} + int xt_compat_check_entry_offsets(const void *base, const char *elems, unsigned int target_offset, unsigned int next_offset) @@ -675,9 +700,15 @@ int xt_compat_check_entry_offsets(const void *base, const char *elems, if (target_offset + t->u.target_size > next_offset) return -EINVAL; - if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 && - COMPAT_XT_ALIGN(target_offset + sizeof(struct compat_xt_standard_target)) != next_offset) - return -EINVAL; + if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0) { + const struct compat_xt_standard_target *st = (const void *)t; + + if (COMPAT_XT_ALIGN(target_offset + sizeof(*st)) != next_offset) + return -EINVAL; + + if (!verdict_ok(st->verdict)) + return -EINVAL; + } /* compat_xt_entry match has less strict alignment requirements, * otherwise they are identical. In case of padding differences @@ -757,9 +788,15 @@ int xt_check_entry_offsets(const void *base, if (target_offset + t->u.target_size > next_offset) return -EINVAL; - if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 && - XT_ALIGN(target_offset + sizeof(struct xt_standard_target)) != next_offset) - return -EINVAL; + if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0) { + const struct xt_standard_target *st = (const void *)t; + + if (XT_ALIGN(target_offset + sizeof(*st)) != next_offset) + return -EINVAL; + + if (!verdict_ok(st->verdict)) + return -EINVAL; + } return xt_check_entry_match(elems, base + target_offset, __alignof__(struct xt_entry_match)); |