[NET]: Fix fib_rules compatibility breakage
Based upon a patch from Patrick McHardy.
The fib_rules netlink attribute policy introduced in 2.6.19 broke
userspace compatibilty. When specifying a rule with "from all"
or "to all", iproute adds a zero byte long netlink attribute,
but the policy requires all addresses to have a size equal to
sizeof(struct in_addr)/sizeof(struct in6_addr), resulting in a
validation error.
Check attribute length of FRA_SRC/FRA_DST in the generic framework
by letting the family specific rules implementation provide the
length of an address. Report an error if address length is non
zero but no address attribute is provided. Fix actual bug by
checking address length for non-zero instead of relying on
availability of attribute.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index b837c33..c660c07 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -171,8 +171,6 @@
static struct nla_policy fib4_rule_policy[FRA_MAX+1] __read_mostly = {
FRA_GENERIC_POLICY,
- [FRA_SRC] = { .type = NLA_U32 },
- [FRA_DST] = { .type = NLA_U32 },
[FRA_FLOW] = { .type = NLA_U32 },
};
@@ -183,8 +181,7 @@
int err = -EINVAL;
struct fib4_rule *rule4 = (struct fib4_rule *) rule;
- if (frh->src_len > 32 || frh->dst_len > 32 ||
- (frh->tos & ~IPTOS_TOS_MASK))
+ if (frh->tos & ~IPTOS_TOS_MASK)
goto errout;
if (rule->table == RT_TABLE_UNSPEC) {
@@ -201,10 +198,10 @@
}
}
- if (tb[FRA_SRC])
+ if (frh->src_len)
rule4->src = nla_get_be32(tb[FRA_SRC]);
- if (tb[FRA_DST])
+ if (frh->dst_len)
rule4->dst = nla_get_be32(tb[FRA_DST]);
#ifdef CONFIG_NET_CLS_ROUTE
@@ -242,10 +239,10 @@
return 0;
#endif
- if (tb[FRA_SRC] && (rule4->src != nla_get_be32(tb[FRA_SRC])))
+ if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC])))
return 0;
- if (tb[FRA_DST] && (rule4->dst != nla_get_be32(tb[FRA_DST])))
+ if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST])))
return 0;
return 1;
@@ -309,6 +306,7 @@
static struct fib_rules_ops fib4_rules_ops = {
.family = AF_INET,
.rule_size = sizeof(struct fib4_rule),
+ .addr_size = sizeof(u32),
.action = fib4_rule_action,
.match = fib4_rule_match,
.configure = fib4_rule_configure,