diff options
| author |   Li Wei <lw@cn.fujitsu.com> | 2012-07-29 16:01:30 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2012-07-29 23:18:31 -0700 |
| commit | 8253947e2cdfb14717c9212b751b7aec9ea9ef5e (patch) | |
| tree | 9089fdfff63ec45eec1cd49d74ca53b3a4096226 | |
| parent | mISDN: Bugfix only few bytes are transfered on a connection (diff) | |
| download | linux-dev-8253947e2cdfb14717c9212b751b7aec9ea9ef5e.tar.xz linux-dev-8253947e2cdfb14717c9212b751b7aec9ea9ef5e.zip | |
ipv6: fix incorrect route 'expires' value passed to userspace
When userspace use RTM_GETROUTE to dump route table, with an already
expired route entry, we always got an 'expires' value(2147157)
calculated base on INT_MAX.
The reason of this problem is in the following satement:
rt->dst.expires - jiffies < INT_MAX
gcc promoted the type of both sides of '<' to unsigned long, thus
a small negative value would be considered greater than INT_MAX.
With the help of Eric Dumazet, do the out of bound checks in
rtnl_put_cacheinfo(), _after_ conversion to clock_t.
Signed-off-by: Li Wei <lw@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/rtnetlink.c | 8 | ||||
| -rw-r--r-- | net/ipv6/route.c | 8 |
2 files changed, 8 insertions, 8 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index bc9e380f0abf..5ff949dc954f 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -625,9 +625,13 @@ int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id, .rta_id = id, }; - if (expires) - ci.rta_expires = jiffies_to_clock_t(expires); + if (expires) { + unsigned long clock; + clock = jiffies_to_clock_t(abs(expires)); + clock = min_t(unsigned long, clock, INT_MAX); + ci.rta_expires = (expires > 0) ? clock : -clock; + } return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci); } EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo); diff --git a/net/ipv6/route.c b/net/ipv6/route.c index cf02cb97bbdd..8e80fd279100 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2480,12 +2480,8 @@ static int rt6_fill_node(struct net *net, goto nla_put_failure; if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric)) goto nla_put_failure; - if (!(rt->rt6i_flags & RTF_EXPIRES)) - expires = 0; - else if (rt->dst.expires - jiffies < INT_MAX) - expires = rt->dst.expires - jiffies; - else - expires = INT_MAX; + + expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0; if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0) goto nla_put_failure; |