diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2019-02-21 11:19:41 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-02-21 09:54:35 -0800 |
| commit | 193f3685d0546b0cea20c99894aadb70098e47bf (patch) | |
| tree | 693039efcc7acddb5d6821414b54ebc7e102ab8c /net/ipv6 | |
| parent | ae3b564179bfd06f32d051b9e5d72ce4b2a07c37 (diff) | |
| download | linux-193f3685d0546b0cea20c99894aadb70098e47bf.tar.bz2 | |
ipv6: route: enforce RCU protection in rt6_update_exception_stamp_rt()
We must access rt6_info->from under RCU read lock: move the
dereference under such lock, with proper annotation.
v1 -> v2:
- avoid using multiple, racy, fetch operations for rt->from
Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/route.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 964491cf3672..2b1ed8c6fcab 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1599,15 +1599,15 @@ static int rt6_remove_exception_rt(struct rt6_info *rt) static void rt6_update_exception_stamp_rt(struct rt6_info *rt) { struct rt6_exception_bucket *bucket; - struct fib6_info *from = rt->from; struct in6_addr *src_key = NULL; struct rt6_exception *rt6_ex; - - if (!from || - !(rt->rt6i_flags & RTF_CACHE)) - return; + struct fib6_info *from; rcu_read_lock(); + from = rcu_dereference(rt->from); + if (!from || !(rt->rt6i_flags & RTF_CACHE)) + goto unlock; + bucket = rcu_dereference(from->rt6i_exception_bucket); #ifdef CONFIG_IPV6_SUBTREES @@ -1626,6 +1626,7 @@ static void rt6_update_exception_stamp_rt(struct rt6_info *rt) if (rt6_ex) rt6_ex->stamp = jiffies; +unlock: rcu_read_unlock(); } |