ipv4: Fix nexthop exception hash computation.

Need to mask it with (FNHE_HASH_SIZE - 1).

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 4 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index a5bd0b4acc61..812e4447a223 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1347,6 +1347,16 @@ static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash, __be3
         return oldest;
 }
 
+static inline u32 fnhe_hashfun(__be32 daddr)
+{
+        u32 hval;
+
+        hval = (__force u32) daddr;
+        hval ^= (hval >> 11) ^ (hval >> 22);
+
+        return hval & (FNHE_HASH_SIZE - 1);
+}
+
 static struct fib_nh_exception *find_or_create_fnhe(struct fib_nh *nh, __be32 daddr)
 {
         struct fnhe_hash_bucket *hash = nh->nh_exceptions;
@@ -1361,8 +1371,7 @@ static struct fib_nh_exception *find_or_create_fnhe(struct fib_nh *nh, __be32 da
                         return NULL;
         }
 
-        hval = (__force u32) daddr;
-        hval ^= (hval >> 11) ^ (hval >> 22);
+        hval = fnhe_hashfun(daddr);
         hash += hval;
 
         depth = 0;
@@ -1890,8 +1899,7 @@ static void rt_bind_exception(struct rtable *rt, struct fib_nh *nh, __be32 daddr
         struct fib_nh_exception *fnhe;
         u32 hval;
 
-        hval = (__force u32) daddr;
-        hval ^= (hval >> 11) ^ (hval >> 22);
+        hval = fnhe_hashfun(daddr);
 
         for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
              fnhe = rcu_dereference(fnhe->fnhe_next)) {