rtnl_net_cmp_locks() always returns -1 if CONFIG_DEBUG_NET_SMALL_RTNL is disabled. However, if CONFIG_DEBUG_NET_SMALL_RTNL is enabled, it returns 0 when both inputs are equal. It is then used by rtnl_nets_add() to call put_net() if the net to be added is already present in the struct rtnl_nets. As a result, when rtnl_nets_add() is called on an already present net, put_net() is called only if DEBUG is on.
Add the input comparison in the DEBUG off case so that put_net() is always called in this scenario.
Fixes: cbaaa6326bc5 ("rtnetlink: Introduce struct rtnl_nets and helpers.") Cc: stable@vger.kernel.org Signed-off-by: Bastien Curutchet (eBPF Foundation) bastien.curutchet@bootlin.com --- net/core/rtnetlink.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index cb7fad8d1f95ff287810229c341de6a6d20a9c07..94111d3383788566f2296039e68549e2b40d5a4a 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -275,6 +275,9 @@ EXPORT_SYMBOL(lockdep_rtnl_net_is_held); #else static int rtnl_net_cmp_locks(const struct net *net_a, const struct net *net_b) { + if (net_eq(net_a, net_b)) + return 0; + /* No need to swap */ return -1; }