6.12-stable review patch. If anyone has any objections, please let me know.
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From: Ido Schimmel idosch@nvidia.com
[ Upstream commit b6b638bda240395dff49a87403b2e32493e56d2a ]
mlxsw_sp_router_schedule_work() takes a reference on a neighbour, expecting a work item to release it later on. However, we might fail to schedule the work item, in which case the neighbour reference count will be leaked.
Fix by taking the reference just before scheduling the work item. Note that mlxsw_sp_router_schedule_work() can receive a NULL neighbour pointer, but neigh_clone() handles that correctly.
Spotted during code review, did not actually observe the reference count leak.
Fixes: 151b89f6025a ("mlxsw: spectrum_router: Reuse work neighbor initialization in work scheduler") Reviewed-by: Petr Machata petrm@nvidia.com Signed-off-by: Ido Schimmel idosch@nvidia.com Signed-off-by: Petr Machata petrm@nvidia.com Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/ec2934ae4aca187a8d8c9329a08ce93cca411378.1764695650... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 511cd92e0e3e7..4ab58cb1ab7f4 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -2858,6 +2858,11 @@ static int mlxsw_sp_router_schedule_work(struct net *net, if (!net_work) return NOTIFY_BAD;
+ /* Take a reference to ensure the neighbour won't be destructed until + * we drop the reference in the work item. + */ + neigh_clone(n); + INIT_WORK(&net_work->work, cb); net_work->mlxsw_sp = router->mlxsw_sp; net_work->n = n; @@ -2881,11 +2886,6 @@ static int mlxsw_sp_router_schedule_neigh_work(struct mlxsw_sp_router *router, struct net *net;
net = neigh_parms_net(n->parms); - - /* Take a reference to ensure the neighbour won't be destructed until we - * drop the reference in delayed work. - */ - neigh_clone(n); return mlxsw_sp_router_schedule_work(net, router, n, mlxsw_sp_router_neigh_event_work); }