FAILED: patch "[PATCH] mlxsw: fix refcount leak in mlxsw_sp_port_lag_join()" failed to apply to 5.10-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 41c8c1d65b32beacd8d916a22457b4f6e47f45af
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026072025-thirsting-chance-450b@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 41c8c1d65b32beacd8d916a22457b4f6e47f45af Mon Sep 17 00:00:00 2001
From: Wentao Liang <vulab@iscas.ac.cn>
Date: Tue, 9 Jun 2026 08:37:09 +0000
Subject: [PATCH] mlxsw: fix refcount leak in mlxsw_sp_port_lag_join()

When mlxsw_sp_port_lag_index_get() fails, mlxsw_sp_port_lag_join()
returns an error without releasing the lag reference obtained by
the earlier mlxsw_sp_lag_get().  All other error paths in the
function jump to the cleanup label that ends with
mlxsw_sp_lag_put(), so this is a single missed release.

Fix the leak by replacing the bare 'return err' with a goto to the
existing error cleanup label, which will drop the reference safely.

Cc: stable@vger.kernel.org
Fixes: 0d65fc13042f ("mlxsw: spectrum: Implement LAG port join/leave")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260609083709.209743-1-vulab@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 1aaa75b47fe3..82569162d2e5 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -4360,7 +4360,7 @@ static int mlxsw_sp_port_lag_join(struct mlxsw_sp_port *mlxsw_sp_port,
 	lag_id = lag->lag_id;
 	err = mlxsw_sp_port_lag_index_get(mlxsw_sp, lag_id, &port_index);
 	if (err)
-		return err;
+		goto err_lag_uppers_bridge_join;
 
 	err = mlxsw_sp_lag_uppers_bridge_join(mlxsw_sp_port, lag_dev,
 					      extack);