Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Maor Gottlieb <maorg@nvidia.com>,
        Mark Bloch <mbloch@nvidia.com>,
        Saeed Mahameed <saeedm@nvidia.com>
Subject: [PATCH 5.16 091/164] net/mlx5: Fix possible deadlock on rule deletion
Date:   Mon, 28 Feb 2022 18:24:13 +0100
Message-Id: <20220228172408.084994170@linuxfoundation.org>
In-Reply-To: <20220228172359.567256961@linuxfoundation.org>
References: <20220228172359.567256961@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Maor Gottlieb <maorg@nvidia.com>

commit b645e57debca846f51b3209907546ea857ddd3f5 upstream.

Add missing call to up_write_ref_node() which releases the semaphore
in case the FTE doesn't have destinations, such in drop rule case.

Fixes: 465e7baab6d9 ("net/mlx5: Fix deletion of duplicate rules")
Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/fs_core.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c
@@ -2073,6 +2073,8 @@ void mlx5_del_flow_rules(struct mlx5_flo
 		fte->node.del_hw_func = NULL;
 		up_write_ref_node(&fte->node, false);
 		tree_put_node(&fte->node, false);
+	} else {
+		up_write_ref_node(&fte->node, false);
 	}
 	kfree(handle);
 }