From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D282318B9D; Thu, 2 Jul 2026 16:53:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783011195; cv=none; b=n2FRFUx/TSjHqCIlGdtE4oY9f8Y3qnaV+NpjZ73vHGgoeEo/uSZOnBPJQBmYLh8zm3qq2Rudf5VXjgmZdsWf+WLEB9stwuQBHJFYMiXsM6gMWYwyaC+IW6Ix/V4c4PTUIu1OdsE8g6cfL4Guj0EEAsO5n9odnFCFpoLbHnqHI40= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783011195; c=relaxed/simple; bh=h0pY7yrrJHxe2sLoF7xDiHhpRWFFgoPuBDqRsfI6Rwg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HhjB6IUyhrU90ujeVqokdwVX2dGqs4jACVU04ya1EweU+jsQFSykLjG96l1mcmo+0RCLy346Ov5LzCfX7I0KVYkHdhhY776FDgErQRnWP0Jns6igEATXifJXYXvf/3Zu+kl9mJ+ZjRYDX3UKTEkd/BmgLplapSrWOHwkkmiIIOQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RJknhfjw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="RJknhfjw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2C591F000E9; Thu, 2 Jul 2026 16:53:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1783011194; bh=CvscdMwCTgF363hdLIv22rsUpG3/XaV/b7m0C3wWUfE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RJknhfjw+OOdbWAYLFpKLwscD3fL9yrkNzJVFKzxWi5M/VqtmUH6X8KydjTOpd07G SV3cZltIzsvlvG2q8WPKkQFYdj5dmQXhwALAdqIteld1Y8+nFV8pvZ6LWFx9PtksBk A+gylziV8ECBk6YHZyXoi/x//49kuh3SdqDpaRag= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Nora Schiffer , Sven Eckelmann , Sasha Levin Subject: [PATCH 6.18 017/108] batman-adv: gw: dont deselect gateway with active hardif Date: Thu, 2 Jul 2026 18:20:14 +0200 Message-ID: <20260702155112.466830154@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260702155112.110058792@linuxfoundation.org> References: <20260702155112.110058792@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit df97a7107b16375a10a36d7a63e9b4291a8ac680 upstream. The batadv_hardif_cnt() was previously checking if there is an batadv_hard_iface->mesh_iface which is has the same mesh_iface. And since batadv_hardif_disable_interface() was resetting the batadv_hard_iface->mesh_iface after this check, it had to verify whether *1* interface was still part of the mesh_iface before it started the gateway deselection. But after batadv_hardif_cnt() is now checking the lower interfaces of mesh_iface and batadv_hardif_disable_interface() already removed the interface via netdev_upper_dev_unlink() earlier in this function, the check must now make sure that *0* interfaces can be found by batadv_hardif_cnt() before selected gateway must be deselected. Otherwise the deselection would already happen one batadv_hard_iface too early. Because a 0 hardif count from batadv_hardif_cnt() is equal to an empty list, it is possible to replace the counting with a simple list_empty(). Cc: stable@kernel.org Fixes: 7dc284702bcd ("batman-adv: store hard_iface as iflink private data") Reviewed-by: Nora Schiffer Signed-off-by: Sven Eckelmann Signed-off-by: Sasha Levin --- net/batman-adv/hard-interface.c | 28 ++-------------------------- 1 file changed, 2 insertions(+), 26 deletions(-) diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 1c488049d55463..39b1ed813497d2 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -786,30 +786,6 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, return ret; } -/** - * batadv_hardif_cnt() - get number of interfaces enslaved to mesh interface - * @mesh_iface: mesh interface to check - * - * This function is only using RCU for locking - the result can therefore be - * off when another function is modifying the list at the same time. The - * caller can use the rtnl_lock to make sure that the count is accurate. - * - * Return: number of connected/enslaved hard interfaces - */ -static size_t batadv_hardif_cnt(struct net_device *mesh_iface) -{ - struct batadv_hard_iface *hard_iface; - struct list_head *iter; - size_t count = 0; - - rcu_read_lock(); - netdev_for_each_lower_private_rcu(mesh_iface, hard_iface, iter) - count++; - rcu_read_unlock(); - - return count; -} - /** * batadv_hardif_disable_interface() - Remove hard interface from mesh interface * @hard_iface: hard interface to be removed @@ -850,8 +826,8 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface) netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->mesh_iface); batadv_hardif_recalc_extra_skbroom(hard_iface->mesh_iface); - /* nobody uses this interface anymore */ - if (batadv_hardif_cnt(hard_iface->mesh_iface) <= 1) + /* nobody uses this mesh interface anymore */ + if (list_empty(&hard_iface->mesh_iface->adj_list.lower)) batadv_gw_check_client_stop(bat_priv); hard_iface->mesh_iface = NULL; -- 2.53.0