From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dvalin.narfation.org (dvalin.narfation.org [213.160.73.56]) (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 D681B30AD10 for ; Fri, 29 May 2026 20:12:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.160.73.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780085535; cv=none; b=Cwk2c5CCpk5jAnpYXFg2eMeRPCszoZVzukJzeDzZb8LtQqpPe9o188WgDqQG+hJ5iC8NIQdG1sRGciQYa7uNPzZf/4/ahImqVwrNYFopPCHbsVJUa9lhzGIt3sEyCrCR72D7qZlK/nv5qZ96byA422nPZ+Zlqcm7RTht4u9omQE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780085535; c=relaxed/simple; bh=6uo9VOFNsWxAf1OWZdrSerxTB+3yA0zUzOhkaUKljn4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rTB+IiyHPSFBt8iCI9imkg6PRkaehJnW5QhrDtSpICdtaz4gxzRuhHlnqMq7GqZUFRrcO4dDM55WKWSFt+gxcDnQ0CkLMVr8YCaH12T2A1qzG+k+q3l2A2uA8x+2S5IsiFaRkOVttmHwekUgoKZbdoZlskmNpXReu25krdVeVGQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=narfation.org; spf=pass smtp.mailfrom=narfation.org; dkim=pass (1024-bit key) header.d=narfation.org header.i=@narfation.org header.b=NsfeokEm; arc=none smtp.client-ip=213.160.73.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=narfation.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=narfation.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=narfation.org header.i=@narfation.org header.b="NsfeokEm" Received: by dvalin.narfation.org (Postfix) id 4647D1FE5D; Fri, 29 May 2026 20:12:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=narfation.org; s=20121; t=1780085532; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=S5At6lqcm58jfZTIpaiVpZ4rjlIKXw/FiO/VdVtiS5U=; b=NsfeokEmkwI62U3b6yGpEwzqMY/K7+63n24QtNvrtnnEGGanXUCZLwRatfOxk0dYMBbC0a 8+NhpeRlYBUSB2uAfodZJ9GLFEIaT32UNVaZ7M3bYRS0HZ30qUdad3HKyITNCJeaBXxQ3A mv6R6Hs4tJFlBaBAh4XyJklHcsDb0fQ= From: Sven Eckelmann To: stable@vger.kernel.org Cc: Sven Eckelmann , stable@kernel.org Subject: [PATCH 5.10.y] batman-adv: tt: avoid empty VLAN responses Date: Fri, 29 May 2026 22:12:08 +0200 Message-ID: <20260529201209.479331-1-sven@narfation.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <2026052844-procurer-jimmy-dfaa@gregkh> References: <2026052844-procurer-jimmy-dfaa@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit commit fa1bd704940b5bcbc32c0b28db9167405c8ee5e0 upstream. The commit 16116dac2339 ("batman-adv: prevent TT request storms by not sending inconsistent TT TLVLs") added checks to the local (direct) TT response code. But the response can also be done indirectly by another node using the global TT state. To avoid such inconsistency states reported in the original fix, also avoid sending empty VLANs for replies from the global TT state. Cc: stable@kernel.org Fixes: 7ea7b4a14275 ("batman-adv: make the TT CRC logic VLAN specific") [ Context, drop flex array dependency ] Signed-off-by: Sven Eckelmann --- net/batman-adv/translation-table.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index e9cbf6d2b5fa6..7310392accb94 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -848,17 +848,19 @@ batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node, s32 *tt_len) { u16 num_vlan = 0; - u16 num_entries = 0; u16 tvlv_len = 0; unsigned int change_offset; struct batadv_tvlv_tt_vlan_data *tt_vlan; struct batadv_orig_node_vlan *vlan; + u16 total_entries = 0; u8 *tt_change_ptr; + int vlan_entries; spin_lock_bh(&orig_node->vlan_list_lock); hlist_for_each_entry(vlan, &orig_node->vlan_list, list) { + vlan_entries = atomic_read(&vlan->tt.num_entries); + total_entries += vlan_entries; num_vlan++; - num_entries += atomic_read(&vlan->tt.num_entries); } change_offset = sizeof(**tt_data); @@ -866,7 +868,7 @@ batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node, /* if tt_len is negative, allocate the space needed by the full table */ if (*tt_len < 0) - *tt_len = batadv_tt_len(num_entries); + *tt_len = batadv_tt_len(total_entries); if (change_offset > U16_MAX || *tt_len > U16_MAX - change_offset) { *tt_len = 0; @@ -887,14 +889,27 @@ batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node, (*tt_data)->num_vlan = htons(num_vlan); tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1); + num_vlan = 0; hlist_for_each_entry(vlan, &orig_node->vlan_list, list) { + vlan_entries = atomic_read(&vlan->tt.num_entries); + if (vlan_entries < 1) + continue; + tt_vlan->vid = htons(vlan->vid); tt_vlan->crc = htonl(vlan->tt.crc); tt_vlan->reserved = 0; tt_vlan++; + num_vlan++; } + /* recalculate in case number of VLANs reduced */ + change_offset = sizeof(**tt_data); + change_offset += num_vlan * sizeof(*tt_vlan); + tvlv_len = *tt_len + change_offset; + + (*tt_data)->num_vlan = htons(num_vlan); + tt_change_ptr = (u8 *)*tt_data + change_offset; *tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr; -- 2.47.3