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 9419C44AB8E; Tue, 21 Jul 2026 22:21:05 +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=1784672466; cv=none; b=PN1dgdmrJ8SAGlplrPbS5dAo2ChRpIuW4icF6SQzNTeaK4eAUfIuQg3781KH4gBx1NiBGMH4PF0J0zK0QP7bFTzWyGK6twTyS9zce45C1EnENB6Y42t70mFUpYzVvDd1EFsq+1pSPPvikxgxKYAz6DaWvsdbR5RaKzlC2FMuJLQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784672466; c=relaxed/simple; bh=SBPXrNcvoIZkql19Dv8/kGPbKYcowi2Ra5IUEgIMgdI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UKj8KzK5yC9EDqPIjGJ2VcKWoinj7L//Qd8UZkTsAWBJm2I24/12QlcYzlgyjYhqgEEY199yaaJdavOJwYQVS74zeQnzekFnFzEuLvrSn+o3J2JcVz89hihdljWzGC+TMi3g/HFJdQlTqo2NERkgw82W95kdYrxHY+PlvBTiPqo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0k6ahAQJ; 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="0k6ahAQJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0042A1F000E9; Tue, 21 Jul 2026 22:21:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784672465; bh=0B3W2pqyC+VsoI278AsIetTh+rH64gYXy0pzbGl8i7o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=0k6ahAQJcYwc4pEVeXHSZCzIUSHnPKS6yymtR215rLBypJhpuOLUiA/FUAkLn0Hcj 6UO0YzoL/zwHd0TWKV0Jm/3y+jiMafOLMorbAYz/ggaPRQQC50ZS6z+o/L48qE2Z0o MMhxabLClzLlmqtVRKcFvoscieZfZkCg7yHQAgxQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Eckelmann Subject: [PATCH 5.15 592/843] batman-adv: dat: fix tie-break for candidate selection Date: Tue, 21 Jul 2026 17:23:47 +0200 Message-ID: <20260721152419.368614488@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152405.946368001@linuxfoundation.org> References: <20260721152405.946368001@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit 98052bdaf6ac1639a63ffc10244eeeab1f62ed2b upstream. The original version of the candidate selection for DAT attempted to compare both candidate and max_orig_node to identify which has the smaller MAC address. This comparison is required as tie-break when a hash collision happened. But the used function returned 0 when the function was not equal and a non-zero value when it was equal. As result, the actually selected node was dependent on the order of entries in the orig_hash and not actually on the mac addresses. The last originator in the hash collision would always win. To have a proper ordering, it must diff the actual MAC address bytes and reject the candidate when the diff is not smaller than 0. Cc: stable@vger.kernel.org Fixes: 785ea1144182 ("batman-adv: Distributed ARP Table - create DHT helper functions") Signed-off-by: Sven Eckelmann Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/distributed-arp-table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -546,7 +546,7 @@ static bool batadv_is_orig_node_eligible * the one with the lowest address */ if (tmp_max == max && max_orig_node && - batadv_compare_eth(candidate->orig, max_orig_node->orig)) + memcmp(candidate->orig, max_orig_node->orig, ETH_ALEN) >= 0) goto out; ret = true;