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 69F1647141A; Tue, 21 Jul 2026 19:53:25 +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=1784663606; cv=none; b=jRhIZA0//DtUHlVnIfrDJOqQI+nvFW3Vdi5pSN+6pTbAjxO28JOH6S7kZ6mWn2bOcHY14QPzJYzU9tCIuliU4iyE4vbcjTvCRsT6St+pK5XRnvxCFtBzqU8yerC5I78v0dJJGwZ/W7cWANvyAVDUkxkic9k166VM0+pxGTHwAlc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784663606; c=relaxed/simple; bh=928X3bFs63iWPYBMWHfiYdBbtYRbWzfxyjHRl2G1Sjc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JKQVnxAT8UQyngNRpAF478GTpaEYLisNA0QZhNQDbOrcromrld1y6LFMOpg8MpF8agDFolGVrEypS/2Y/MTG1PJVTfW9KZYG5dvS63KO46H9qa4j1Rz8uAcT4ntq9UXqg/TkB3v630dGWCLvi7+YBESXFdjX7XjxomrENXxPp9E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=i59uLoU9; 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="i59uLoU9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C12001F000E9; Tue, 21 Jul 2026 19:53:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784663605; bh=WGM+BtD9iRdiRp3YKFr+HKuvVM3tpVXpP+2zLo5G5uM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=i59uLoU9cVkxQ6yGlKQcXsyVQN4bjHcnLz6lzM26dk5hHp2TxiUWNgZUm8tddbDS7 T0oWWis7iS/ABZDIMEg9kHwKO9VqJID8L4YQff5c/K/9uT3H+xnhvziMR1pySiXERV fGvApL/eg3AVUgxWFYkedHBB/Oi6p+CKMGa+S2Is= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sven Eckelmann Subject: [PATCH 6.12 0887/1276] batman-adv: dat: fix tie-break for candidate selection Date: Tue, 21 Jul 2026 17:22:10 +0200 Message-ID: <20260721152505.898149643@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152446.065700225@linuxfoundation.org> References: <20260721152446.065700225@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 6.12-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;