From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4CA84242D6E; Tue, 29 Apr 2025 17:14:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745946887; cv=none; b=OkXzBz+UFbzGJY70wFSUWyz0+MHRQXPFwp0Zrqq8rUX97YgmM4vBw1iXeXtbLTyer/Ud5vPYk0lXpyK3aQj2usBSXv9DzVnZdFEldvHah+/YiDSVWzi8BkYmuf8FGfAyYqPMLlOWjyekSt5WQON9hbXj610gWYOY9pQQEMzIiIs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745946887; c=relaxed/simple; bh=llKZ9zZU5x/nw2Spwk1adBYhMG5hSsagjSkpa7G83+E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iwI7HUgspbHRut83kAyXVIqP3lghHm0fZCvefeF/OMzFbS1tq5HDjf46CuxnEJw9BCgUqIZPtnGfqNtxqIr1j8L/BpGILkKN9l5d29gSNvPLDYuH2nYGLTXF8phrXg4jf22mZ0cLmyigVZeu8LRVY27mgJe1oB173lEm1budNzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bNP6Drkl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bNP6Drkl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA6B0C4CEE3; Tue, 29 Apr 2025 17:14:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745946887; bh=llKZ9zZU5x/nw2Spwk1adBYhMG5hSsagjSkpa7G83+E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bNP6Drklkcy6qNjC30WVADiR2heb2lShsgp290g9BFDKoZmQ+q/UjFnI6C8Z6T0du N/TuQvmrsXZJL6EFfdTMZYQiawrWC7lyCHmhIK7zwYJbmOUDZwpskUfqZlc7uZbz0h LNYD2bt21xN6anW4aIuxnYYzMCKuC5GqKK0ifN4M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ilia Gavrilov , Johannes Berg Subject: [PATCH 5.10 071/286] wifi: mac80211: fix integer overflow in hwmp_route_info_get() Date: Tue, 29 Apr 2025 18:39:35 +0200 Message-ID: <20250429161110.776422538@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161107.848008295@linuxfoundation.org> References: <20250429161107.848008295@linuxfoundation.org> User-Agent: quilt/0.68 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gavrilov Ilia commit d00c0c4105e5ab8a6a13ed23d701cceb285761fa upstream. Since the new_metric and last_hop_metric variables can reach the MAX_METRIC(0xffffffff) value, an integer overflow may occur when multiplying them by 10/9. It can lead to incorrect behavior. Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE. Fixes: a8d418d9ac25 ("mac80211: mesh: only switch path when new metric is at least 10% better") Cc: stable@vger.kernel.org Signed-off-by: Ilia Gavrilov Link: https://patch.msgid.link/20250212082124.4078236-1-Ilia.Gavrilov@infotecs.ru Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/mac80211/mesh_hwmp.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/net/mac80211/mesh_hwmp.c +++ b/net/mac80211/mesh_hwmp.c @@ -360,6 +360,12 @@ u32 airtime_link_metric_get(struct ieee8 return (u32)result; } +/* Check that the first metric is at least 10% better than the second one */ +static bool is_metric_better(u32 x, u32 y) +{ + return (x < y) && (x < (y - x / 10)); +} + /** * hwmp_route_info_get - Update routing info to originator and transmitter * @@ -450,8 +456,8 @@ static u32 hwmp_route_info_get(struct ie (mpath->sn == orig_sn && (rcu_access_pointer(mpath->next_hop) != sta ? - mult_frac(new_metric, 10, 9) : - new_metric) >= mpath->metric)) { + !is_metric_better(new_metric, mpath->metric) : + new_metric >= mpath->metric))) { process = false; fresh_info = false; } @@ -521,8 +527,8 @@ static u32 hwmp_route_info_get(struct ie if ((mpath->flags & MESH_PATH_FIXED) || ((mpath->flags & MESH_PATH_ACTIVE) && ((rcu_access_pointer(mpath->next_hop) != sta ? - mult_frac(last_hop_metric, 10, 9) : - last_hop_metric) > mpath->metric))) + !is_metric_better(last_hop_metric, mpath->metric) : + last_hop_metric > mpath->metric)))) fresh_info = false; } else { mpath = mesh_path_add(sdata, ta);