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 548461A76A4; Tue, 30 Jul 2024 17:16:36 +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=1722359796; cv=none; b=nQsSRIbUV5XgMp07NNaqF5w6Rq2EXjNBLywV8jPNv0ZU2mSmblZL724kc+gjfG+ppMl1ktVIA0RZEdLDVRGfAKIfJpE6Zlhaw/Hg4ZTSE7x7DFTCyUv/szwr3d908gtaHWxSG/TxVZ9mYB+vtz79ZYWkWncVVJ/C0bygyQ4LMTo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722359796; c=relaxed/simple; bh=ZOQZFea79a5kJlyxP2BMUZ7RdqZVwcUgdkKnqIRjeSs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Jk8xWDejRMKr67e3sxS5bkGsBADUUUp/6alj8RTX6cYasrqOnl1IbksDLCzhBQXd9leEDZlcNA7ncnzJ1lcANBGj+WqD+Ksb/E4A212t1HOWDrTdxGAvb++mMRA3eFfudhAt6xRY9cddeQPD7fNOrmv2041IVcmcK85jvU8KRzI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XRshA8lB; 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="XRshA8lB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7197C32782; Tue, 30 Jul 2024 17:16:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1722359796; bh=ZOQZFea79a5kJlyxP2BMUZ7RdqZVwcUgdkKnqIRjeSs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XRshA8lB7gTo1QF4YTqccBny5FlwwIyn8WDU/jyrYpSkXhGdKnE7b/gQbfPFAzyde 3laAvzKohw5Y5BKHAgXeFpBD0fJQijc4iwZU6B3CMstrtQLoddztpii7oCRLWPMuQc aBEycveG+K1PnGTG4xUA8IOz07zX7a6cHEqKxz4k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiri Pirko , Johannes Berg , Jay Vosburgh , Paolo Abeni , Sasha Levin Subject: [PATCH 6.6 537/568] net: bonding: correctly annotate RCU in bond_should_notify_peers() Date: Tue, 30 Jul 2024 17:50:44 +0200 Message-ID: <20240730151701.142253257@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240730151639.792277039@linuxfoundation.org> References: <20240730151639.792277039@linuxfoundation.org> User-Agent: quilt/0.67 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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg [ Upstream commit 3ba359c0cd6eb5ea772125a7aededb4a2d516684 ] RCU use in bond_should_notify_peers() looks wrong, since it does rcu_dereference(), leaves the critical section, and uses the pointer after that. Luckily, it's called either inside a nested RCU critical section or with the RTNL held. Annotate it with rcu_dereference_rtnl() instead, and remove the inner RCU critical section. Fixes: 4cb4f97b7e36 ("bonding: rebuild the lock use for bond_mii_monitor()") Reviewed-by: Jiri Pirko Signed-off-by: Johannes Berg Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20240719094119.35c62455087d.I68eb9c0f02545b364b79a59f2110f2cf5682a8e2@changeid Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/bonding/bond_main.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 34880b2db8050..722ac5c4992c9 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1121,13 +1121,10 @@ static struct slave *bond_find_best_slave(struct bonding *bond) return bestslave; } +/* must be called in RCU critical section or with RTNL held */ static bool bond_should_notify_peers(struct bonding *bond) { - struct slave *slave; - - rcu_read_lock(); - slave = rcu_dereference(bond->curr_active_slave); - rcu_read_unlock(); + struct slave *slave = rcu_dereference_rtnl(bond->curr_active_slave); if (!slave || !bond->send_peer_notif || bond->send_peer_notif % -- 2.43.0