From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E720AC38A2D for ; Mon, 24 Oct 2022 16:06:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233159AbiJXQGg (ORCPT ); Mon, 24 Oct 2022 12:06:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233794AbiJXQFA (ORCPT ); Mon, 24 Oct 2022 12:05:00 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8D8B22510; Mon, 24 Oct 2022 07:57:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 942A9B8162B; Mon, 24 Oct 2022 12:22:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA29EC433D6; Mon, 24 Oct 2022 12:22:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666614145; bh=dcsN3cYuMFF+AYHBJhPzQlBwMzkk1P7+S/W9/R6kMy0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xO6vO4kavbJyacTK9+bE3XtZ0PZT06ha5V2WGrhmFTVnoOlqoSkye7jMwaiB/WDBF 06f9xz9WoANGMH8KVSiNMTitN8OswJ0uSjnhioIZDVW2c/maL9Yihnes7mGNJFl7Bj GPrZlTmAV/LNYjXL61WAMrWk1kbVyQQV1hSazMf8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lee Jones , Daniel Borkmann , Yonghong Song , Sasha Levin Subject: [PATCH 5.10 119/390] bpf: Ensure correct locking around vulnerable function find_vpid() Date: Mon, 24 Oct 2022 13:28:36 +0200 Message-Id: <20221024113027.745111211@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024113022.510008560@linuxfoundation.org> References: <20221024113022.510008560@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Lee Jones [ Upstream commit 83c10cc362d91c0d8d25e60779ee52fdbbf3894d ] The documentation for find_vpid() clearly states: "Must be called with the tasklist_lock or rcu_read_lock() held." Presently we do neither for find_vpid() instance in bpf_task_fd_query(). Add proper rcu_read_lock/unlock() to fix the issue. Fixes: 41bdc4b40ed6f ("bpf: introduce bpf subcommand BPF_TASK_FD_QUERY") Signed-off-by: Lee Jones Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220912133855.1218900-1-lee@kernel.org Signed-off-by: Sasha Levin --- kernel/bpf/syscall.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 419dbc3d060e..aaad2dce2be6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3915,7 +3915,9 @@ static int bpf_task_fd_query(const union bpf_attr *attr, if (attr->task_fd_query.flags != 0) return -EINVAL; + rcu_read_lock(); task = get_pid_task(find_vpid(pid), PIDTYPE_PID); + rcu_read_unlock(); if (!task) return -ENOENT; -- 2.35.1