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 AFB5BC43217 for ; Wed, 23 Nov 2022 09:09:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237073AbiKWJJO (ORCPT ); Wed, 23 Nov 2022 04:09:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237124AbiKWJI7 (ORCPT ); Wed, 23 Nov 2022 04:08:59 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC132240B1 for ; Wed, 23 Nov 2022 01:08:57 -0800 (PST) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 88F7261B10 for ; Wed, 23 Nov 2022 09:08:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84434C433C1; Wed, 23 Nov 2022 09:08:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194537; bh=6QqdkLRmgk+TgWmk16E7hamPY8XXEoMQdN8mYGlQn7c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G0x6L+RLGyvOGRWAk+xUXEtFBjRM6IB4tJ1bY6Dg5IacS/pTxgl54a665OXAxcBLk QnikCViObB6b1spK03KgXpdHi0VIMWlOPZ0+jpdOUg7ktP9aJj/LwIrjmQc/Ozwq3/ x5kYhu0dKh/eHKFYtZV3THniNXw7mUwyk3QNwjfk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniil Tatianin , "Steven Rostedt (Google)" Subject: [PATCH 4.19 078/114] ring_buffer: Do not deactivate non-existant pages Date: Wed, 23 Nov 2022 09:51:05 +0100 Message-Id: <20221123084554.984744927@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084551.864610302@linuxfoundation.org> References: <20221123084551.864610302@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: Daniil Tatianin commit 56f4ca0a79a9f1af98f26c54b9b89ba1f9bcc6bd upstream. rb_head_page_deactivate() expects cpu_buffer to contain a valid list of ->pages, so verify that the list is actually present before calling it. Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. Link: https://lkml.kernel.org/r/20221114143129.3534443-1-d-tatianin@yandex-team.ru Cc: stable@vger.kernel.org Fixes: 77ae365eca895 ("ring-buffer: make lockless") Signed-off-by: Daniil Tatianin Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/ring_buffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1328,9 +1328,9 @@ static void rb_free_cpu_buffer(struct ri free_buffer_page(cpu_buffer->reader_page); - rb_head_page_deactivate(cpu_buffer); - if (head) { + rb_head_page_deactivate(cpu_buffer); + list_for_each_entry_safe(bpage, tmp, head, list) { list_del_init(&bpage->list); free_buffer_page(bpage);