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 X-Spam-Level: X-Spam-Status: No, score=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9ECBEC43441 for ; Mon, 19 Nov 2018 16:34:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 656D220989 for ; Mon, 19 Nov 2018 16:34:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="n/fL+cUr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 656D220989 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731322AbeKTC6R (ORCPT ); Mon, 19 Nov 2018 21:58:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:57282 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729995AbeKTC6Q (ORCPT ); Mon, 19 Nov 2018 21:58:16 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C422E20870; Mon, 19 Nov 2018 16:34:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542645248; bh=Zk1LFjWQ8Jn77RrKQoGKvpaBUWLh5cgR7kn/oyJWdIU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n/fL+cUrlEmzO8n/vopL8J3LTgMZfGDLEKVBrjVmmacIgkdCrnIaAFN5CervKFL+f dkf11du4I+di1w4n+CsWVwcUP4lPc4eThe30nsWtRdwZJ1Opls6MZyWv8K9+AUi8tv 8SAJCLGRI7w4a2IX9q08W8rggkSQOaIqCNOg8FKA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kirill Tkhai , Miklos Szeredi Subject: [PATCH 4.19 065/205] fuse: Fix use-after-free in fuse_dev_do_write() Date: Mon, 19 Nov 2018 17:26:12 +0100 Message-Id: <20181119162628.695796987@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181119162616.586062722@linuxfoundation.org> References: <20181119162616.586062722@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kirill Tkhai commit d2d2d4fb1f54eff0f3faa9762d84f6446a4bc5d0 upstream. After we found req in request_find() and released the lock, everything may happen with the req in parallel: cpu0 cpu1 fuse_dev_do_write() fuse_dev_do_write() req = request_find(fpq, ...) ... spin_unlock(&fpq->lock) ... ... req = request_find(fpq, oh.unique) ... spin_unlock(&fpq->lock) queue_interrupt(&fc->iq, req); ... ... ... ... ... request_end(fc, req); fuse_put_request(fc, req); ... queue_interrupt(&fc->iq, req); Signed-off-by: Kirill Tkhai Signed-off-by: Miklos Szeredi Fixes: 46c34a348b0a ("fuse: no fc->lock for pqueue parts") Cc: # v4.2 Signed-off-by: Greg Kroah-Hartman --- fs/fuse/dev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1877,16 +1877,20 @@ static ssize_t fuse_dev_do_write(struct /* Is it an interrupt reply? */ if (req->intr_unique == oh.unique) { + __fuse_get_request(req); spin_unlock(&fpq->lock); err = -EINVAL; - if (nbytes != sizeof(struct fuse_out_header)) + if (nbytes != sizeof(struct fuse_out_header)) { + fuse_put_request(fc, req); goto err_finish; + } if (oh.error == -ENOSYS) fc->no_interrupt = 1; else if (oh.error == -EAGAIN) queue_interrupt(&fc->iq, req); + fuse_put_request(fc, req); fuse_copy_finish(cs); return nbytes;