From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1769925-1522223095-3-15840090663145130960 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='de', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-api-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1522223095; b=w0nKv0/VlnqO1KJDepmk6M3DFTnufA0S76WpOe97BzQnru7 o9wKMcI4kch15rRsIJ8rrm4jFaCLJbsvn8NjlUjVrICUl0hVaHHxF/tezYbK08bZ SU1xKwgEyByjqN2+tvdfbC6zYeDG6JXyRBNQmAvX62wpU8eVu9HhaCYWHovvMERK 3hKDkwPss9itavogntI57/s+0bKFccEKvVv87HIWlY3AZNT5RJMTWA+CzPc4JkSI Ik9e/jhGpi9D9bTnXFSRyLOt3yTMZM4AAjSXKWOl6TZce6jxHjSV8Naib89krciD h7yoXTLFUsmihELCipoXFns5GHt7GsgPZnLDrUA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:sender:list-id; s=arctest; t=1522223095; bh=OPqIGsTLcDtBV8m4sZv8Lre9QFV2pqnxhFhT1d9k/uY=; b=GkgEZ6BKPyXX qbBBa2G0on22BbUDgtItTgV85JSUVebEKJ1urvNEMRc4jNfwCDSLV9B8i9FV0u3g rZc9N8nZ/i1w/3hQKkWTm1yuT8m5le02MmLNJdDK7uieifVE8L/t2wyCUUcWa14f MrADtritTygPSOhrLQI2QpfTjdLgKLhqhIu6Q7inK2D54pc2Kd5d3PKQ4p/lZ4k0 U7B1VKPDGZlfNoJ4yc7mkP1dPDNM8Y/iGS0cKkp75Lu2queV3Yk3bEAh9c9bojZ6 5NOvRe4O1knT3uDHtPdQBKibkDW2KWZ6cyVhI7Jm9C7Q4ukd7zbXmoous95R/LhJ Rh7L5yf/Sg== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=kj66Xg3a x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=kj66Xg3a x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfCQnKuWA3dQfmcEmwsbS8Zviuik1nlnZLgoRfaui+8mQ8W3EayLej54Q5YdzSF0ZF03P2kVHhLFICnH0K/YTBVO0CUlbnHFOWOUoASbazIp9G5N4+bci LsG/ml5j8oQRjsmDNI143NzMiB+//eYQo6aLqXMjuQYn5YGO0sDmAmEcoxMSWUHHw72eHiiDsCyC71UvIejDchtxSUGYKkh3V/0bJWyMLpGj24AuW+UNM/CI X-CM-Analysis: v=2.3 cv=WaUilXpX c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=v2DPQv5-lfwA:10 a=20KFwNOVAAAA:8 a=ag1SF4gXAAAA:8 a=yPCof4ZbAAAA:8 a=VwQbUJbxAAAA:8 a=Zmq7VYwpCUWw3LpwOMAA:9 a=x8gzFH9gYPwA:10 a=Yupwre4RP9_Eg_Bd0iYG:22 a=AjGcO6oz07-iQ99wixmX:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752659AbeC1H1D (ORCPT ); Wed, 28 Mar 2018 03:27:03 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:44470 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752561AbeC1H1B (ORCPT ); Wed, 28 Mar 2018 03:27:01 -0400 From: Christoph Hellwig To: viro@zeniv.linux.org.uk Cc: Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/6] aio: sanitize ki_list handling Date: Wed, 28 Mar 2018 09:26:37 +0200 Message-Id: <20180328072639.16885-5-hch@lst.de> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180328072639.16885-1-hch@lst.de> References: <20180328072639.16885-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-api-owner@vger.kernel.org X-Mailing-List: linux-api@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Instead of handcoded non-null checks always initialize ki_list to an empty list and use list_empty / list_empty_careful on it. While we're at it also error out on a double call to kiocb_set_cancel_fn instead of ignoring it. Signed-off-by: Christoph Hellwig Acked-by: Jeff Moyer Reviewed-by: Greg Kroah-Hartman Reviewed-by: Darrick J. Wong --- fs/aio.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 50c4a0554cc6..f35801d73e0b 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -555,13 +555,12 @@ void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) struct kioctx *ctx = req->ki_ctx; unsigned long flags; - spin_lock_irqsave(&ctx->ctx_lock, flags); - - if (!req->ki_list.next) - list_add(&req->ki_list, &ctx->active_reqs); + if (WARN_ON_ONCE(!list_empty(&req->ki_list))) + return; + spin_lock_irqsave(&ctx->ctx_lock, flags); + list_add_tail(&req->ki_list, &ctx->active_reqs); req->ki_cancel = cancel; - spin_unlock_irqrestore(&ctx->ctx_lock, flags); } EXPORT_SYMBOL(kiocb_set_cancel_fn); @@ -1034,7 +1033,7 @@ static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx) goto out_put; percpu_ref_get(&ctx->reqs); - + INIT_LIST_HEAD(&req->ki_list); req->ki_ctx = ctx; return req; out_put: @@ -1080,7 +1079,7 @@ static void aio_complete(struct aio_kiocb *iocb, long res, long res2) unsigned tail, pos, head; unsigned long flags; - if (iocb->ki_list.next) { + if (!list_empty_careful(&iocb->ki_list)) { unsigned long flags; spin_lock_irqsave(&ctx->ctx_lock, flags); -- 2.14.2