From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2380693-1516652955-2-17120673122403974471 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 0.25, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enrosv, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', 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=1516652954; b=jyOsdSCKUXjOq4Z47QZO3Y0z5CjKRac9Sxc/5VnxOn2Q8SK TmBdl4SPliBzqQsc1DogIta7iAnSClk5LysFfoJ5XAWwUFeC1uXLCHHvCy7I/HVS 9GSrhNbMTj0TZwpyX8fKaHHvUgK3eiVbNwlTTwnd54e2h2T9yTPWaxeifMZ3l694 QFYuBj9VSEfUcvSq5c8AASbp9s/TxrQeSnlByFYBhL9kNBlTHbPdaKnbiihe9wTH kuop/Kp8iIpiFwBORczWQQXMZtTsR8DVv32assZqqJaRbIIdJDeGsCct/pgE+g5r hxkhxPz3gPe++SDpSgT/xlTipaokZHRYm3svMvA== 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=1516652954; bh=d0m+AKIKiFglhLqjWHeYqQ2HEgwi+KebFzgyQf51WD0=; b=Da8W9bHYNaGQ X3Lgsj7Vhdg3ydTWDyBCO4B8GnGXvsojmQ+3WtXXvN1yFiHZnuxdHYt3jqkfVFgd nTGqtHG7x0UE6n2qjsZ9BpPIzpdwuGcEz5E3P7hMQMmMmGFKmb0fAATkf0xFgboP JTEYO771NkM5HgmPuOaLm9410dJVzrPb3Hgx8p9FKewsCJeaRM+h8oRxRoEbOat1 OzEKonWxEZIh7no9YGrnWgrRrYKhez2xF1ndCecO6lj/w5EJs9ho7lzwi+0+B6/F FUJMTHZfV/Wnqnn1rGflrYUSFPfju3VUzamTS9m4SoAaRXT08T94GyNQyisuO6Bf 7tDd/Yab2A== ARC-Authentication-Results: i=1; mx3.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=cBaaOUAv 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-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 Authentication-Results: mx3.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=cBaaOUAv 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-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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751368AbeAVUNH (ORCPT ); Mon, 22 Jan 2018 15:13:07 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:54561 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750973AbeAVUNC (ORCPT ); Mon, 22 Jan 2018 15:13:02 -0500 From: Christoph Hellwig To: viro@zeniv.linux.org.uk Cc: Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 04/36] aio: sanitize ki_list handling Date: Mon, 22 Jan 2018 21:12:11 +0100 Message-Id: <20180122201243.31610-5-hch@lst.de> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180122201243.31610-1-hch@lst.de> References: <20180122201243.31610-1-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 --- fs/aio.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 6295fc00f104..c32c315f05b5 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.next)) { unsigned long flags; spin_lock_irqsave(&ctx->ctx_lock, flags); -- 2.14.2