From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2684081-1520286177-2-8578182530264785157 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 enrosv, 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=1520286177; b=IjTHeyeOqk4Wjd3vsy76h5NQJj6ktRlfeEOzdG8aIive+eF QkW8tZ4LMjZdhjPweYDZRqSrLhiZAOgZI/jy9/FiKldddlDD+SRWwAZU35AeZusM SEbR1wmYgyd81yfedu6fYqlDnpd/2z9muW/RTpl3Q/dvAuwJLrLDTsFDghouRI1y Fb2vGSXlDZ95+FSKZNn0zlzsrUGXZWbKcfebHojkmChYTHVAEUZ7Dy7s8/++Wt6A UxzqZTMvUTfomcwe0yjFsjYWqrJuWsEhQQZcIj9O42CLBozegHZfdX9EHAHPJbna Rj7LOOAyk0+sk0V9gstGiDt1j2Zhv6ulehVm95Q== 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=1520286177; bh=d0m+AKIKiFglhLqjWHeYqQ2HEgwi+KebFzgyQf51WD0=; b=PSijtWxn+U9j FkYfh69rAK4Db3wT0SgoR8Lrm3rk52f8OypoeIXAlFdn+WKo4DivjEJTIhT/NdRP t4Ue3tbJE0B+LUJgAX9bK6QixOBM13sAaVtfP33lpqEL0aoywbQBBKXaVwkxVqG7 w1v6EyqLDcabVWL9PciXfHFVE67+N4zTRd5CT3ruR1ohw5Blb73aySCbvAjli1fp tziCf/VxaMy9mOjSoZcBiGGDKwdbkrHUS7fYtaAxp8mZpN/ctV3VG8a8d0Yp3Eha Xxa2lVTDdYEei7qKdW1QZSX7tV8qbmQymGhvLw0kzc3f7GRiMbfizZ56ipDRs0KA I7KI5H1yGw== ARC-Authentication-Results: i=1; mx5.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=fyNSlUfh 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-category=clean score=0 state=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 Authentication-Results: mx5.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=fyNSlUfh 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-category=clean score=0 state=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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933141AbeCEVkC (ORCPT ); Mon, 5 Mar 2018 16:40:02 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:60630 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932406AbeCEV1u (ORCPT ); Mon, 5 Mar 2018 16:27:50 -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, 5 Mar 2018 13:27:11 -0800 Message-Id: <20180305212743.16664-5-hch@lst.de> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180305212743.16664-1-hch@lst.de> References: <20180305212743.16664-1-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