From patchwork Tue May 23 12:48:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13252218 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 7321FC7EE29 for ; Tue, 23 May 2023 12:49:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234057AbjEWMtm (ORCPT ); Tue, 23 May 2023 08:49:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236635AbjEWMtl (ORCPT ); Tue, 23 May 2023 08:49:41 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81E5B129 for ; Tue, 23 May 2023 05:48:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684846127; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=hz+rQBDAcdUtSJzBU0XZBYw1XZqw4mtBlUpMTPXSzN4=; b=L6ulmRGBHE/ZM9gC/X6G2dOXIbIONi1c047yTiruBC5cpW8wgmRCANoYJbv7xSw7ocGoWs XRzRROLRccCuQea8vd4eAUPrfierkCw3GlgcBSb5fIsRBeC5mg56qk9KXnSMKIOAZwSm7e cVFJynatsBA3WbTMjN6CeCdIOFAeQEs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-36-2A2PiPSiNQaORPT8h7GuJQ-1; Tue, 23 May 2023 08:48:44 -0400 X-MC-Unique: 2A2PiPSiNQaORPT8h7GuJQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 35CF2811E93; Tue, 23 May 2023 12:48:43 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id C540A40CFD46; Tue, 23 May 2023 12:48:41 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells To: Shyam Prasad N cc: dhowells@redhat.com, Steve French , Rohith Surabattula , Paulo Alcantara , Tom Talpey , Jeff Layton , linux-cifs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] cifs: Fix cifs_limit_bvec_subset() to correctly check the maxmimum size MIME-Version: 1.0 Content-ID: <2989164.1684846121.1@warthog.procyon.org.uk> Date: Tue, 23 May 2023 13:48:41 +0100 Message-ID: <2989165.1684846121@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Fix cifs_limit_bvec_subset() so that it limits the span to the maximum specified and won't return with a size greater than max_size. Fixes: d08089f649a0 ("cifs: Change the I/O paths to use an iterator rather than a page list") Reported-by: Shyam Prasad N Signed-off-by: David Howells cc: Steve French cc: Rohith Surabattula cc: Paulo Alcantara cc: Tom Talpey cc: Jeff Layton cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org --- fs/cifs/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/cifs/file.c b/fs/cifs/file.c index ba7f2e09d6c8..df88b8c04d03 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -3353,9 +3353,10 @@ static size_t cifs_limit_bvec_subset(const struct iov_iter *iter, size_t max_siz while (n && ix < nbv) { len = min3(n, bvecs[ix].bv_len - skip, max_size); span += len; + max_size -= len; nsegs++; ix++; - if (span >= max_size || nsegs >= max_segs) + if (max_size == 0 || nsegs >= max_segs) break; skip = 0; n -= len;