From patchwork Tue Nov 13 05:51:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sasha Levin X-Patchwork-Id: 10679691 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A057013BB for ; Tue, 13 Nov 2018 05:58:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 90DD029FAC for ; Tue, 13 Nov 2018 05:58:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 84DF02A264; Tue, 13 Nov 2018 05:58:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 294DE2A278 for ; Tue, 13 Nov 2018 05:58:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732477AbeKMPsT (ORCPT ); Tue, 13 Nov 2018 10:48:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:34586 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732459AbeKMPsT (ORCPT ); Tue, 13 Nov 2018 10:48:19 -0500 Received: from sasha-vm.mshome.net (unknown [64.114.255.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9F3492250E; Tue, 13 Nov 2018 05:51:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542088311; bh=op6nsWTVZkB6XPznwUJV6PUajPDInOi/9GQa/giGMBA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a7czCC6oJwOywuBmC/LFNErOrqwtPI4QRamPQm9PbENrgm027NIPW1Yz/YgxmizZB 8KH7Chk7iczPPPGsJGoWZ2D2a9LMzYRYatiSybzqtO3Jyn5Ekx3xN8wuAfpyAIoMcY e2TfZ7KTfs6EY8oNV0ZW8iUSMUOpPHQCgWRLIWQo= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Ronnie Sahlberg , Steve French , Sasha Levin , linux-cifs@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 03/26] cifs: fix return value for cifs_listxattr Date: Tue, 13 Nov 2018 00:51:27 -0500 Message-Id: <20181113055150.78773-3-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181113055150.78773-1-sashal@kernel.org> References: <20181113055150.78773-1-sashal@kernel.org> Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Ronnie Sahlberg [ Upstream commit 0c5d6cb6643f48ad3775322f3ebab6c7eb67484e ] If the application buffer was too small to fit all the names we would still count the number of bytes and return this for listxattr. This would then trigger a BUG in usercopy.c Fix the computation of the size so that we return -ERANGE correctly when the buffer is too small. This fixes the kernel BUG for xfstest generic/377 Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Reviewed-by: Aurelien Aptel Signed-off-by: Sasha Levin --- fs/cifs/smb2ops.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 4e5b05263e4a..3372eedaa94d 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -441,6 +441,7 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size, int rc = 0; unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0; char *name, *value; + size_t buf_size = dst_size; size_t name_len, value_len, user_name_len; while (src_size > 0) { @@ -476,9 +477,10 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size, /* 'user.' plus a terminating null */ user_name_len = 5 + 1 + name_len; - rc += user_name_len; - - if (dst_size >= user_name_len) { + if (buf_size == 0) { + /* skip copy - calc size only */ + rc += user_name_len; + } else if (dst_size >= user_name_len) { dst_size -= user_name_len; memcpy(dst, "user.", 5); dst += 5; @@ -486,8 +488,7 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size, dst += name_len; *dst = 0; ++dst; - } else if (dst_size == 0) { - /* skip copy - calc size only */ + rc += user_name_len; } else { /* stop before overrun buffer */ rc = -ERANGE;