From patchwork Thu Oct 17 19:39:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 11197025 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1E50B14DB for ; Thu, 17 Oct 2019 19:39:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0671721A4C for ; Thu, 17 Oct 2019 19:39:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439958AbfJQTjq (ORCPT ); Thu, 17 Oct 2019 15:39:46 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:45066 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2437753AbfJQTjq (ORCPT ); Thu, 17 Oct 2019 15:39:46 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1iLBce-0006fW-06; Thu, 17 Oct 2019 19:39:44 +0000 From: Al Viro To: linux-scsi@vger.kernel.org Cc: Linus Torvalds , linux-kernel@vger.kernel.org, Al Viro Subject: [RFC PATCH 6/8] sg_read(): get rid of access_ok()/__copy_..._user() Date: Thu, 17 Oct 2019 20:39:23 +0100 Message-Id: <20191017193925.25539-6-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191017193925.25539-1-viro@ZenIV.linux.org.uk> References: <20191017193659.GA18702@ZenIV.linux.org.uk> <20191017193925.25539-1-viro@ZenIV.linux.org.uk> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Al Viro Use copy_..._user() instead, both in sg_read() and in sg_read_oxfer(). And don't open-code memdup_user()... Signed-off-by: Al Viro --- drivers/scsi/sg.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 3702f66493f7..9f6534a025cd 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -429,16 +429,10 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_read: count=%d\n", (int) count)); - if (!access_ok(buf, count)) - return -EFAULT; if (sfp->force_packid && (count >= SZ_SG_HEADER)) { - old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); - if (!old_hdr) - return -ENOMEM; - if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) { - retval = -EFAULT; - goto free_old_hdr; - } + old_hdr = memdup_user(buf, SZ_SG_HEADER); + if (IS_ERR(old_hdr)) + return PTR_ERR(old_hdr); if (old_hdr->reply_len < 0) { if (count >= SZ_SG_IO_HDR) { sg_io_hdr_t __user *p = (void __user *)buf; @@ -529,7 +523,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) /* Now copy the result back to the user buffer. */ if (count >= SZ_SG_HEADER) { - if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { + if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { retval = -EFAULT; goto free_old_hdr; } @@ -1960,12 +1954,12 @@ sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) num = 1 << (PAGE_SHIFT + schp->page_order); for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { if (num > num_read_xfer) { - if (__copy_to_user(outp, page_address(schp->pages[k]), + if (copy_to_user(outp, page_address(schp->pages[k]), num_read_xfer)) return -EFAULT; break; } else { - if (__copy_to_user(outp, page_address(schp->pages[k]), + if (copy_to_user(outp, page_address(schp->pages[k]), num)) return -EFAULT; num_read_xfer -= num;