Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753496Ab0HBMlb (ORCPT ); Mon, 2 Aug 2010 08:41:31 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:43108 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751452Ab0HBMl3 (ORCPT ); Mon, 2 Aug 2010 08:41:29 -0400 Date: Mon, 2 Aug 2010 21:41:25 +0900 From: Simon Horman To: Kulikov Vasiliy Cc: kernel-janitors@vger.kernel.org, Greg Kroah-Hartman , H Hartley Sweeten , Joe Eloff , Randy Dunlap , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/9 v2] staging: dt3155: check put_user() return value Message-ID: <20100802124125.GG5814@verge.net.au> References: <1280737873-5992-1-git-send-email-segooon@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1280737873-5992-1-git-send-email-segooon@gmail.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2473 Lines: 63 On Mon, Aug 02, 2010 at 12:31:12PM +0400, Kulikov Vasiliy wrote: > put_user() return code was not checked for errors. To simplify the code > fill local struct dt3155_read with data and copy it with single > copy_to_user() call. > > Signed-off-by: Kulikov Vasiliy > --- > drivers/staging/dt3155/dt3155_drv.c | 17 ++++++++--------- > 1 files changed, 8 insertions(+), 9 deletions(-) > > diff --git a/drivers/staging/dt3155/dt3155_drv.c b/drivers/staging/dt3155/dt3155_drv.c > index 7316996..4013f09 100644 > --- a/drivers/staging/dt3155/dt3155_drv.c > +++ b/drivers/staging/dt3155/dt3155_drv.c > @@ -745,10 +745,11 @@ static ssize_t dt3155_read(struct file *filep, char __user *buf, > struct dt3155_status *dts = &dt3155_status[minor]; > struct dt3155_fbuffer *fb = &dts->fbuffer; > struct frame_info *frame_info; > + struct dt3155_read dt_read; > > /* TODO: this should check the error flag and */ > /* return an error on hardware failures */ > - if (count != sizeof(struct dt3155_read)) > + if (count != sizeof(dt_read)) I believe that sizeof(struct dt3155_read) is preferred, so this change isn't needed and sizeof(struct dt3155_read) should be used below (three times). > { > printk(KERN_INFO "DT3155 ERROR (NJC): count is not right\n"); > return -EINVAL; > @@ -797,17 +798,15 @@ static ssize_t dt3155_read(struct file *filep, char __user *buf, > > /* make this an offset */ > offset = frame_info->addr - dts->mem_addr; > + dt_read.offset = offset; > + dt_read.frame_seq = fb->frame_count; > + dt_read.state = dts->state; > + memcpy(&dt_read.frame_info, frame_info, sizeof(frame_info)); > > - put_user(offset, (unsigned int __user *)buf); > - buf += sizeof(u32); > - put_user(fb->frame_count, (unsigned int __user *)buf); > - buf += sizeof(u32); > - put_user(dts->state, (unsigned int __user *)buf); > - buf += sizeof(u32); > - if (copy_to_user(buf, frame_info, sizeof(*frame_info))) > + if (copy_to_user(buf, &dt_read, sizeof(dt_read))) > return -EFAULT; > > - return sizeof(struct dt3155_read); > + return sizeof(dt_read); > } > > static unsigned int dt3155_poll (struct file * filp, poll_table *wait) > -- > 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/