linux-kernel - Re: 回复: [PATCH] usb: replace snprintf in show functions with sysfs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <YWaFx3zMlsbWQQ6S@kroah.com>
Date:   Wed, 13 Oct 2021 09:07:51 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     王擎 <wangqing@...o.com>
Cc:     "linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: 回复: [PATCH] usb: replace
 snprintf in show functions with sysfs_emit

On Wed, Oct 13, 2021 at 06:52:53AM +0000, 王擎 wrote:
>  
> >> On Tue, Oct 12, 2021 at 08:27:47PM -0700, Qing Wang wrote:
> >> coccicheck complains about the use of snprintf() in sysfs show functions.
> >> 
> >> Fix the following coccicheck warning:
> >> drivers/usb/core/sysfs.c:730:8-16: WARNING: use scnprintf or sprintf.
> >> drivers/usb/core/sysfs.c:921:8-16: WARNING: use scnprintf or sprintf.
> >> 
> >> Use sysfs_emit instead of scnprintf or sprintf makes more sense.
> >> 
> >> Signed-off-by: Qing Wang <wangqing@...o.com>
> >> ---
> >>  drivers/usb/core/sysfs.c | 4 ++--
> >>  1 file changed, 2 insertions(+), 2 deletions(-)
> >> 
> >> diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
> >> index fa2e49d..6387c0d 100644
> >> --- a/drivers/usb/core/sysfs.c
> >> +++ b/drivers/usb/core/sysfs.c
> >> @@ -727,7 +727,7 @@ static ssize_t authorized_show(struct device *dev,
> >>                               struct device_attribute *attr, char *buf)
> >>  {
> >>        struct usb_device *usb_dev = to_usb_device(dev);
> >> -     return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
> >> +     return sysfs_emit(buf, "%u\n", usb_dev->authorized);
> >>  }
> >>  
> >>  /*
> >> @@ -918,7 +918,7 @@ static ssize_t authorized_default_show(struct device *dev,
> >>        struct usb_hcd *hcd;
> >>  
> >>        hcd = bus_to_hcd(usb_bus);
> >> -     return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy);
> >> +     return sysfs_emit(buf, "%u\n", hcd->dev_policy);
> >>  }
> >>  
> >>  static ssize_t authorized_default_store(struct device *dev,
> >> -- 
> >> 2.7.4
> >> 
> > 
> > If you are going to change this file, you should do this for all of the
> > sysfs show functions in this file, not just 2 of them, right?  Please
> > change this patch to do that.
> >
> > thanks,
> > 
> > greg k-h
> 
> Only these 2 snprintf need to be modified, other show functions
> used sprintf do not need to modify.

I do not think you understand the change you are trying to make here.

Either the whole file should use the same api, or just leave it as-is as
it obviously works properly today :)

thanks,

greg k-h