All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Brownell <david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org>
To: Greg KH <greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
Cc: i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
Subject: Re: class_for_each_device() oops
Date: Wed, 23 Jul 2008 16:43:47 -0700	[thread overview]
Message-ID: <200807231643.47802.david-b@pacbell.net> (raw)
In-Reply-To: <20080723231859.GB30234-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>

On Wednesday 23 July 2008, Greg KH wrote:
> > In this case adding 
> > 
> >       if (!class->p)
> >               return -EINVAL;
> > 
> > at the top of class_for_each_device() would prevent such
> > oopses from ever happening.
> 
> Makes sense, care to send a real patch for this?

Here you go ... I noticed another place with the same
type of oops-affinity, and fixed that too.

===== CUT HERE
From: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>

Anti-oops medicine for the class iterators ... the oops was
observed when a class was implicitly referenced before it
was initialized.

Signed-off-by: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>
---
 drivers/base/class.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/base/class.c	2008-07-22 15:27:52.000000000 -0700
+++ b/drivers/base/class.c	2008-07-23 16:39:58.000000000 -0700
@@ -292,7 +292,7 @@ int class_for_each_device(struct class *
 	struct device *dev;
 	int error = 0;
 
-	if (!class)
+	if (!class || !class->p)
 		return -EINVAL;
 	mutex_lock(&class->p->class_mutex);
 	list_for_each_entry(dev, &class->p->class_devices, node) {
@@ -341,7 +341,7 @@ struct device *class_find_device(struct 
 	struct device *dev;
 	int found = 0;
 
-	if (!class)
+	if (!class || !class->p)
 		return NULL;
 
 	mutex_lock(&class->p->class_mutex);


_______________________________________________
i2c mailing list
i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
http://lists.lm-sensors.org/mailman/listinfo/i2c

      parent reply	other threads:[~2008-07-23 23:43 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-23 23:06 class_for_each_device() oops David Brownell
     [not found] ` <200807231606.48016.david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org>
2008-07-23 23:18   ` Greg KH
     [not found]     ` <20080723231859.GB30234-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2008-07-23 23:43       ` David Brownell [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=200807231643.47802.david-b@pacbell.net \
    --to=david-b-ybekhbn/0ldr7s880joybq@public.gmane.org \
    --cc=greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org \
    --cc=i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.