From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 6 Dec 2012 12:13:26 -0800 From: Greg KH To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, stable , Ingo Molnar , Andrew Morton , Thomas Gleixner , Frederic Weisbecker Subject: Re: [v3.0 stable version][PATCH 1/2] ring-buffer: Fix NULL pointer if rb_set_head_page() fails Message-ID: <20121206201326.GA10874@kroah.com> References: <20121130161238.909829067@goodmis.org> <20121130161333.983378567@goodmis.org> <1354292203.6276.159.camel@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1354292203.6276.159.camel@gandalf.local.home> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Fri, Nov 30, 2012 at 11:16:43AM -0500, Steven Rostedt wrote: > The function rb_set_head_page() searches the list of ring buffer > pages for a the page that has the HEAD page flag set. If it does > not find it, it will do a WARN_ON(), disable the ring buffer and > return NULL, as this should never happen. > > But if this bug happens to happen, not all callers of this function > can handle a NULL pointer being returned from it. That needs to be > fixed. > > Cc: stable@vger.kernel.org # 3.0+ > Signed-off-by: Steven Rostedt > --- > kernel/trace/ring_buffer.c | 9 +++++++-- > 1 files changed, 7 insertions(+), 2 deletions(-) I don't understand why you sent these to stable@ right now, I don't see them in Linus's tree, so why are they needed here? Care to resend them when they hit Linus's tree? thanks, greg k-h