Date: Fri, 20 Apr 2018 09:45:07 -0700
From: Mark Greer <mgreer@animalcreek.com>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Amit Pundir <amit.pundir@linaro.org>,
        lkml <linux-kernel@vger.kernel.org>,
        linux-wireless@vger.kernel.org,
        Samuel Ortiz <sameo@linux.intel.com>,
        Christophe Ricard <christophe.ricard@gmail.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        John Stultz <john.stultz@linaro.org>,
        Dmitry Shmidt <dimitrysh@google.com>,
        Todd Kjos <tkjos@google.com>,
        Android Kernel Team <kernel-team@android.com>,
        Suren Baghdasaryan <surenb@google.com>
Subject: Re: [RESEND][PATCH 2/4] NFC: st21nfca: Fix memory OOB and leak
 issues in connectivity events handler
Message-ID: <20180420164507.GA22666@animalcreek.com> (sfid-20180420_184525_646234_F77B4F73)
References: <1524045904-7005-1-git-send-email-amit.pundir@linaro.org>
 <1524045904-7005-3-git-send-email-amit.pundir@linaro.org>
 <1524227986.21176.467.camel@linux.intel.com>
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Sender: linux-wireless-owner@vger.kernel.org

On Fri, Apr 20, 2018 at 03:39:46PM +0300, Andy Shevchenko wrote:
> On Wed, 2018-04-18 at 15:35 +0530, Amit Pundir wrote:
> 
> >  		if (skb->data[transaction->aid_len + 2] !=
> > -		    NFC_EVT_TRANSACTION_PARAMS_TAG)
> > +		    NFC_EVT_TRANSACTION_PARAMS_TAG ||
> > +		    skb->len < transaction->aid_len + transaction-
> > >params_len + 4) {
> 
> > +			devm_kfree(dev, transaction);
> 
> Oh, no.
> 
> This is not memory leak per se, this is bad choice of devm_ API where it
> should use plain kmalloc() / kfree().

Also, there is no check to see if the allocation worked at all.

Mark
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