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Date:   Fri, 17 Nov 2023 18:47:02 +0530
From:   Siddh Raman Pant <code@siddh.me>
To:     "Krzysztof Kozlowski" <krzysztof.kozlowski@linaro.org>
Cc:     "davem" <davem@davemloft.net>, "edumazet" <edumazet@google.com>,
        "kuba" <kuba@kernel.org>, "pabeni" <pabeni@redhat.com>,
        "linux-kernel" <linux-kernel@vger.kernel.org>,
        "netdev" <netdev@vger.kernel.org>,
        "syzkaller-bugs" <syzkaller-bugs@googlegroups.com>,
        "syzbot+bbe84a4010eeea00982d" 
        <syzbot+bbe84a4010eeea00982d@syzkaller.appspotmail.com>
Message-ID: <18bdd6d7d1e.f8bd3007064.1218727710101871071@siddh.me>
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Subject: Re: [syzbot] [net?] [nfc?] KASAN: slab-use-after-free Read in
 nfc_alloc_send_skb
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On Fri, 17 Nov 2023 18:18:56 +0530, Krzysztof Kozlowski wrote:
> Any checks would need to have proper locking. Or at least barriers...
> Adding checks without locks usually does not solve race conditions.

Yes of course. I just wanted to put whatever I tested out there.

> Other start is proper ref counting, so the structures are not released
> too early. We have several bugs like this in NFC before, so you can take
> a look at their fixes.

Sure.

Thanks,
Siddh