Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Michael Ellerman <mpe@ellerman.id.au>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk,
        ajd@linux.ibm.com,
        syzbot+1e925b4b836afe85a1c6@syzkaller-ppc64.appspotmail.com,
        syzbot+587b2421926808309d21@syzkaller-ppc64.appspotmail.com,
        syzbot+58320b7171734bf79d26@syzkaller.appspotmail.com,
        syzbot+d6074fb08bdb2e010520@syzkaller.appspotmail.com,
        Guenter Roeck <linux@roeck-us.net>,
        Daniel Axtens <dja@axtens.net>,
        Salvatore Bonaccorso <carnil@debian.org>,
        David Rientjes <rientjes@google.com>
Subject: Re: [PATCH v2] relay: handle alloc_percpu returning NULL in relay_open
In-Reply-To: <87ftbo232s.fsf@dja-thinkpad.axtens.net>
References: <20191219121256.26480-1-dja@axtens.net> <alpine.DEB.2.21.1912201100400.68407@chino.kir.corp.google.com> <20200521152514.GA2868125@eldamar.local> <87ftbo232s.fsf@dja-thinkpad.axtens.net>
Date:   Tue, 26 May 2020 13:25:36 +1000
Message-ID: <878shffkcv.fsf@mpe.ellerman.id.au>
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

[ + akpm ]

Daniel Axtens <dja@axtens.net> writes:
>>> > Check if alloc_percpu returns NULL.
>>> > 
>>> > This was found by syzkaller both on x86 and powerpc, and the reproducer
>>> > it found on powerpc is capable of hitting the issue as an unprivileged
>>> > user.
>>> > 
>>> > Fixes: 017c59c042d0 ("relay: Use per CPU constructs for the relay channel buffer pointers")
>>> > Reported-by: syzbot+1e925b4b836afe85a1c6@syzkaller-ppc64.appspotmail.com
>>> > Reported-by: syzbot+587b2421926808309d21@syzkaller-ppc64.appspotmail.com
>>> > Reported-by: syzbot+58320b7171734bf79d26@syzkaller.appspotmail.com
>>> > Reported-by: syzbot+d6074fb08bdb2e010520@syzkaller.appspotmail.com
>>> > Cc: Akash Goel <akash.goel@intel.com>
>>> > Cc: Andrew Donnellan <ajd@linux.ibm.com> # syzkaller-ppc64
>>> > Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
>>> > Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
>>> > Cc: stable@vger.kernel.org # v4.10+
>>> > Signed-off-by: Daniel Axtens <dja@axtens.net>
>>> 
>>> Acked-by: David Rientjes <rientjes@google.com>
>>
>> It looks this one was never applied (which relates to CVE-2019-19462,
>> as pointed by Guenter in 20191223163610.GA32267@roeck-us.net).
>>
>> Whas this lost or are there any issues pending?
>
> I'm not aware of any pending issues.
>
> (But, if anyone does have any objections I'm happy to revise the patch.)

It looks like kernel/relay.c is lacking a maintainer?

Andrew are you able to pick this up for v5.8? It's pretty obviously
correct, and has David's ack.

Original is here if that helps:
  https://lore.kernel.org/lkml/20191219121256.26480-1-dja@axtens.net/


cheers