Re: [PATCH v3 net-next 1/4] tcp: ULP infrastructure

["Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>]

On Mon, Jun 26, 2017 at 07:30:19AM -0700, Dave Watson wrote:
>On 06/25/17 02:42 AM, Levin, Alexander (Sasha Levin) wrote:
>> On Wed, Jun 14, 2017 at 11:37:14AM -0700, Dave Watson wrote:
>> >Add the infrustructure for attaching Upper Layer Protocols (ULPs) over TCP
>> >sockets. Based on a similar infrastructure in tcp_cong.  The idea is that any
>> >ULP can add its own logic by changing the TCP proto_ops structure to its own
>> >methods.
>> >
>> >Example usage:
>> >
>> >setsockopt(sock, SOL_TCP, TCP_ULP, "tls", sizeof("tls"));
>> >
>> >modules will call:
>> >tcp_register_ulp(&tcp_tls_ulp_ops);
>> >
>> >to register/unregister their ulp, with an init function and name.
>> >
>> >A list of registered ulps will be returned by tcp_get_available_ulp, which is
>> >hooked up to /proc.  Example:
>> >
>> >$ cat /proc/sys/net/ipv4/tcp_available_ulp
>> >tls
>> >
>> >There is currently no functionality to remove or chain ULPs, but
>> >it should be possible to add these in the future if needed.
>> >
>> >Signed-off-by: Boris Pismenny <borisp@mellanox.com>
>> >Signed-off-by: Dave Watson <davejwatson@fb.com>
>>
>> Hey Dave,
>>
>> I'm seeing the following while fuzzing, which was bisected to this commit:
>>
>> ==================================================================
>> BUG: KASAN: null-ptr-deref in copy_to_user include/linux/uaccess.h:168 [inline]
>> BUG: KASAN: null-ptr-deref in do_tcp_getsockopt.isra.33+0x24f/0x1e30 net/ipv4/tcp.c:3057
>> Read of size 4 at addr 0000000000000020 by task syz-executor1/15452
>
>At a glance, this looks like it was fixed already by
>
>https://www.mail-archive.com/netdev@vger.kernel.org/msg175226.html
>
>Can you recheck with that patch, or verify that you already have it?
>Thanks.

I've already tried this patch, it doesn't fix the issue I've reported.

-- 

Thanks,
Sasha