Re: Patch "bridge: mdb: fix leak on complete_info ptr on fail path" has been added to the 4.12-stable tree

Eduardo Valentin
2017-07-17T18:32:12Z

Greg,

On Mon, Jul 17, 2017 at 06:52:21PM +0200, gregkh@linuxfoundation.org wrote:
>
> This is a note to let you know that I've just added the patch titled
>
> bridge: mdb: fix leak on complete_info ptr on fail path
>
> to the 4.12-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>
> The filename of the patch is:
> bridge-mdb-fix-leak-on-complete_info-ptr-on-fail-path.patch
> and it can be found in the queue-4.12 subdirectory.

Can we get this patch also in the 4.9.y queue?

Thanks in advance.

>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
>
>
> From foo@baz Mon Jul 17 18:46:41 CEST 2017
> From: Eduardo Valentin <eduval@amazon.com>
> Date: Tue, 11 Jul 2017 14:55:12 -0700
> Subject: bridge: mdb: fix leak on complete_info ptr on fail path
>
> From: Eduardo Valentin <eduval@amazon.com>
>
>
> [ Upstream commit 1bfb159673957644951ab0a8d2aec44b93ddb1ae ]
>
> We currently get the following kmemleak report:
> unreferenced object 0xffff8800039d9820 (size 32):
> comm "softirq", pid 0, jiffies 4295212383 (age 792.416s)
> hex dump (first 32 bytes):
> 00 0c e0 03 00 88 ff ff ff 02 00 00 00 00 00 00 ................
> 00 00 00 01 ff 11 00 02 86 dd 00 00 ff ff ff ff ................
> backtrace:
> [<ffffffff8152b4aa>] kmemleak_alloc+0x4a/0xa0
> [<ffffffff811d8ec8>] kmem_cache_alloc_trace+0xb8/0x1c0
> [<ffffffffa0389683>] __br_mdb_notify+0x2a3/0x300 [bridge]
> [<ffffffffa038a0ce>] br_mdb_notify+0x6e/0x70 [bridge]
> [<ffffffffa0386479>] br_multicast_add_group+0x109/0x150 [bridge]
> [<ffffffffa0386518>] br_ip6_multicast_add_group+0x58/0x60 [bridge]
> [<ffffffffa0387fb5>] br_multicast_rcv+0x1d5/0xdb0 [bridge]
> [<ffffffffa037d7cf>] br_handle_frame_finish+0xcf/0x510 [bridge]
> [<ffffffffa03a236b>] br_nf_hook_thresh.part.27+0xb/0x10 [br_netfilter]
> [<ffffffffa03a3738>] br_nf_hook_thresh+0x48/0xb0 [br_netfilter]
> [<ffffffffa03a3fb9>] br_nf_pre_routing_finish_ipv6+0x109/0x1d0 [br_netfilter]
> [<ffffffffa03a4400>] br_nf_pre_routing_ipv6+0xd0/0x14c [br_netfilter]
> [<ffffffffa03a3c27>] br_nf_pre_routing+0x197/0x3d0 [br_netfilter]
> [<ffffffff814a2952>] nf_iterate+0x52/0x60
> [<ffffffff814a29bc>] nf_hook_slow+0x5c/0xb0
> [<ffffffffa037ddf4>] br_handle_frame+0x1a4/0x2c0 [bridge]
>
> This happens when switchdev_port_obj_add() fails. This patch
> frees complete_info object in the fail path.
>
> Reviewed-by: Vallish Vaidyeshwara <vallish@amazon.com>
> Signed-off-by: Eduardo Valentin <eduval@amazon.com>
> Signed-off-by: David S. Miller <davem@davemloft.net>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> net/bridge/br_mdb.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> --- a/net/bridge/br_mdb.c
> +++ b/net/bridge/br_mdb.c
> @@ -323,7 +323,8 @@ static void __br_mdb_notify(struct net_d
> __mdb_entry_to_br_ip(entry, &complete_info->ip);
> mdb.obj.complete_priv = complete_info;
> mdb.obj.complete = br_mdb_complete;
> - switchdev_port_obj_add(port_dev, &mdb.obj);
> + if (switchdev_port_obj_add(port_dev, &mdb.obj))
> + kfree(complete_info);
> }
> } else if (port_dev && type == RTM_DELMDB) {
> switchdev_port_obj_del(port_dev, &mdb.obj);
>
>
> Patches currently in stable-queue which might be from eduval@amazon.com are
>
> queue-4.12/bridge-mdb-fix-leak-on-complete_info-ptr-on-fail-path.patch

--
All the best,
Eduardo Valentin