From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53482 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753273AbdHKQU5 (ORCPT ); Fri, 11 Aug 2017 12:20:57 -0400 Subject: Patch "packet: fix tp_reserve race in packet_set_ring" has been added to the 4.12-stable tree To: willemb@google.com, andreyknvl@google.com, davem@davemloft.net, gregkh@linuxfoundation.org Cc: , From: Date: Fri, 11 Aug 2017 09:20:53 -0700 Message-ID: <150246845317673@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled packet: fix tp_reserve race in packet_set_ring 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: packet-fix-tp_reserve-race-in-packet_set_ring.patch and it can be found in the queue-4.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Fri Aug 11 09:09:38 PDT 2017 From: Willem de Bruijn Date: Thu, 10 Aug 2017 12:41:58 -0400 Subject: packet: fix tp_reserve race in packet_set_ring From: Willem de Bruijn [ Upstream commit c27927e372f0785f3303e8fad94b85945e2c97b7 ] Updates to tp_reserve can race with reads of the field in packet_set_ring. Avoid this by holding the socket lock during updates in setsockopt PACKET_RESERVE. This bug was discovered by syzkaller. Fixes: 8913336a7e8d ("packet: add PACKET_RESERVE sockopt") Reported-by: Andrey Konovalov Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/packet/af_packet.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3705,14 +3705,19 @@ packet_setsockopt(struct socket *sock, i if (optlen != sizeof(val)) return -EINVAL; - if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) - return -EBUSY; if (copy_from_user(&val, optval, sizeof(val))) return -EFAULT; if (val > INT_MAX) return -EINVAL; - po->tp_reserve = val; - return 0; + lock_sock(sk); + if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) { + ret = -EBUSY; + } else { + po->tp_reserve = val; + ret = 0; + } + release_sock(sk); + return ret; } case PACKET_LOSS: { Patches currently in stable-queue which might be from willemb@google.com are queue-4.12/net-avoid-skb_warn_bad_offload-false-positives-on-ufo.patch queue-4.12/packet-fix-tp_reserve-race-in-packet_set_ring.patch queue-4.12/udp-consistently-apply-ufo-or-fragmentation.patch