From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 902EB1171A for ; Mon, 21 Aug 2023 20:06:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA1B4C433C7; Mon, 21 Aug 2023 20:06:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692648413; bh=PriA6zDK3soTxJ2EJUzuv+TuUa22NkLq0iVM4/w07bE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iDvMAeRJQaoQtufkBtnBQ6TmbWsW3Mx3T67X9TO+ynxk36qAtDMD3tDRT8AL6s+dd dG6RpQ6LXb3uKaHKwvZTd+unqM2JvWbsJA686ZYwx7acFPKbO1CphHgwdyh+SHanP+ d73Qk+J0LdoLcCC1051jGNr87hbcqcg8TtJQb1tw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+7456b5dcf65111553320@syzkaller.appspotmail.com, Leon Romanovsky , Aaron Conole , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.4 167/234] net: openvswitch: reject negative ifindex Date: Mon, 21 Aug 2023 21:42:10 +0200 Message-ID: <20230821194136.213325738@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230821194128.754601642@linuxfoundation.org> References: <20230821194128.754601642@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Jakub Kicinski [ Upstream commit a552bfa16bab4ce901ee721346a28c4e483f4066 ] Recent changes in net-next (commit 759ab1edb56c ("net: store netdevs in an xarray")) refactored the handling of pre-assigned ifindexes and let syzbot surface a latent problem in ovs. ovs does not validate ifindex, making it possible to create netdev ports with negative ifindex values. It's easy to repro with YNL: $ ./cli.py --spec netlink/specs/ovs_datapath.yaml \ --do new \ --json '{"upcall-pid": 1, "name":"my-dp"}' $ ./cli.py --spec netlink/specs/ovs_vport.yaml \ --do new \ --json '{"upcall-pid": "00000001", "name": "some-port0", "dp-ifindex":3,"ifindex":4294901760,"type":2}' $ ip link show -65536: some-port0: mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 7a:48:21:ad:0b:fb brd ff:ff:ff:ff:ff:ff ... Validate the inputs. Now the second command correctly returns: $ ./cli.py --spec netlink/specs/ovs_vport.yaml \ --do new \ --json '{"upcall-pid": "00000001", "name": "some-port0", "dp-ifindex":3,"ifindex":4294901760,"type":2}' lib.ynl.NlError: Netlink error: Numerical result out of range nl_len = 108 (92) nl_flags = 0x300 nl_type = 2 error: -34 extack: {'msg': 'integer out of range', 'unknown': [[type:4 len:36] b'\x0c\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x0c\x00\x03\x00\xff\xff\xff\x7f\x00\x00\x00\x00\x08\x00\x01\x00\x08\x00\x00\x00'], 'bad-attr': '.ifindex'} Accept 0 since it used to be silently ignored. Fixes: 54c4ef34c4b6 ("openvswitch: allow specifying ifindex of new interfaces") Reported-by: syzbot+7456b5dcf65111553320@syzkaller.appspotmail.com Reviewed-by: Leon Romanovsky Reviewed-by: Aaron Conole Link: https://lore.kernel.org/r/20230814203840.2908710-1-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/openvswitch/datapath.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index a6d2a0b1aa21e..3d7a91e64c88f 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1829,7 +1829,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info) parms.port_no = OVSP_LOCAL; parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID]; parms.desired_ifindex = a[OVS_DP_ATTR_IFINDEX] - ? nla_get_u32(a[OVS_DP_ATTR_IFINDEX]) : 0; + ? nla_get_s32(a[OVS_DP_ATTR_IFINDEX]) : 0; /* So far only local changes have been made, now need the lock. */ ovs_lock(); @@ -2049,7 +2049,7 @@ static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = { [OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 }, [OVS_DP_ATTR_MASKS_CACHE_SIZE] = NLA_POLICY_RANGE(NLA_U32, 0, PCPU_MIN_UNIT_SIZE / sizeof(struct mask_cache_entry)), - [OVS_DP_ATTR_IFINDEX] = {.type = NLA_U32 }, + [OVS_DP_ATTR_IFINDEX] = NLA_POLICY_MIN(NLA_S32, 0), }; static const struct genl_small_ops dp_datapath_genl_ops[] = { @@ -2302,7 +2302,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info) parms.port_no = port_no; parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID]; parms.desired_ifindex = a[OVS_VPORT_ATTR_IFINDEX] - ? nla_get_u32(a[OVS_VPORT_ATTR_IFINDEX]) : 0; + ? nla_get_s32(a[OVS_VPORT_ATTR_IFINDEX]) : 0; vport = new_vport(&parms); err = PTR_ERR(vport); @@ -2539,7 +2539,7 @@ static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = { [OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 }, [OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_UNSPEC }, [OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED }, - [OVS_VPORT_ATTR_IFINDEX] = { .type = NLA_U32 }, + [OVS_VPORT_ATTR_IFINDEX] = NLA_POLICY_MIN(NLA_S32, 0), [OVS_VPORT_ATTR_NETNSID] = { .type = NLA_S32 }, [OVS_VPORT_ATTR_UPCALL_STATS] = { .type = NLA_NESTED }, }; -- 2.40.1