The "ivm->vf" variable is a u32, but the problem is that a number of drivers cast it to an int and then forget to check for negatives. An example of this is in the cxgb4 driver. drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c 2890 static int cxgb4_mgmt_get_vf_config(struct net_device *dev, 2891 int vf, struct ifla_vf_info *ivi) ^^^^^^ 2892 { 2893 struct port_info *pi = netdev_priv(dev); 2894 struct adapter *adap = pi->adapter; 2895 struct vf_info *vfinfo; 2896 2897 if (vf >= adap->num_vfs) ^^^^^^^^^^^^^^^^^^^ 2898 return -EINVAL; 2899 vfinfo = &adap->vfinfo[vf]; ^^^^^^^^^^^^^^^^^^^^^^^^^^ There are 48 functions affected. drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c:8435 hclge_set_vf_vlan_filter() warn: can 'vfid' underflow 's32min-2147483646' drivers/net/ethernet/freescale/enetc/enetc_pf.c:377 enetc_pf_set_vf_mac() warn: can 'vf' underflow 's32min-2147483646' drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c:2899 cxgb4_mgmt_get_vf_config() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c:2960 cxgb4_mgmt_set_vf_rate() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c:3019 cxgb4_mgmt_set_vf_rate() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c:3038 cxgb4_mgmt_set_vf_vlan() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c:3086 cxgb4_mgmt_set_vf_link_state() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/chelsio/cxgb/cxgb2.c:791 get_eeprom() warn: can 'i' underflow 's32min-(-4),0,4-s32max' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:82 bnxt_set_vf_spoofchk() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:164 bnxt_set_vf_trust() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:186 bnxt_get_vf_config() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:228 bnxt_set_vf_mac() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:264 bnxt_set_vf_vlan() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:293 bnxt_set_vf_bw() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c:333 bnxt_set_vf_link_state() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/broadcom/bnx2x/bnx2x_sriov.c:2595 bnx2x_vf_op_prep() warn: can 'vfidx' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_sriov.c:2595 bnx2x_vf_op_prep() warn: can 'vfidx' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c:2281 bnx2x_post_vf_bulletin() warn: can 'vf' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c:2285 bnx2x_post_vf_bulletin() warn: can 'vf' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c:2286 bnx2x_post_vf_bulletin() warn: can 'vf' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c:2292 bnx2x_post_vf_bulletin() warn: can 'vf' underflow 's32min-63' drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c:2297 bnx2x_post_vf_bulletin() warn: can 'vf' underflow 's32min-63' drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c:1832 qlcnic_sriov_set_vf_mac() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c:1864 qlcnic_sriov_set_vf_tx_rate() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c:1937 qlcnic_sriov_set_vf_vlan() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c:2005 qlcnic_sriov_get_vf_config() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c:2036 qlcnic_sriov_set_vf_spoofchk() warn: can 'vf' underflow 's32min-254' drivers/net/ethernet/emulex/benet/be_main.c:1914 be_get_vf_config() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/emulex/benet/be_main.c:1915 be_get_vf_config() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/emulex/benet/be_main.c:1922 be_set_vf_tvt() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/emulex/benet/be_main.c:1951 be_clear_vf_tvt() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/emulex/benet/be_main.c:2063 be_set_vf_tx_rate() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/emulex/benet/be_main.c:2091 be_set_vf_link_state() warn: can 'vf' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:2609 ice_set_vf_port_vlan() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:3050 ice_get_vf_cfg() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:3103 ice_set_vf_spoofchk() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:3181 ice_set_vf_mac() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:3237 ice_set_vf_trust() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c:3286 ice_set_vf_link_state() warn: can 'vf_id' underflow 's32min-65534' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:3919 i40e_validate_vf() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:3957 i40e_ndo_set_vf_mac() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4104 i40e_ndo_set_vf_port_vlan() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4263 i40e_ndo_set_vf_bw() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4309 i40e_ndo_get_vf_config() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4371 i40e_ndo_set_vf_link_state() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4441 i40e_ndo_set_vf_spoofchk() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4441 i40e_ndo_set_vf_spoofchk() warn: can 'vf_id' underflow 's32min-2147483646' drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c:4504 i40e_ndo_set_vf_trust() warn: can 'vf_id' underflow 's32min-2147483646' Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- I reported this bug to the linux-rdma mailing list in April and this patch wasn't considered very elegant. I can see how that's true. The developer offered to write a fix which would update all the drivers to use u32 throughout. I reminded him in September that this bug still needs to be fixed. I think there may be security implications and this patch is easy to backport to stable kernels so in that sense, it might be a better approach. Also this patch might prevent underflows in future drivers. net/core/rtnetlink.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 000eddb1207d..9f7aa448bd11 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2251,6 +2251,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_MAC]) { struct ifla_vf_mac *ivm = nla_data(tb[IFLA_VF_MAC]); + if (ivm->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_mac) err = ops->ndo_set_vf_mac(dev, ivm->vf, @@ -2262,6 +2264,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_VLAN]) { struct ifla_vf_vlan *ivv = nla_data(tb[IFLA_VF_VLAN]); + if (ivv->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_vlan) err = ops->ndo_set_vf_vlan(dev, ivv->vf, ivv->vlan, @@ -2294,6 +2298,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (len == 0) return -EINVAL; + if (ivvl[0]->vf >= INT_MAX) + return -EINVAL; err = ops->ndo_set_vf_vlan(dev, ivvl[0]->vf, ivvl[0]->vlan, ivvl[0]->qos, ivvl[0]->vlan_proto); if (err < 0) @@ -2304,6 +2310,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) struct ifla_vf_tx_rate *ivt = nla_data(tb[IFLA_VF_TX_RATE]); struct ifla_vf_info ivf; + if (ivt->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_get_vf_config) err = ops->ndo_get_vf_config(dev, ivt->vf, &ivf); @@ -2322,6 +2330,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_RATE]) { struct ifla_vf_rate *ivt = nla_data(tb[IFLA_VF_RATE]); + if (ivt->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_rate) err = ops->ndo_set_vf_rate(dev, ivt->vf, @@ -2334,6 +2344,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_SPOOFCHK]) { struct ifla_vf_spoofchk *ivs = nla_data(tb[IFLA_VF_SPOOFCHK]); + if (ivs->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_spoofchk) err = ops->ndo_set_vf_spoofchk(dev, ivs->vf, @@ -2345,6 +2357,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_LINK_STATE]) { struct ifla_vf_link_state *ivl = nla_data(tb[IFLA_VF_LINK_STATE]); + if (ivl->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_link_state) err = ops->ndo_set_vf_link_state(dev, ivl->vf, @@ -2358,6 +2372,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) err = -EOPNOTSUPP; ivrssq_en = nla_data(tb[IFLA_VF_RSS_QUERY_EN]); + if (ivrssq_en->vf >= INT_MAX) + return -EINVAL; if (ops->ndo_set_vf_rss_query_en) err = ops->ndo_set_vf_rss_query_en(dev, ivrssq_en->vf, ivrssq_en->setting); @@ -2368,6 +2384,8 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_TRUST]) { struct ifla_vf_trust *ivt = nla_data(tb[IFLA_VF_TRUST]); + if (ivt->vf >= INT_MAX) + return -EINVAL; err = -EOPNOTSUPP; if (ops->ndo_set_vf_trust) err = ops->ndo_set_vf_trust(dev, ivt->vf, ivt->setting); @@ -2378,15 +2396,18 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb) if (tb[IFLA_VF_IB_NODE_GUID]) { struct ifla_vf_guid *ivt = nla_data(tb[IFLA_VF_IB_NODE_GUID]); + if (ivt->vf >= INT_MAX) + return -EINVAL; if (!ops->ndo_set_vf_guid) return -EOPNOTSUPP; - return handle_vf_guid(dev, ivt, IFLA_VF_IB_NODE_GUID); } if (tb[IFLA_VF_IB_PORT_GUID]) { struct ifla_vf_guid *ivt = nla_data(tb[IFLA_VF_IB_PORT_GUID]); + if (ivt->vf >= INT_MAX) + return -EINVAL; if (!ops->ndo_set_vf_guid) return -EOPNOTSUPP; -- 2.11.0