ice: Add a boundary check in ice_xsk_umem()
authorKrzysztof Kazimierczak <krzysztof.kazimierczak@intel.com>
Thu, 12 Dec 2019 11:13:06 +0000 (03:13 -0800)
committerJeff Kirsher <jeffrey.t.kirsher@intel.com>
Sat, 4 Jan 2020 00:08:33 +0000 (16:08 -0800)
In ice_xsk_umem(), variable qid which is later used as an array index,
is not validated for a possible boundary exceedance. Because of that,
a calling function might receive an invalid address, which causes
general protection fault when dereferenced.

To address this, add a boundary check to see if qid is greater than the
size of a UMEM array. Also, don't let user change vsi->num_xsk_umems
just by trying to setup a second UMEM if its value is already set up
(i.e. UMEM region has already been allocated for this VSI).

While at it, make sure that ring->zca.free pointer is always zeroed out
if there is no UMEM on a specified ring.

Signed-off-by: Krzysztof Kazimierczak <krzysztof.kazimierczak@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
drivers/net/ethernet/intel/ice/ice.h
drivers/net/ethernet/intel/ice/ice_base.c
drivers/net/ethernet/intel/ice/ice_xsk.c

index 1376219..cb10abb 100644 (file)
@@ -465,12 +465,13 @@ static inline void ice_set_ring_xdp(struct ice_ring *ring)
 static inline struct xdp_umem *ice_xsk_umem(struct ice_ring *ring)
 {
        struct xdp_umem **umems = ring->vsi->xsk_umems;
-       int qid = ring->q_index;
+       u16 qid = ring->q_index;
 
        if (ice_ring_is_xdp(ring))
                qid -= ring->vsi->num_xdp_txq;
 
-       if (!umems || !umems[qid] || !ice_is_xdp_ena_vsi(ring->vsi))
+       if (qid >= ring->vsi->num_xsk_umems || !umems || !umems[qid] ||
+           !ice_is_xdp_ena_vsi(ring->vsi))
                return NULL;
 
        return umems[qid];
index d4559d4..25f2e0f 100644 (file)
@@ -326,6 +326,7 @@ int ice_setup_rx_ctx(struct ice_ring *ring)
                        dev_info(&vsi->back->pdev->dev, "Registered XDP mem model MEM_TYPE_ZERO_COPY on Rx ring %d\n",
                                 ring->q_index);
                } else {
+                       ring->zca.free = NULL;
                        if (!xdp_rxq_info_is_reg(&ring->xdp_rxq))
                                xdp_rxq_info_reg(&ring->xdp_rxq,
                                                 ring->netdev,
index 0af1f0b..0e401f1 100644 (file)
@@ -414,7 +414,8 @@ ice_xsk_umem_enable(struct ice_vsi *vsi, struct xdp_umem *umem, u16 qid)
        if (vsi->type != ICE_VSI_PF)
                return -EINVAL;
 
-       vsi->num_xsk_umems = min_t(u16, vsi->num_rxq, vsi->num_txq);
+       if (!vsi->num_xsk_umems)
+               vsi->num_xsk_umems = min_t(u16, vsi->num_rxq, vsi->num_txq);
        if (qid >= vsi->num_xsk_umems)
                return -EINVAL;