diff mbox series

[net-next] vmxnet3: Remove buf_info from device accessible structures

Message ID 20210120021120.9579-1-doshir@vmware.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [net-next] vmxnet3: Remove buf_info from device accessible structures | expand

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Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 18 this patch: 15
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch warning WARNING: kfree(NULL) is safe and this check is probably not required WARNING: line length of 84 exceeds 80 columns
netdev/build_allmodconfig_warn success Errors and warnings before: 18 this patch: 15
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Ronak Doshi Jan. 20, 2021, 2:11 a.m. UTC 
From: Petr Vandrovec <petr@vmware.com>

vmxnet3: Remove buf_info from device accessible structures

buf_info structures in RX & TX queues are private driver data that
do not need to be visible to the device.  Although there is physical
address and length in the queue descriptor that points to these
structures, their layout is not standardized, and device never looks
at them.

So lets allocate these structures in non-DMA-able memory, and fill
physical address as all-ones and length as zero in the queue
descriptor.

That should alleviate worries brought by Martin Radev in
https://lists.osuosl.org/pipermail/intel-wired-lan/Week-of-Mon-20210104/022829.html
that malicious vmxnet3 device could subvert SVM/TDX guarantees.

Signed-off-by: Petr Vandrovec <petr@vmware.com>
Signed-off-by: Ronak Doshi <doshir@vmware.com>
---
 drivers/net/vmxnet3/vmxnet3_drv.c | 45 ++++++++++++++++-----------------------
 drivers/net/vmxnet3/vmxnet3_int.h |  2 --
 2 files changed, 18 insertions(+), 29 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 336504b7531d..8f5e1e363598 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -452,9 +452,7 @@  vmxnet3_tq_destroy(struct vmxnet3_tx_queue *tq,
 		tq->comp_ring.base = NULL;
 	}
 	if (tq->buf_info) {
-		dma_free_coherent(&adapter->pdev->dev,
-				  tq->tx_ring.size * sizeof(tq->buf_info[0]),
-				  tq->buf_info, tq->buf_info_pa);
+		kfree(tq->buf_info);
 		tq->buf_info = NULL;
 	}
 }
@@ -505,8 +503,6 @@  static int
 vmxnet3_tq_create(struct vmxnet3_tx_queue *tq,
 		  struct vmxnet3_adapter *adapter)
 {
-	size_t sz;
-
 	BUG_ON(tq->tx_ring.base || tq->data_ring.base ||
 	       tq->comp_ring.base || tq->buf_info);
 
@@ -534,11 +530,13 @@  vmxnet3_tq_create(struct vmxnet3_tx_queue *tq,
 		goto err;
 	}
 
-	sz = tq->tx_ring.size * sizeof(tq->buf_info[0]);
-	tq->buf_info = dma_alloc_coherent(&adapter->pdev->dev, sz,
-					  &tq->buf_info_pa, GFP_KERNEL);
-	if (!tq->buf_info)
+	tq->buf_info = kmalloc_array_node(tq->tx_ring.size, sizeof(tq->buf_info[0]),
+					  GFP_KERNEL | __GFP_ZERO,
+					  dev_to_node(&adapter->pdev->dev));
+	if (!tq->buf_info) {
+		netdev_err(adapter->netdev, "failed to allocate tx buffer info\n");
 		goto err;
+	}
 
 	return 0;
 
@@ -1738,10 +1736,7 @@  static void vmxnet3_rq_destroy(struct vmxnet3_rx_queue *rq,
 	}
 
 	if (rq->buf_info[0]) {
-		size_t sz = sizeof(struct vmxnet3_rx_buf_info) *
-			(rq->rx_ring[0].size + rq->rx_ring[1].size);
-		dma_free_coherent(&adapter->pdev->dev, sz, rq->buf_info[0],
-				  rq->buf_info_pa);
+		kfree(rq->buf_info[0]);
 		rq->buf_info[0] = rq->buf_info[1] = NULL;
 	}
 }
@@ -1883,12 +1878,13 @@  vmxnet3_rq_create(struct vmxnet3_rx_queue *rq, struct vmxnet3_adapter *adapter)
 		goto err;
 	}
 
-	sz = sizeof(struct vmxnet3_rx_buf_info) * (rq->rx_ring[0].size +
-						   rq->rx_ring[1].size);
-	bi = dma_alloc_coherent(&adapter->pdev->dev, sz, &rq->buf_info_pa,
-				GFP_KERNEL);
-	if (!bi)
+	bi = kmalloc_array_node(rq->rx_ring[0].size + rq->rx_ring[1].size,
+				sizeof(rq->buf_info[0][0]), GFP_KERNEL | __GFP_ZERO,
+				dev_to_node(&adapter->pdev->dev));
+	if (!bi) {
+		netdev_err(adapter->netdev, "failed to allocate rx buffer info\n");
 		goto err;
+	}
 
 	rq->buf_info[0] = bi;
 	rq->buf_info[1] = bi + rq->rx_ring[0].size;
@@ -2522,14 +2518,12 @@  vmxnet3_setup_driver_shared(struct vmxnet3_adapter *adapter)
 		tqc->txRingBasePA   = cpu_to_le64(tq->tx_ring.basePA);
 		tqc->dataRingBasePA = cpu_to_le64(tq->data_ring.basePA);
 		tqc->compRingBasePA = cpu_to_le64(tq->comp_ring.basePA);
-		tqc->ddPA           = cpu_to_le64(tq->buf_info_pa);
+		tqc->ddPA           = cpu_to_le64(~0ULL);
 		tqc->txRingSize     = cpu_to_le32(tq->tx_ring.size);
 		tqc->dataRingSize   = cpu_to_le32(tq->data_ring.size);
 		tqc->txDataRingDescSize = cpu_to_le32(tq->txdata_desc_size);
 		tqc->compRingSize   = cpu_to_le32(tq->comp_ring.size);
-		tqc->ddLen          = cpu_to_le32(
-					sizeof(struct vmxnet3_tx_buf_info) *
-					tqc->txRingSize);
+		tqc->ddLen          = cpu_to_le32(0);
 		tqc->intrIdx        = tq->comp_ring.intr_idx;
 	}
 
@@ -2541,14 +2535,11 @@  vmxnet3_setup_driver_shared(struct vmxnet3_adapter *adapter)
 		rqc->rxRingBasePA[0] = cpu_to_le64(rq->rx_ring[0].basePA);
 		rqc->rxRingBasePA[1] = cpu_to_le64(rq->rx_ring[1].basePA);
 		rqc->compRingBasePA  = cpu_to_le64(rq->comp_ring.basePA);
-		rqc->ddPA            = cpu_to_le64(rq->buf_info_pa);
+		rqc->ddPA            = cpu_to_le64(~0ULL);
 		rqc->rxRingSize[0]   = cpu_to_le32(rq->rx_ring[0].size);
 		rqc->rxRingSize[1]   = cpu_to_le32(rq->rx_ring[1].size);
 		rqc->compRingSize    = cpu_to_le32(rq->comp_ring.size);
-		rqc->ddLen           = cpu_to_le32(
-					sizeof(struct vmxnet3_rx_buf_info) *
-					(rqc->rxRingSize[0] +
-					 rqc->rxRingSize[1]));
+		rqc->ddLen           = cpu_to_le32(0);
 		rqc->intrIdx         = rq->comp_ring.intr_idx;
 		if (VMXNET3_VERSION_GE_3(adapter)) {
 			rqc->rxDataRingBasePA =
diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h
index d958b92c9429..e910596b79cf 100644
--- a/drivers/net/vmxnet3/vmxnet3_int.h
+++ b/drivers/net/vmxnet3/vmxnet3_int.h
@@ -240,7 +240,6 @@  struct vmxnet3_tx_queue {
 	spinlock_t                      tx_lock;
 	struct vmxnet3_cmd_ring         tx_ring;
 	struct vmxnet3_tx_buf_info      *buf_info;
-	dma_addr_t                       buf_info_pa;
 	struct vmxnet3_tx_data_ring     data_ring;
 	struct vmxnet3_comp_ring        comp_ring;
 	struct Vmxnet3_TxQueueCtrl      *shared;
@@ -298,7 +297,6 @@  struct vmxnet3_rx_queue {
 	u32 qid2;           /* rqID in RCD for buffer from 2nd ring */
 	u32 dataRingQid;    /* rqID in RCD for buffer from data ring */
 	struct vmxnet3_rx_buf_info     *buf_info[2];
-	dma_addr_t                      buf_info_pa;
 	struct Vmxnet3_RxQueueCtrl            *shared;
 	struct vmxnet3_rq_driver_stats  stats;
 } __attribute__((__aligned__(SMP_CACHE_BYTES)));