Patch "PCI: iproc: Fix NULL pointer dereference for BCMA" has been added to the 4.14-stable tree

This is a note to let you know that I've just added the patch titled

PCI: iproc: Fix NULL pointer dereference for BCMA

to the 4.14-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:
pci-iproc-fix-null-pointer-dereference-for-bcma.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Ray Jui <[email protected]>
Date: Thu, 11 Jan 2018 12:36:16 -0800
Subject: PCI: iproc: Fix NULL pointer dereference for BCMA
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From: Ray Jui <[email protected]>

commit 3b65ca50d24ce33cb92d88840e289135c92b40ed upstream.

With the inbound DMA mapping supported added, the iProc PCIe driver parses DT property "dma-ranges" through call to "of_pci_dma_range_parser_init()". In the case of BCMA, this results in a NULL pointer deference due to a missing of_node.

Fix this by adding a guard in pcie-iproc-platform.c to only enable the inbound DMA mapping logic when DT property "dma-ranges" is present.

---
 drivers/pci/host/pcie-iproc-platform.c |    7 +++++++
 drivers/pci/host/pcie-iproc.c          |    8 +++++---
 drivers/pci/host/pcie-iproc.h          |    2 ++
 3 files changed, 14 insertions(+), 3 deletions(-)

@@ -92,6 +92,13 @@ static int iproc_pcie_pltfm_probe(struct
 		pcie->need_ob_cfg = true;
 	}
 
+	/*
+	 * DT nodes are not used by all platforms that use the iProc PCIe
+	 * core driver. For platforms that require explict inbound mapping
+	 * configuration, "dma-ranges" would have been present in DT
+	 */
+	pcie->need_ib_cfg = of_property_read_bool(np, "dma-ranges");
+
 	/* PHY use is optional */
 	pcie->phy = devm_phy_get(dev, "pcie-phy");
 	if (IS_ERR(pcie->phy)) {

@@ -1396,9 +1396,11 @@ int iproc_pcie_setup(struct iproc_pcie *
 		}
 	}
 
-	ret = iproc_pcie_map_dma_ranges(pcie);
-	if (ret && ret != -ENOENT)
-		goto err_power_off_phy;
+	if (pcie->need_ib_cfg) {
+		ret = iproc_pcie_map_dma_ranges(pcie);
+		if (ret && ret != -ENOENT)
+			goto err_power_off_phy;
+	}
 
 #ifdef CONFIG_ARM
 	pcie->sysdata.private_data = pcie;

@@ -74,6 +74,7 @@ struct iproc_msi;
  * @ob: outbound mapping related parameters
  * @ob_map: outbound mapping related parameters specific to the controller
  *
+ * @need_ib_cfg: indicates SW needs to configure the inbound mapping window
  * @ib: inbound mapping related parameters
  * @ib_map: outbound mapping region related parameters
  *

@@ -101,6 +102,7 @@ struct iproc_pcie {
 	struct iproc_pcie_ob ob;
 	const struct iproc_pcie_ob_map *ob_map;
 
+	bool need_ib_cfg;
 	struct iproc_pcie_ib ib;
 	const struct iproc_pcie_ib_map *ib_map;
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/pci-iproc-fix-null-pointer-dereference-for-bcma.patch