From c88dd2aebf0c85b78918fc4e6c21b29f0f839a71 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Rodr=C3=ADguez=20Barbarin=2C=20Jos=C3=A9=20Javier?= Date: Tue, 11 Apr 2023 10:33:29 +0200 Subject: [PATCH] mcb-lpc: Reallocate memory region to avoid memory overlapping [ Upstream commit 2025b2ca8004c04861903d076c67a73a0ec6dfca ] mcb-lpc requests a fixed-size memory region to parse the chameleon table, however, if the chameleon table is smaller that the allocated region, it could overlap with the IP Cores' memory regions. After parsing the chameleon table, drop/reallocate the memory region with the actual chameleon table size. Co-developed-by: Jorge Sanjuan Garcia Signed-off-by: Jorge Sanjuan Garcia Signed-off-by: Javier Rodriguez Signed-off-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20230411083329.4506-4-jth@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/mcb/mcb-lpc.c | 35 +++++++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/drivers/mcb/mcb-lpc.c b/drivers/mcb/mcb-lpc.c index 506676754538..d513d61f4ba8 100644 --- a/drivers/mcb/mcb-lpc.c +++ b/drivers/mcb/mcb-lpc.c @@ -23,7 +23,7 @@ static int mcb_lpc_probe(struct platform_device *pdev) { struct resource *res; struct priv *priv; - int ret = 0; + int ret = 0, table_size; priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -58,16 +58,43 @@ static int mcb_lpc_probe(struct platform_device *pdev) ret = chameleon_parse_cells(priv->bus, priv->mem->start, priv->base); if (ret < 0) { - mcb_release_bus(priv->bus); - return ret; + goto out_mcb_bus; } - dev_dbg(&pdev->dev, "Found %d cells\n", ret); + table_size = ret; + + if (table_size < CHAM_HEADER_SIZE) { + /* Release the previous resources */ + devm_iounmap(&pdev->dev, priv->base); + devm_release_mem_region(&pdev->dev, priv->mem->start, resource_size(priv->mem)); + + /* Then, allocate it again with the actual chameleon table size */ + res = devm_request_mem_region(&pdev->dev, priv->mem->start, + table_size, + KBUILD_MODNAME); + if (!res) { + dev_err(&pdev->dev, "Failed to request PCI memory\n"); + ret = -EBUSY; + goto out_mcb_bus; + } + + priv->base = devm_ioremap(&pdev->dev, priv->mem->start, table_size); + if (!priv->base) { + dev_err(&pdev->dev, "Cannot ioremap\n"); + ret = -ENOMEM; + goto out_mcb_bus; + } + + platform_set_drvdata(pdev, priv); + } mcb_bus_add_devices(priv->bus); return 0; +out_mcb_bus: + mcb_release_bus(priv->bus); + return ret; } static int mcb_lpc_remove(struct platform_device *pdev)