From: Guenter Roeck groeck@chromium.org
[ Upstream commit ef693a8440926884bfd9cc3d6d36f65719513350 ]
Fix the smatch warnings: drivers/iommu/mtk_iommu.c:878 mtk_iommu_mm_dts_parse() error: uninitialized symbol 'larbnode'.
If someone abuse the dtsi node(Don't follow the definition of dt-binding), for example "mediatek,larbs" is provided as boolean property, "larb_nr" will be zero and cause abnormal.
To fix this problem and improve the code safety, add some checking for the invalid input from dtsi, e.g. checking the larb_nr/larbid valid range, and avoid "mediatek,larb-id" property conflicts in the smi-larb nodes.
Fixes: d2e9a1102cfc ("iommu/mediatek: Contain MM IOMMU flow with the MM TYPE") Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Guenter Roeck groeck@chromium.org Signed-off-by: Yong Wu yong.wu@mediatek.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Matthias Brugger matthias.bgg@gmail.com Link: https://lore.kernel.org/r/20221018024258.19073-5-yong.wu@mediatek.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/mtk_iommu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 39f4c79e9c71..213fc8f5b6c1 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -1048,6 +1048,8 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m larb_nr = of_count_phandle_with_args(dev->of_node, "mediatek,larbs", NULL); if (larb_nr < 0) return larb_nr; + if (larb_nr == 0 || larb_nr > MTK_LARB_NR_MAX) + return -EINVAL;
for (i = 0; i < larb_nr; i++) { u32 id; @@ -1066,6 +1068,11 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id); if (ret)/* The id is consecutive if there is no this property */ id = i; + if (id >= MTK_LARB_NR_MAX) { + of_node_put(larbnode); + ret = -EINVAL; + goto err_larbdev_put; + }
plarbdev = of_find_device_by_node(larbnode); of_node_put(larbnode); @@ -1073,6 +1080,11 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m ret = -ENODEV; goto err_larbdev_put; } + if (data->larb_imu[id].dev) { + platform_device_put(plarbdev); + ret = -EEXIST; + goto err_larbdev_put; + } data->larb_imu[id].dev = &plarbdev->dev;
if (!plarbdev->dev.driver) {