From: Guenter Roeck <gro...@chromium.org> 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 <l...@intel.com> Reported-by: Dan Carpenter <dan.carpen...@oracle.com> Signed-off-by: Guenter Roeck <gro...@chromium.org> Signed-off-by: Yong Wu <yong...@mediatek.com> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delre...@collabora.com> --- drivers/iommu/mtk_iommu.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index ab24078938bf..a869d4aee7b3 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -1052,6 +1052,8 @@ 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; @@ -1068,6 +1070,10 @@ 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) { + ret = -EINVAL; + goto err_larbnode_put; + } plarbdev = of_find_device_by_node(larbnode); if (!plarbdev) { @@ -1078,6 +1084,11 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m ret = -EPROBE_DEFER; goto err_larbnode_put; } + + if (data->larb_imu[id].dev) { + ret = -EEXIST; + goto err_larbnode_put; + } data->larb_imu[id].dev = &plarbdev->dev; component_match_add_release(dev, match, component_release_of, -- 2.18.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu