From bce7698e2e6565bb765bd0522337f29f5f312624 Mon Sep 17 00:00:00 2001 From: Haojie Li Date: Tue, 25 Aug 2026 18:08:45 +0800 Subject: drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform device platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Cc: stable@vger.kernel.org Signed-off-by: Haojie Li Reviewed-by: CK Hu Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/ Signed-off-by: Chun-Kuang Hu --- lib/iommu-helper.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 lib/iommu-helper.c (limited to 'lib/iommu-helper.c') diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c new file mode 100644 index 000000000..92a9f243c --- /dev/null +++ b/lib/iommu-helper.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * IOMMU helper functions for the free area management + */ + +#include +#include + +unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, + unsigned long start, unsigned int nr, + unsigned long shift, unsigned long boundary_size, + unsigned long align_mask) +{ + unsigned long index; + + /* We don't want the last of the limit */ + size -= 1; +again: + index = bitmap_find_next_zero_area(map, size, start, nr, align_mask); + if (index < size) { + if (iommu_is_span_boundary(index, nr, shift, boundary_size)) { + start = ALIGN(shift + index, boundary_size) - shift; + goto again; + } + bitmap_set(map, index, nr); + return index; + } + return -1; +} -- cgit v1.3.1