6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jason-JH.Lin jason-jh.lin@mediatek.com
[ Upstream commit b0b0d811eac6b4c52cb9ad632fa6384cf48869e7 ]
1. Instead of multiplying 2 variable of different types. Change to assign a value of one variable and then multiply the other variable.
2. Add a int variable for multiplier calculation instead of calculating different types multiplier with dma_addr_t variable directly.
Fixes: 1a64a7aff8da ("drm/mediatek: Fix cursor plane no update") Signed-off-by: Jason-JH.Lin jason-jh.lin@mediatek.com Reviewed-by: Alexandre Mergnat amergnat@baylibre.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Link: https://patchwork.kernel.org/project/dri-devel/patch/20230907091425.9526-1-j... Signed-off-by: Chun-Kuang Hu chunkuang.hu@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/mediatek/mtk_drm_gem.c | 9 +++++- drivers/gpu/drm/mediatek/mtk_drm_plane.c | 39 ++++++++++++++++++------ 2 files changed, 38 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c index 0e0a41b2f57f0..4f2e3feabc0f8 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c @@ -121,7 +121,14 @@ int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, int ret;
args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8); - args->size = args->pitch * args->height; + + /* + * Multiply 2 variables of different types, + * for example: args->size = args->spacing * args->height; + * may cause coverity issue with unintentional overflow. + */ + args->size = args->pitch; + args->size *= args->height;
mtk_gem = mtk_drm_gem_create(dev, args->size, false); if (IS_ERR(mtk_gem)) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c index db2f70ae060d6..5acb03b7c6fe5 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c @@ -141,6 +141,7 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, dma_addr_t addr; dma_addr_t hdr_addr = 0; unsigned int hdr_pitch = 0; + int offset;
gem = fb->obj[0]; mtk_gem = to_mtk_gem_obj(gem); @@ -150,8 +151,15 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, modifier = fb->modifier;
if (modifier == DRM_FORMAT_MOD_LINEAR) { - addr += (new_state->src.x1 >> 16) * fb->format->cpp[0]; - addr += (new_state->src.y1 >> 16) * pitch; + /* + * Using dma_addr_t variable to calculate with multiplier of different types, + * for example: addr += (new_state->src.x1 >> 16) * fb->format->cpp[0]; + * may cause coverity issue with unintentional overflow. + */ + offset = (new_state->src.x1 >> 16) * fb->format->cpp[0]; + addr += offset; + offset = (new_state->src.y1 >> 16) * pitch; + addr += offset; } else { int width_in_blocks = ALIGN(fb->width, AFBC_DATA_BLOCK_WIDTH) / AFBC_DATA_BLOCK_WIDTH; @@ -159,21 +167,34 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, / AFBC_DATA_BLOCK_HEIGHT; int x_offset_in_blocks = (new_state->src.x1 >> 16) / AFBC_DATA_BLOCK_WIDTH; int y_offset_in_blocks = (new_state->src.y1 >> 16) / AFBC_DATA_BLOCK_HEIGHT; - int hdr_size; + int hdr_size, hdr_offset;
hdr_pitch = width_in_blocks * AFBC_HEADER_BLOCK_SIZE; pitch = width_in_blocks * AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT * fb->format->cpp[0];
hdr_size = ALIGN(hdr_pitch * height_in_blocks, AFBC_HEADER_ALIGNMENT); + hdr_offset = hdr_pitch * y_offset_in_blocks + + AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks; + + /* + * Using dma_addr_t variable to calculate with multiplier of different types, + * for example: addr += hdr_pitch * y_offset_in_blocks; + * may cause coverity issue with unintentional overflow. + */ + hdr_addr = addr + hdr_offset;
- hdr_addr = addr + hdr_pitch * y_offset_in_blocks + - AFBC_HEADER_BLOCK_SIZE * x_offset_in_blocks; /* The data plane is offset by 1 additional block. */ - addr = addr + hdr_size + - pitch * y_offset_in_blocks + - AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT * - fb->format->cpp[0] * (x_offset_in_blocks + 1); + offset = pitch * y_offset_in_blocks + + AFBC_DATA_BLOCK_WIDTH * AFBC_DATA_BLOCK_HEIGHT * + fb->format->cpp[0] * (x_offset_in_blocks + 1); + + /* + * Using dma_addr_t variable to calculate with multiplier of different types, + * for example: addr += pitch * y_offset_in_blocks; + * may cause coverity issue with unintentional overflow. + */ + addr = addr + hdr_size + offset; }
mtk_plane_state->pending.enable = true;