diff options
| author | Jason-JH.Lin <jason-jh.lin@mediatek.com> | 2023-09-07 17:14:25 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-03-28 21:59:02 +0100 |
| commit | a12bd675100531f9fb4508fd4430dd1632325a0e (patch) | |
| tree | 8379a39cb6168544079d5ec5abee5f6829d5b759 | |
| parent | 2d4a7a091fd6bee5dc22445ee0adca3eca3c3291 (diff) | |
| download | linux-a12bd675100531f9fb4508fd4430dd1632325a0e.tar.gz linux-a12bd675100531f9fb4508fd4430dd1632325a0e.tar.bz2 linux-a12bd675100531f9fb4508fd4430dd1632325a0e.zip | |
drm/mediatek: Fix coverity issue with unintentional integer overflow
commit b0b0d811eac6b4c52cb9ad632fa6384cf48869e7 upstream.
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-jason-jh.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
[ For certain code segments with coverity issue do not exist in
function mtk_plane_update_new_state(), those not present in v6.1 are
not back ported. ]
Signed-off-by: Bin Lan <bin.lan.cn@windriver.com>
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/gpu/drm/mediatek/mtk_drm_gem.c | 9 | ||||
| -rw-r--r-- | drivers/gpu/drm/mediatek/mtk_drm_plane.c | 13 |
2 files changed, 19 insertions, 3 deletions
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c index 21e584038581..336a6ee792c6 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c @@ -119,7 +119,14 @@ 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 30d361671aa9..fb062e52eb12 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c @@ -120,6 +120,7 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, struct mtk_drm_gem_obj *mtk_gem; unsigned int pitch, format; dma_addr_t addr; + int offset; gem = fb->obj[0]; mtk_gem = to_mtk_gem_obj(gem); @@ -127,8 +128,16 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, pitch = fb->pitches[0]; format = fb->format->format; - 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; + mtk_plane_state->pending.enable = true; mtk_plane_state->pending.pitch = pitch; |