Re: [PATCH] media: mediatek: vcodec: Fix potential array out-of-bounds in decoder queue_setup

kernel test robot
2023-03-28T13:29:39Z

config: riscv-allmodconfig (https://download.01.org/0day-ci/archive/20230328/202303282152.CXxK3RNH-lkp@intel.com/config)
compiler: riscv64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/caa43627286fb5f3b0b3af7e01e1baeca5c5f9cc
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Wei-Chen/media-mediatek-vcodec-Fix-potential-array-out-of-bounds-in-decoder-queue_setup/20230328-181142
git checkout caa43627286fb5f3b0b3af7e01e1baeca5c5f9cc
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=riscv olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/media/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303282152.CXxK3RNH-lkp@intel.com/

All warnings (new ones prefixed by >>):

drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c: In function 'vb2ops_vdec_queue_setup':
>> drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c:756:20: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
756 | if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
| ^

vim +/else +756 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c

739
740 int vb2ops_vdec_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
741 unsigned int *nplanes, unsigned int sizes[],
742 struct device *alloc_devs[])
743 {
744 struct mtk_vcodec_ctx *ctx = vb2_get_drv_priv(vq);
745 struct mtk_q_data *q_data;
746 unsigned int i;
747
748 q_data = mtk_vdec_get_q_data(ctx, vq->type);
749
750 if (q_data == NULL) {
751 mtk_v4l2_err("vq->type=%d err\n", vq->type);
752 return -EINVAL;
753 }
754
755 if (*nplanes) {
> 756 if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
757 if (*nplanes != q_data->fmt->num_planes)
758 return -EINVAL;
759 else
760 if (*nplanes != 1)
761 return -EINVAL;
762
763 for (i = 0; i < *nplanes; i++) {
764 if (sizes[i] < q_data->sizeimage[i])
765 return -EINVAL;
766 }
767 } else {
768 if (vq->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
769 *nplanes = q_data->fmt->num_planes;
770 else
771 *nplanes = 1;
772
773 for (i = 0; i < *nplanes; i++)
774 sizes[i] = q_data->sizeimage[i];
775 }
776
777 mtk_v4l2_debug(1,
778 "[%d]\t type = %d, get %d plane(s), %d buffer(s) of size 0x%x 0x%x ",
779 ctx->id, vq->type, *nplanes, *nbuffers,
780 sizes[0], sizes[1]);
781
782 return 0;
783 }
784