media: intel-ipu3: cio2: fix a crash with out-of-bounds access

When dmabuf is used for BLOB type frame, the frame
buffers allocated by gralloc will hold more pages
than the valid frame data due to height alignment.

In this case, the page numbers in sg list could exceed the
FBPT upper limit value - max_lops(8)*1024 to cause crash.

Limit the LOP access to the valid data length
to avoid FBPT sub-entries overflow.

Signed-off-by: Yong Zhi <yong.zhi@intel.com>
Signed-off-by: Cao Bing Bu <bingbu.cao@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Yong Zhi 2018-01-03 21:57:16 -05:00 committed by Mauro Carvalho Chehab
parent 883dd4c1b8
commit c7cbef1fdb

View File

@ -838,8 +838,9 @@ static int cio2_vb2_buf_init(struct vb2_buffer *vb)
container_of(vb, struct cio2_buffer, vbb.vb2_buf);
static const unsigned int entries_per_page =
CIO2_PAGE_SIZE / sizeof(u32);
unsigned int pages = DIV_ROUND_UP(vb->planes[0].length, CIO2_PAGE_SIZE);
unsigned int lops = DIV_ROUND_UP(pages + 1, entries_per_page);
unsigned int pages = DIV_ROUND_UP(vb->planes[0].length,
CIO2_PAGE_SIZE) + 1;
unsigned int lops = DIV_ROUND_UP(pages, entries_per_page);
struct sg_table *sg;
struct sg_page_iter sg_iter;
int i, j;
@ -869,6 +870,8 @@ static int cio2_vb2_buf_init(struct vb2_buffer *vb)
i = j = 0;
for_each_sg_page(sg->sgl, &sg_iter, sg->nents, 0) {
if (!pages--)
break;
b->lop[i][j] = sg_page_iter_dma_address(&sg_iter) >> PAGE_SHIFT;
j++;
if (j == entries_per_page) {