[PATCH v3 23/23] drm/qxl: add overflow checks to qxl_mode_dumb_create()

From: Gerd Hoffmann
Date: Fri Jan 18 2019 - 07:20:57 EST


Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
drivers/gpu/drm/qxl/qxl_dumb.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_dumb.c b/drivers/gpu/drm/qxl/qxl_dumb.c
index 272d19b677..bed6d06ee4 100644
--- a/drivers/gpu/drm/qxl/qxl_dumb.c
+++ b/drivers/gpu/drm/qxl/qxl_dumb.c
@@ -37,11 +37,13 @@ int qxl_mode_dumb_create(struct drm_file *file_priv,
uint32_t handle;
int r;
struct qxl_surface surf;
- uint32_t pitch, format;
+ uint32_t pitch, size, format;

- pitch = args->width * ((args->bpp + 1) / 8);
- args->size = pitch * args->height;
- args->size = ALIGN(args->size, PAGE_SIZE);
+ if (check_mul_overflow(args->width, ((args->bpp + 1) / 8), &pitch))
+ return -EINVAL;
+ if (check_mul_overflow(pitch, args->height, &size))
+ return -EINVAL;
+ args->size = ALIGN(size, PAGE_SIZE);

switch (args->bpp) {
case 16:
--
2.9.3