A large cs->count from userspace may overflow the allocation size,
leading to memory corruption. try_set_ext_ctrls() can be reached
from subdev_do_ioctl() or __video_do_ioctl().
Use kmalloc_array() to avoid the overflow.
Signed-off-by: Xi Wang <xi.wang@xxxxxxxxx>
---
drivers/media/video/v4l2-ctrls.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c
index f355fd5..6f38a5d 100644
--- a/drivers/media/video/v4l2-ctrls.c
+++ b/drivers/media/video/v4l2-ctrls.c
@@ -2219,7 +2219,8 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
return class_check(hdl, cs->ctrl_class);
if (cs->count > ARRAY_SIZE(helper)) {
- helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
+ helpers = kmalloc_array(cs->count, sizeof(helper[0]),
+ GFP_KERNEL);
if (!helpers)
return -ENOMEM;
}
--
1.7.5.4
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