[PATCH AUTOSEL 6.0 17/34] media: atomisp: Ensure that USERPTR pointers are page aligned

Sasha Levin
2022-11-01T11:29:25Z

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit 6e6c4ae0f0ba295dbf6cbd48d93bec169d6ce431 ]

The atomisp code needs USERPTR pointers to be page aligned,
otherwise bad things (scribbling over other parts of the
process' RAM) happen.

Add a check to ensure this and exit VIDIOC_QBUF calls with
unaligned pointers with -EINVAL.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/staging/media/atomisp/pci/atomisp_ioctl.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
index 459645c2e2a7..4de01aa28fe5 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
@@ -1338,6 +1338,12 @@ static int atomisp_qbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
* address and reprograme out page table properly
*/
if (buf->memory == V4L2_MEMORY_USERPTR) {
+ if (offset_in_page(buf->m.userptr)) {
+ dev_err(isp->dev, "Error userptr is not page aligned.\n");
+ ret = -EINVAL;
+ goto error;
+ }
+
vb = pipe->capq.bufs[buf->index];
vm_mem = vb->priv;
if (!vm_mem) {
--
2.35.1