vb2_ioctl_remove_bufs() call manipulates queue internal buffer list, potentially overwriting some pointers used by the legacy fileio access mode. Add a vb2_verify_memory_type() check symmetrical to vb2_ioctl_create_bufs() to forbid that ioctl when fileio is active to protect internal queue state between subsequent read/write calls.
CC: stable@vger.kernel.org Fixes: a3293a85381e ("media: v4l2: Add REMOVE_BUFS ioctl") Reported-by: Shuangpeng BaiSJB7183@psu.edu Suggested-by: Benjamin Gaignard benjamin.gaignard@collabora.com Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/media/common/videobuf2/videobuf2-v4l2.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index d911021c1bb0..a8a5b42a42d0 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -1000,13 +1000,15 @@ int vb2_ioctl_remove_bufs(struct file *file, void *priv, struct v4l2_remove_buffers *d) { struct video_device *vdev = video_devdata(file); - - if (vdev->queue->type != d->type) - return -EINVAL; + int res;
if (d->count == 0) return 0;
+ res = vb2_verify_memory_type(vdev->queue, vdev->queue->memory, d->type); + if (res) + return res; + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY;